FACTSHEET ABOUT SOFT TISSUE SARCOMAS
Definition of soft tissue sarcomas
- It describes a group of malignant tumours that originate in “soft tissues”. Soft tissues include muscles, tendons, fat, blood and lymph vessels, nerves and joint linings (synovial tissue*).
- As soft tissues are found everywhere in the body, soft tissue sarcomas may arise in any part of the
- Unfortunately, sarcomas* can be asymptomatic for a long time and the symptoms will depend on the part of the body which is Sarcomas can be suspected when a lump appears on a leg, an arm or the trunk.
- Radiological examinations* are mandatory to determine the extent of a soft tissue sarcoma and to establish the presence or absence of distant metastasis*.
- A sample of the tumour (biopsy*) must be obtained for analysis in the laboratory to confirm the diagnosis and get more details about the type of sarcoma*.
- Localised sarcomas are confined to the primary site and have not spread to nearby tissues or to other areas of the
- Removal of the tumour by surgery is the standard treatment
- Radiotherapy* and chemotherapy*, either alone or in combination after surgery, can sometimes be used to increase the chance of definitive cure or reduce the risk that the tumour comes
- Radiotherapy* can be used before surgery to shrink the size of the tumour and allow it to be removed completely
- Advanced sarcomas* have spread from where they started to other parts of the body. This is known as metastatic or advanced
- The main treatment approach is the use of chemotherapy* and molecularly targeted therapy*. The choice of the drugs will mainly depend on the clinical conditions of the patient and on the type of sarcomas*.
- Radiotherapy* either during or after chemotherapy* could be used to relieve symptoms and control metastases*.
- Surgery may be used to relieve symptoms or to cure the cancer in some specific
- Follow−up appointments include physical examination, blood tests and radiological examination; they will be done for several
The optimal time schedule for follow−up for soft tissue sarcomas is unknown and depends on the location, the size and the aggressiveness (grade) of the tumour. Follow−up after treatment for high or intermediate grade soft tissue sarcoma is more intensive than for low grade sarcoma*.
What is Sarcoma?
A rare kind of cancer that grows in connective tissues – cells that connect or support other kinds of tissue in your body, its also termed as Soft-tissue Sarcoma. As soft tissues are found everywhere in the body, soft tissue sarcomas may rise in any part of the body. Soft tissues include muscles, tendons, fat, blood and lymph vessels and joint linings(Synovial tissue). Soft tissue Sarcoma’s are a diverse group of malignant tumours that originate when abnormal cells grow out of control in Soft tissues and connective tissues. The type of Sarcoma depends on the kinds of cells it arises from. Connective tissues include all tissues that support, connect or separate different tissues in the body. Therefore it can be found in the structure of organs in the body. Soft tissue sarcomas, therefore can grow almost anywhere, but are most common in arms and legs followed by trunk and abdomen, head and neck.
What causes Soft tissue Sarcomas?
It is not yet clear why soft tissue sarcomas occur. But Scientists have found several risk factors that can make a person more likely to develop these cancers. And research has shown that some of these risk factors affect the DNA of cells in soft tissues. Researchers have made great progress in understanding how certain changes in DNA can cause normal cells to become cancerous. Our DNA carries the instructions for nearly everything our cells do. Several family cancer syndromes have been found in which inherited DNA mutations cause a very high risk of developing breast, colon, kidney, eye or other cancers. In some of these, there is also an increased risk of developing soft tissue sarcomas. Thus according to American Cancer Society scientists have found a few risk factors that make a person more likely to develop Soft tissue Sarcoma’s
- Certain Family Cancer Syndromes
- A damaged lymph system
- Exposure to certain chemicals
Injury and lifestyle factors such as smoking, diet and exercise are NOT linked to the risk of Soft tissue Sarcoma.
Symptoms and signs
Generally Sarcomas can start in any part of the body. The types of symptoms that people have from Sarcoma depend where it starts. People with Sarcoma may experience the following symptoms or signs. Sometimes, people with sarcoma do not have any of these changes. Or, the cause of a symptom may be a different medical condition that is not cancer. Soft Tissue Sarcomas rarely causes symptoms in early stages. The first sign of a sarcoma in an arm or leg, or torso maybe a painless lump or swelling. As noted in statistics, most lumps are not cancer. Lipomas have often been there for many years and rarely change in size. In the uterus, benign tumours called fibroids, or leimyomas, far outnumber sarcomas. However, its important to talk to your doctor about any lumps that are larger than 2 inches(5 cm),grow larger, or a painful, regardless of their location. People with sarcoma that starts in the abdomen may not have any symptoms, or they may have pain or a sense of fullness. Sarcomas that arise in other parts of body may cause other symptoms or signs. For example, Sarcomas that arise in the uterus can cause uterine bleeding or an increase in the size of the uterus. Tumours that start in heart or lungs may cause breathing problems or pain in the chest.
How are Soft tissue Sarcomas Diagnosed?
Sarcomas often do not caused symptoms for a long time, until they become quite large and press on an organ, a nerve or a muscle. They may arise in any part of the body and symptoms will depend on the part of the body that is affected. The main circumstances is when a lump appears on the leg, arm or trunk. They may also be found during an investigation of other symptoms or during a routine operation.
The diagnosis of Sarcoma is based on following examinations:
- Medical History and Clinical Examination: Your doctor will begin by taking your complete medical history, asking when the symptoms began and how they have changed over time and check for risk factors. Your doctor then perform a complete physical examination, including the area where is the lump and or pain. If the sarcoma is in any part of arm or leg, the most symptom is an uncomfortable swelling. Occasionally, this swelling may be painful or tender, but it may also be painless. If the sarcoma is in the central part of the body( the trunk),the symptoms depend on which organ is affected. For example, a sarcoma in lung may cause breathlessness and cough; a lump in abdomen could cause abdominal pain, vomiting and constipation; a sarcoma affecting the womb could cause uterine bleeding and pain in the lower part of the abdomen, occurring outside of menstrual periods.
- Blood Test: A blood sample is performed to check your general health status, and to explore the function of liver, kidney and blood cells.
- Radiological Examination: A wide ranging of imaging techniques is used to look inside the body to determine the extent of a soft tissue sarcoma and establish the presence or absence of distant metastatic disease.
- Chest X- Ray : A plain chest X-ray could be done to determine whether the sarcoma has spread to the lungs, as this is one of the most common sites it may spread to.
- Ultrasonography : A type of examination that uses sound waves and their echoes to create images within the body. There are different kinds of ultrasound scans depending on which part of the body is being examined and why. An external ultrasound may be used to examine the liver, kidneys, and other organs in the abdomen and pelvis, or heart function. An ultrasound Scan( EUS) uses a tube-like instrument called endoscope with an ultrasound scanner attached; it uses sound waves to produce of abdominal organs.
- CT Scan : a computerized Tomography scan is an X-Ray technique that produces detailed pictures of the inside of the body. You may be asked to drink a liquid called oral contrast and you may also receive an intravenous contrast dye to help the organs or tissues show up more clearly.
- PET Scan : Position Emission Tomography is mainly used to find out if the Sarcoma has spread to other parts of the body. It uses a substance that contains glucose, which is injected into the patient. This radiolabeled glucose-based substance is absorbed by cancerous cells which are less able to eliminate it than normal tissue so that it remains “trapped” in cancerous tissues. PET scans can also be used to examine the effect of the treatment on tumours.
- MRI: Magnetic Resonance Imaging uses magnetic fields and radio waves to create a series of detailed pictures of the tissue of the body. MRI is able to show more clearly soft tissues than other types of Scan. It is often used for tumours of the limbs.
- Bone Scintigraphy: a Type of scan using radiolabeled substance to find out whether the sarcoma has spread to the bones. The radiolabeled substance travels to areas of bone changes, which appear brighter and indicates possible spread of the tumour.
- Histapathological Examinations: Hispathologic exam is made on biopsy or piece of tissue after excision of the whole tumour by surgery. Only the hispathologic assessment of the tumour will disclose whether the tumour is a soft tissue Sarcoma, and type of Sarcoma. It will also provide the “malignancy grade” i.e a score of the aggressiveness of the cells making the tumor.
A biopsy takes a sample of the tumour, which will be examined under a microscope to look for cancer cells. Different types of biopsies may be used: Core needle biopsy, excisional biopsy and open biopsy.
- Core needle Biopsy: a sample of cells or part of lump is removed using a needle. Before the biopsy is taken, a local anaesthetic is injected to numb the area and several samples may be taken. If the lump is deep within the body the doctor may use an ultrasound or a CT Scan to guide the needle into right place.
- Incisional / Excisional Biopsy: Under anesthesia, a surgical knife is used to remove a tissue sample from the lump(“incisional”), or the entire tumour(“excisional”).This is the most practical option for rather small sarcomas near the surface of the body(<5cm superficial lesions)
Open Biopsy : a surgical knife is used to open the area and remove a tissue sample from the lump or the entire tumour; it may be done under a local or general anaesthesia, depending on the position and depth of the tumour.
Soft Tissue Sarcoma: Stages and Grades
Staging is a way of describing where the cancer is located, if or where it has spread, and whether it is affecting other parts of the body. Doctors use diagnostic tests to find out the cancer's stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient's prognosis, which is the chance of recovery. There are different stage descriptions for different types of cancer. There are several systems used to describe the stage of sarcoma. These systems are somewhat different from each other, but all use an overall stage to help predict a person’s prognosis.
TNM Staging System
One tool that doctors use to describe the stage is the TNM system. Doctors use the results from diagnostic tests and scans to answer these questions:
- Tumor (T):How large is the primary tumor? Where is it located?
- Node (N):Has the tumor spread to the lymph nodes? If so, where and how many?
- Metastasis (M):Has the cancer metastasized to other parts of the body? If so, where and how much?
The results are combined to determine the stage of cancer for each person. There are 4 stages: stages I through IV (1 through 4). The stage provides a common way of describing the cancer, so doctors can work together to plan the best treatments.
Here are more details on each part of the TNM system for sarcoma:
Using the TNM system, the "T" plus a number (0 to 2) and letter (a or b) is used to describe the size and location of the tumor.
The tumor (T) is further described by its depth. The tumor depth is described as either “superficial” or “deep.” The tumor depth is described as “superficial” when the tumor is above the body's superficial tissue. It is described as “deep” when the tumor is beneath the body's superficial tissue or has grown into the deep tissue. Specific tumor stage information is listed below.
TX: The primary tumor cannot be evaluated.
T0 (T plus zero): There is no evidence of a primary tumor.
T1: The size of the tumor is 5 centimeters (cm) or smaller.
- T1a:The tumor is superficial.
- T1b:The tumor is deep.
T2: The size of the tumor is larger than 5 cm.
- T2a:The tumor is superficial.
T2b: The tumor is deep.
The "N" in the TNM staging system stands for lymph nodes. These tiny, bean-shaped organs help fight infection. Lymph nodes near where the cancer started are called regional lymph nodes. Lymph nodes in other parts of the body are called distant lymph nodes. Soft-tissue sarcoma usually does not spread to lymph nodes.
NX: Regional lymph nodes cannot be evaluated.
N0 (N plus zero): The cancer has not spread to regional lymph nodes.
N1: The cancer has spread to regional lymph nodes.
The "M" in the TNM system indicates whether the cancer has spread to other parts of the body, called distant metastasis.
M0 (M plus zero): The cancer has not metastasized.
M1: There is metastasis to another part of the body.
Doctors also describe this type of cancer by its grade (G), which describes how much cancer cells look like healthy cells when viewed under a microscope.
The doctor compares the cancerous tissue with healthy tissue. Healthy tissue usually contains many different types of cells grouped together. If the cancer looks similar to healthy tissue and contains different cell groupings, it is called “differentiated” or a “low-grade tumor.” If the cancerous tissue looks very different from healthy tissue, it is called “poorly differentiated” or a “high-grade tumor.” The cancer’s grade may help the doctor predict how quickly the cancer will spread. In general, the lower the tumor’s grade, the better the prognosis.
There are 4 grades for sarcoma: GX (the grade cannot be evaluated), G1, G2, and G3. The grades are determined based on the factors below:
- How different the cancer cells are from normal tissue cells
- How many tumor cells are dividing
- How much of the tumor has cells that are dying
The lower the combined score for these 3 factors, the lower the grade. A lower grade means that the tumour is less aggressive and that a patient’s prognosis is better. This is the recommended grading system, but other systems may also be used. For instance, some doctors grade sarcomas as either “low grade” or “high grade,” particularly if the tumour has been treated before surgery.
Cancer Stage Grouping
Doctors assign the stage of the cancer by combining the T, N, M, and G classifications. For sarcoma, stages I and II are described with subgroups according to the tumor's depth.
Stage IA: The tumor is 5 cm or less in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body (T1a or T1b, N0, M0, GX or G1).
Stage IB: The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body (T2a or T2b, N0, M0, GX or G1).
Stage IIA: The tumor is 5 cm or less in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IA (T1a or T1b, N0, M0, G2 or G3).
Stage IIB: The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IB (T2a or T2b, N0, M0, G2).
Stage III: This stage can be described by either of the following:
- The tumor is more than 5 cm in size, and it is either superficial or deep. It has not spread to lymph nodes or to other parts of the body. The grade is higher than the grade for stage IIB (T2a or T2b, N0, M0, G3).
- The tumor is any size, either superficial or deep, or any grade. It has spread to the regional lymph nodes but not to other parts of the body (any T, N1, M0, any G).
Stage IV: The tumor is any size, either superficial or deep, any grade, and may or may not have spread to the regional lymph nodes. It has spread to other parts of the body (any T, any N, M1, and any G).
This staging system applies to most types of STS, except Kaposi sarcoma; GIST; infantile fibrosarcoma; sarcomas that begin in the central nervous system, which includes the brain or the lining around the brain and spinal cord; and sarcomas that begin in an organ or a hollow organ, such as the bowel or urinary tract.
Recurrent: Recurrent cancer is cancer that comes back after treatment. If the cancer does return, there will be another round of tests to learn about the extent of the recurrence.
Types of Soft Tissue Sarcoma
Soft tissue sarcoma is not a common cancer. Some types are more common in children, and others are more common in adults. Certain types of soft tissue sarcoma occur more often in a specific age group. Some types occur in certain parts of the body:
- Over 50% of soft tissue sarcomas begin in the limbs. They develop in lower limbs more often than upper limbs and occur most often in the thigh.
- About 15% of soft tissue sarcomas start inside the abdomen or chest.
- About 15% of soft tissue sarcomas start in the retroperitoneum (back of the abdominal cavity).
About 5-10% occur in the head or neck.
Fat Tissue Tumour
Liposarcoma is a cancerous soft tissue tumour that starts in the fatty (adipose) tissue of the body.
Fibrous Tissue Tumour
Several different cancerous tumours can develop in fibrous tissues that join together the inner structures of the body. Some soft tissue sarcomas of the fibrous tissue include:
- malignant fibrous histiocytomas
- dermatofibrosarcoma protuberans
Muscle Tissue Tumour
Soft tissue sarcomas occur most often in smooth (involuntary) muscle. They may also develop in skeletal (voluntary) muscle.
Leiomyosarcoma develops in smooth muscle.
Rhabdomyosarcoma develops in skeletal muscle.
Blood and Lymph Tumour
Cancerous tumours of the blood and lymphatic vessels may also be called malignant vascular tumours. These include:
- Kaposi sarcoma
Gastrointestinal stromal tumours (GISTS)
Gastrointestinal stromal tumours (GISTS) are a type of soft tissue sarcoma that can develop anywhere along the gastrointestinal tract.
Gastrointestinal (GI) stromal tumours, or GISTs, start in interstitial cells of Cajal (ICCs). ICCs are specialized cells in the GI tract. They have characteristics of both smooth muscle cells and nerve cells. They receive signals from the brain to make muscles in the stomach, small intestine and large intestine tighten (contract) and relax (expand). The tightening and relaxing of these muscles is called peristalsis. This process moves food and liquid through the digestive system.
GISTs are a common type of soft tissue sarcoma. A GIST can occur anywhere in the GI tract, but they develop most often in the stomach. The small intestine is the second most common location. GISTs can also develop in the esophagus, colon, rectum, omentum and mesentery. The omentum is a fatty fold in the peritoneum (the membrane that lines the walls of the abdomen and pelvis) that covers and supports organs and blood vessels in the abdomen. The mesentery is fatty tissue that contains the blood vessels to the bowel as well as lymph nodes.
GISTs can develop at any age, but they usually occur in people over 50 years of age. Most GISTs have a mutation in the KIT, or c-Kit, gene. This mutation causes the body to make too much of the KIT protein. The second most common mutation in GISTs is in the platelet-derived growth factor receptor alpha (PDGFRA) gene. This mutation causes the body to make too much PDGFRA protein. Both the KIT and PDGFRA proteins are enzymes called tyrosine kinases, which signal cells to grow and can trigger some GISTs to grow in an uncontrolled way.
Almost all GISTs occur sporadically. This means there is no clear reason why they develop. In a small number of people, GIST develops due to a hereditary syndrome. These syndromes include:
- familial GIST syndrome
- neurofibromatosis type 1 (von Recklinghausen disease)
- Carney-Stratakis syndrome
- Carney’s triad
These syndromes are unavoidable, so there is no way for people who have them to lower their risk of developing GISTs.
GISTs usually don’t cause symptoms in the early stages. Symptoms tend to occur only when the tumour has grown large enough to cause problems. The symptoms of GISTs depend on if they develop in the stomach or small intestine. Signs and symptoms may include:
- loss of appetite
- weight loss
- a lump in the abdomen
- abdominal pain or discomfort
- bleeding from the GI tract, such as vomiting blood or blood in the stool
- fatigue due to anemia caused by bleeding in the GI tract
GISTs are often discovered when you don’t have any symptoms. They may be found when you have an imaging test for another reason.
Diagnosing GISTs usually begins with a visit to your family doctor. Your doctor will ask you about any symptoms you have and will do a physical exam. Based on this information, your doctor may refer you to a specialist or order tests to check for GISTs or other health problems. This may include the following:
- complete blood count (CBC)
- blood chemistry tests
- fecal occult blood test (FOBT)
- computed tomography (CT) scan or magnetic resonance imaging (MRI) of the abdomen and pelvis
- ultrasound of the abdomen
- gastroscopy or upper GI endoscopy
- endoscopic ultrasound
Your doctor may do a biopsy during an endoscopy. The sample taken during endoscopy may be too small to give a definite diagnosis. Ideally, a tissue biopsy should be taken to confirm the diagnosis of a GIST before a treatment plan is started. This biopsy is usually done at a clinic by doctors with experience treating GISTs. A sarcoma specialist will plan the biopsy, which may be done by a specialised radiologist.
Types of GISTS
GISTs may be non-cancerous, or benign. This means that they usually do not spread, or metastasize, to other parts of the body. They are not usually life-threatening. Smaller tumours that are less than 2 cm in diameter are usually non-cancerous.
GISTs can also be cancerous, or malignant. Cancerous tumours can spread to other parts of the body. GISTs that are larger than 2 cm are more likely to be cancerous. In general, smaller tumours have a better prognosis than larger tumours. Other factors that are important in predicting the behaviour of GISTs are tumour location and grade.
Grade is the most important factor in planning treatment and predicting outcome for GISTs. To find the grade of a GIST, the pathologist looks at a tissue sample from the tumour under a microscope. The grade that the pathologist gives is based on the mitotic rate, which is how fast the cancer cells are growing and dividing. The grade is described as being either low or high. GISTs with a low mitotic rate have a better prognosis.
Knowing the grade gives your healthcare team an idea of how quickly the cancer may be growing and how likely it is to spread. This helps them plan your treatment. The grade can also help the healthcare team predict how you might respond to treatment.
|Grade||Mitotic rate||Number of mitoses per 50 high-power fields (HPF)|
|low||Low||less than 5|
|high||High||more than 5|
Stages of GISTS
Staging describes or classifies a cancer based on how much cancer there is in the body and where it is when first diagnosed. This is often called the extent of cancer. Information from tests is used to find out the size of the tumour, where the cancer started, whether the cancer has spread from where it first started and where the cancer has spread. Your healthcare team uses the stage to plan treatment and estimate the outcome (your prognosis).
The most common staging system for GISTs is the TNM system. For GISTs there are 4 stages. Often the stages 1 to 4 are written as the Roman numerals I, II, III and IV. Generally, the higher the stage number, the more the cancer has spread. Talk to your doctor if you have questions about staging.
When describing the stage, doctors may use the words localized or metastatic. Localized means that the cancer is only in the organ or close to where it started and has not spread to other parts of the body. Metastatic means in a part of the body farther from where the GIST started.
The stages of GISTs also depend on the mitotic rate, which shows how quickly the cancer cells grow and divide.
Find out more about staging cancer.
Stages of GISTS of stomach and omentum
Stage 1A – The tumour is 5 cm or smaller with a low mitotic rate.
Stage 1B – The tumour is larger than 5 cm, but not more than 10 cm. It has a low mitotic rate.
Stage 2 – The tumour is 5 cm or smaller with a high mitotic rate. Or the tumour is larger than 10 cm with a low mitotic rate.
Stage 3A – The tumour is larger than 5 cm, but not more than 10 cm. It has a high mitotic rate.
Stage 3B – The tumour is larger than 10 cm with a high mitotic rate.
Stage 4 – The cancer has spread to nearby lymph nodes or to other parts of the body (distant metastasis), such as to the liver or peritoneal cavity. This is also called metastatic cancer. The cancer has a low or high mitotic rate.
Stages of GISTS of small intestine, esophagus, colon, rectum, mesentery and peritoneum
Stage 1 – The tumour is 5 cm or smaller with a low mitotic rate.
Stage 2 – The tumour is larger than 5 cm, but not more than 10 cm. It has a low mitotic rate.
Stage 3A – The tumour is 2 cm or smaller with a high mitotic rate. Or the tumour is larger than 10 cm with a low mitotic rate.
Stage 3B – The tumour is larger than 2 cm with a high mitotic rate.
Stage 4 – The cancer has spread to nearby lymph nodes or other parts of the body, such as to the liver. This is also called metastatic cancer. The cancer has a low or high mitotic rate.
Recurrent GIST means that the cancer has come back after it has been treated. If it comes back in the same place or close to where the cancer first started, it’s called local recurrence. It can also recur in another part of the body. This is called a metastatic GIST.
GIST cells can spread from the GI tract to other parts of the body and develop into new tumours. The new tumour is called a metastasis or secondary tumour. If more than one tumour develops in another part of the body, they are called metastases.
Understanding how a type of cancer usually grows and spreads helps your healthcare team plan your treatment and future care. If GISTs spread, they are most likely to spread within the abdomen, particularly to the liver or peritoneal cavity (the space in the abdomen that contains the stomach, liver and intestines). GISTs can also spread to the lungs or bones, but this is uncommon.
GISTs behave differently than other types of soft tissue sarcoma, so they are treated differently. When deciding which treatments to offer for GISTs, your healthcare team will consider:
if the tumour is larger than 2 cm whether or not the tumour is in the stomach
if the tumour is cancerous (malignant) or non-cancerous (benign)
if it is high or low grade stage your overall health
Surgery is usually the main treatment for a GIST that hasn’t spread. The goal of the surgery is to completely remove all of the cancer. Depending on the location of the tumour, the surgeon may also need to remove parts of nearby organs or tissues. Lymph nodes near the tumour are usually not removed because GISTs don’t often spread to the lymph nodes.
GISTs in the stomach
Surgery is the main treatment for GISTs in the stomach. The entire tumour and a margin of healthy tissue around it are removed. The types of surgery used may include:
- wedge resection
- partial or total gastrectomy (part or all of the stomach is removed)
- removal of any nearby organs, such as the spleen, pancreas or diaphragm, that contain cancer
GISTs in the small intestine
Surgery is also the main treatment for GISTs in the small intestine. Different types of surgery may be done depending on where the GIST is in the small intestine. The types of surgery used may include:
- bowel resection
- partial removal of the duodenum (the first part of the small intestine) with reconstruction
- Whipple procedure, or pancreaticoduodenectomy
Imatinib (Gleevec) is a biological therapy drug used to treat GISTs. Biological therapy uses natural or artificial substances that change the way cells behave. Imatinib is also called a targeted therapy. Targeted therapy uses drugs to target specific molecules (such as proteins) on the surface of cancer cells. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells while limiting harm to normal cells. Imatinib blocks tyrosine kinase, which is an enzyme that the tumour needs to grow. Because it blocks this enzyme, imatinib is called a tyrosine kinase inhibitor.
Imatinib is used to treat GISTs that:
- can’t be removed with surgery (are unresectable)
- have come back after treatment, or recurred
- have spread, or metastasized, to other parts of the body
Imatinib may also be used to shrink a tumour that is borderline resectable. This is done to make it possible to remove the tumour with surgery. It may also be done so the surgeon doesn’t have to completely remove organs that the GIST has grown into. For example, imatinib may be used to shrink GISTs in the rectum that have grown into the bladder or prostate so these organs don’t have to be removed.
Imatinib may be given after surgery when doctors think there is a high risk that the GIST will come back, or recur. Large or high-grade tumours or those that rupture (break open) during removal are usually considered high risk.
Imatinib is taken by mouth, usually every day for up to 3 years. Researchers are still studying this drug to find out how long people should take it for best results. Unfortunately, tumours may no longer respond to the imatinib or may become resistant to it when it is taken for a long time. If imatinib is no longer effective, you may be offered second-line drug therapy.
Second Line Drug Therapy
Sunitinib (Sutent) is another tyrosine kinase inhibitor. It works by stopping the tumour from creating new blood vessels. The process of making new blood vessels is called angiogenesis. Because sunitinib prevents blood vessels from forming, it is called an anti-angiogenic drug.
Sunitinib may be used when the cancer doesn’t respond to imatinib. It may also be used if you can’t tolerate imatinib. Sunitinib is not as “selective” as imatinib as it inihibits many other growth pathways. Therefore, people often experience a broader range of side effects when using sunitinib.
External beam radiation therapy may be offered to relieve symptoms of advanced disease, such as pain or bleeding (palliative radiation therapy).
Treatment options for GISTs that come back, or recur, after treatment depend on where the cancer comes back and how much cancer is in the body. For most recurrences, imatinib will be used because it offers the best chance of shrinking tumours. If imatinib does not work at first, the doctor may increase the dose or try sunitinib instead. Your healthcare team may also consider surgery to remove recurrent GISTs in certain situations.
For more detailed information on specific drugs, go to sources of drug information
Tumours of uncertain tissue type
Tumours are usually named and grouped based on the type of normal cells the cancer cells look like under a microscope. Many soft tissue sarcomas contain different types of cells. Some sarcomas are made of cells that do not look like any type of cell found in normal tissues. These tumours often have more immature cells, which haven’t developed into specialized cells that do certain jobs. This means that it may be difficult to tell what type of cell they started in. These include:
- alveolar soft-part sarcoma is a rare tumour. It usually occurs in young adults and affects women more often than men. This type of tumour most commonly develops in the legs. It grows slowly, but it is known to spread, or metastasize, to the lungs, brain or bones in the early stages.
- Clear cell sarcoma is a rare, slow-growing tumour. It usually develops in the tendons of the arms or legs in young adults. In many cases, this cancer has already spread to other parts of the body when it is diagnosed.Clear cell sarcoma is similar to melanoma in some ways. For example, it contains brown pigment (melanin) similar to melanoma. For many years, clear cell sarcomas were thought to be a melanoma rather than a soft tissue sarcoma. But clear cell sarcomas have specific genetic changes that set them apart from melanoma.
- Desmoplastic small round cell tumour is a rare soft tissue sarcoma. It most often affects children, adolescents and young adults. It usually occurs in the fibrous tissue in the abdomen. The tumour is made up of small, round cancer cells surrounded by scar-like tissue.
- Epithelioid sarcoma most often develops in soft tissues under the skin of the upper extremities, often in a finger, hand or forearm. It usually affects adolescents and young adults. This type of cancer commonly spreads to the lymph nodes and lungs
- Ewing sarcoma usually develops in bone (see Ewing sarcoma). But about one-third of Ewing sarcomas are found in soft tissues. These include extraskeletal Ewing sarcoma and peripheral primitive neuroectodermal tumour (pPNET).
- Extraskeletal Ewing sarcomastarts in the soft tissues around the bones. They can start anywhere in the body, but usually occur in the trunk, extremities (legs and arms), head and neck. Extraskeletal Ewing sarcomas tend to behave differently from other soft tissue sarcomas. The cells of these tumours look and act very much like Ewing sarcoma of the bone, so they are usually treated like bone sarcoma.
- pPNETis very rare. It can occur anywhere, but it usually develops in the chest, abdomen, pelvis and extremities (legs and arms). pPNETs share many features with Ewing sarcoma of the bone and extraskeletal Ewing sarcoma and are usually treated like bone sarcoma.
Ewing sarcoma usually develops in bone (see Ewing sarcoma). But about one-third of Ewing sarcomas are found in soft tissues. These include extraskeletal Ewing sarcoma and peripheral primitive neuroectodermal tumour (pPNET)
- Malignant mesenchymoma is a rare type of soft tissue sarcoma. These tumours have features of fibrosarcoma and at least 2 other types of soft tissue sarcoma.
- Malignant PEComa gets its name from its mixture of perivascular and epithelioid cells. PEComa is usually non-cancerous, or benign. It can also be cancerous, or malignant, which means that it can spread, or metastasize, to other parts of the body.
- Spindle cell tumour and spindle cell sarcoma don’t look like any type of specific cancer, which means that doctors can’t give a specific diagnosis. The tumour may be considered a sarcoma or another type of cancer that looks like a sarcoma under the microscope.
- Synovial Sarcoma is a cancerous, or malignant, tumour that develops in synovium which is the synovial tissue lining the joints. This is an uncommon tumor that usually develops in children or young adults, and it develops more often in boys than in girls.
These tumours can spread or metastasize, to the skin, particularly the scalp.This reason, they are sometimes classified as a sarcoma of uncertain (unknown) origin.
Soft Tissue Sarcomas: Treatment Options
Descriptions of the most common treatment options for sarcoma are listed below. Treatment options and recommendations depend on several factors, including the type, stage, and grade of sarcoma, possible side effects, and the patient’s preferences and overall health. Your care plan may also include treatment for symptoms and side effects, an important part of cancer care. Take time to learn about all of your treatment options and be sure to ask questions about things that are unclear.
· Surgery : Surgery is the removal of the tumor and some surrounding healthy tissue during an operation. Before surgery, it’s important to have a biopsy and appropriate imaging to confirm the diagnosis After a biopsy, surgery is typically the first and main treatment for STS that is small and located in only 1 area. Surgical oncologists and orthopedic oncologists are doctors who specialize in treating STS using surgery. The surgeon's goal is to remove the tumor and enough normal tissue surrounding it to obtain a clean margin around the tumor. A “clean margin” means there are no tumor cells visible at the borders of the surgical specimen. This is currently the best method available to ensure that there are no tumor cells left in the area from which the tumor was removed. Small low-grade sarcomas can usually be effectively removed by surgery alone. Those that are high grade and larger than 2 inches (5 cm) are often treated with a combination of surgery and radiation therapy. Radiation therapy or chemotherapy may be used before surgery to shrink the tumor and make removal easier. They also may be used during and after surgery to destroy any remaining cancer cells. Rarely, for patients with a very large tumor involving the major nerves and blood vessels of the arm or leg, surgical removal of the limb, called amputation, is required to control the tumor. This can also be necessary if the tumor grows back in the arm or leg after surgery, radiation therapy, and/or chemotherapy have been completed. It’s important to remember that the operation that results in the most useful and strongest limb may be different from the one that gives the most normal appearance. If amputation is needed, rehabilitation, including physical therapy, can help maximize physical function. Rehabilitation can also help a person cope with the social and emotional effects of losing a limb. Patients who have had an amputation can often wear a prosthesis, depending on the type of amputation.
· Radiation Therapy: Radiation therapy is the use of high-energy x-rays or other particles to destroy cancer cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. Since sarcoma is rare, it is very important to talk with a radiation oncologist who has experience treating sarcoma. A radiation therapy regimen, or schedule, usually consists of a specific number of treatments given over a set period of time.
Radiation therapy may be done before surgery to shrink the tumor so that it may be more easily removed. Or it may be done after surgery to remove any cancer cells left behind. Radiation treatment may make it possible to do less surgery, often preserving critical structures in the arm or leg if the sarcoma is located in one of those places.
Radiation therapy can damage normal cells, but because it is focused around the tumor, side effects are usually limited to those areas.
External Beam Radiation Therapy
The most common type of radiation treatment is called external-beam radiation therapy, which is radiation given from a machine outside the body.
The way external-beam radiation is used has changed over the past 20 years. It is now possible to give many small beams of radiation that turn on and off as the radiation machine rotates around the body. This is called intensity modulated radiation therapy (IMRT) and is now typically used for sarcomas. IMRT focuses more radiation on the tumor site and less on the normal tissues. As a result, there are fewer side effects than there were in the past.
Brachytherapy is the insertion of radiation seeds through thin tubes called catheters directly into the affected area of the body. Brachytherapy usually requires specialized skills and special training. It is only used in certain hospitals. The setup for brachytherapy usually starts in the operating room, where the catheters are placed. Tiny seeds of radioactive material, called low-dose-rate radiation seeds, are then slid into the tubes on wires for a set amount of time. At the end of the treatment, which lasts several days, both the radiation seeds and catheters are removed. People usually have to stay in the hospital to make sure the seeds do not move and accidentally expose a different area of the body to radiation.
Proton Beam Radiation Therapy
Proton therapy is a type of external-beam radiation treatment that uses protons rather than x-rays. Like x-rays, protons can destroy cancer cells. It is most commonly used in parts of the body close to critical structures, for example near the spinal cord or at the base of the brain.
Intraoperative Radiation Therapy
In some hospitals, part of the planned radiation therapy can be given during surgery. This approach can decrease the need to expose normal tissue to radiation from external-beam radiation or with brachytherapy.
Side Effects of Radiation Therapy
Side effects from radiation therapy depend on what part of the body receives radiation. They may include fatigue, mild skin reactions, upset stomach, and loose bowel movements. In the short term, radiation can cause injury to the skin that looks like a sunburn. This is usually treated with creams that keep the skin soft and help relieve discomfort. Radiation therapy can also affect wound healing. In the long term, radiation can cause scarring that affects the function of an arm or a leg. In rare cases, radiation can cause a sarcoma or other cancer. In the unlikely event that this happens, it takes an average of about 10 years after radiation for a second cancer to develop. Each person is encouraged to talk with his or her doctor about the possible risks and benefits of a specific treatment such as radiation therapy. Most side effects go away soon after treatment is finished.
Chemotherapy is medication that destroys cells that are growing and dividing. Cancer cells grow by dividing, and they grow faster than normal cells. However, normal cells also grow and divide, so the side effects of chemotherapy are due to the treatment’s effects on normal cells that are growing and diving. Chemotherapy is given by a medical oncologist, a doctor who specializes in treating cancer with medication.
Systemic chemotherapy gets into the bloodstream to reach cancer cells throughout the body. Common ways to give chemotherapy include an intravenous (IV) tube placed into a vein using a needle or in a pill or capsule that is swallowed (orally).
A chemotherapy regimen, or schedule, usually consists of a specific number of cycles given over a set period of time. A patient may receive 1 drug at a time or combinations of different drugs given at the same time. Chemotherapy for sarcoma can usually be given as an outpatient treatment.
Different drugs are used to treat different types and subtypes of sarcoma. Some types of chemotherapy that might be used alone or in combination for STS include:
- Dacarbazine (DTIC-Dome)
- Docetaxel (Taxotere)
- Doxorubicin (Adriamycin)
- Epirubicin (Ellence)
- Eribulin (Halaven)
- Gemcitabine (Gemzar)
- Ifosfamide (Cyfos, Ifex)
- Liposomal doxorubicin (multiple brands)
- Methotrexate (Trexall)
- Olaratumab (Lartruvo)
- Temozolomide (Methazolastone, Temodar)
- Trabectedin (Yondelis)
- Vinblastine (Velban)
- Vincristine (Oncovin, Vincasar)
In some cases, a specific drug or drugs are used for a particular type of sarcoma. Since there are over 50 types of STS, it is not possible to list them all here. Here are 2 examples:
- Cyclophosphamide (Cytoxan, Clafen, Neosar)
- Dactinomycin (Cosmegen)
- Etoposide (VePesid, Toposar)
- Irinotecan (Camptosar)
- Temozolomide (Temodar)
- Bevacizumab (Avastin)
- Docetaxel (Docefrez, Taxotere)
- Paclitaxel (Taxol)
- Pazopanib (Votrient) or related oral medicines
Chemotherapy is often used when a sarcoma has already spread. It may be given alone or in combination with surgery, radiation therapy, or both.
For example, certain types of sarcoma may be treated with chemotherapy before surgery to make the tumor easier to remove. Chemotherapy given before surgery may be called by different names, including preoperative chemotherapy, neoadjuvant chemotherapy, or induction chemotherapy.
If a patient has not received chemotherapy before surgery, chemotherapy may be given to destroy any microscopic tumor cells that remain after a patient has recovered from surgery. Chemotherapy given after surgery is called adjuvant chemotherapy or postoperative chemotherapy.
The side effects of chemotherapy depend on the individual and the dose used, but they can include fatigue, risk of infection, nausea and vomiting, hair loss, loss of appetite, and diarrhea. These side effects usually go away after treatment is finished. Learn more about the basics of chemotherapy and preparing for treatment. The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications.
Targeted therapy is a treatment that targets the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival, usually by blocking the action of proteins in cells called kinases. This type of treatment blocks the growth and spread of cancer cells while limiting damage to healthy cells.
Added Care needed for Cancer Patients
Cancer and its treatment often cause side effects. In addition to treatments intended to slow, stop, or eliminate the cancer, an important part of cancer care is relieving a person’s symptoms and side effects. This approach is called palliative or supportive care, and it includes supporting the patient with his or her physical, emotional, and social needs.
Palliative care is any treatment that focuses on reducing symptoms, improving quality of life, and supporting patients and their families. Any person, regardless of age or type and stage of cancer, may receive palliative care. It works best when palliative care is started as early as needed in the cancer treatment process. People often receive treatment for the cancer at the same time that they receive treatment to ease side effects. In fact, patients who receive both at the same time often have less severe symptoms, better quality of life, and report they are more satisfied with treatment.
Palliative treatments vary widely and often include medication, nutritional changes, relaxation techniques, emotional support, and other therapies. You may also receive palliative treatments similar to those meant to eliminate the cancer, such as chemotherapy, surgery, or radiation therapy. Talk with your doctor about the goals of each treatment in the treatment plan.
If cancer spreads to another part in the body from where it started, doctors call it metastatic cancer. If this happens, it is a good idea to talk with doctors who have experience in treating it.
Remission and chance of Recurrence
A remission is when cancer cannot be detected in the body and there are no symptoms. This may also be called having “no evidence of disease” or NED.
A remission may be temporary or permanent. This uncertainty causes many people to worry that the cancer will come back. While many remissions are permanent, it’s important to talk with your doctor about the possibility of the cancer returning. Understanding your risk of recurrence and the treatment options may help you feel more prepared if the cancer does return.
If the cancer does return after the original treatment, it is called recurrent cancer. It may come back in the same place (called a local recurrence), nearby (regional recurrence), or in another place (distant recurrence). If the sarcoma was originally in the arm or leg, the recurrence most commonly occurs in the lungs. Patients treated for sarcoma of the abdomen or torso are at risk for local, regional, or distant recurrence.
When this occurs, a new cycle of testing will begin again to learn as much as possible about the recurrence. After this testing is done, you and your doctor will talk about your treatment options. Often the treatment plan will include the treatments described above, such as surgery, chemotherapy, and radiation therapy, but they may be used in a different combination or given at a different pace. Your doctor may suggest clinical trials that are studying new ways to treat this type of recurrent cancer. Whichever treatment plan you choose, palliative care will be important for relieving symptoms and side effects.
Local recurrences often can be successfully treated with additional surgery plus radiation therapy, but the risks of side effects from these treatments tends to increase. Treatment for a distant recurrence is most successful when there are a small number of tumors that have spread to the lung that can be completely removed surgically, destroyed with radiofrequency ablation (see below), or destroyed with ablative high-dose radiation therapy (also known as stereotactic body radiotherapy, SBRT, or gamma-knife radiotherapy):
- Radiofrequency ablation is a technique where a needle is inserted into the tumor to destroy the cancer with an electrical current. This burns the tumor from the inside out.
- SBRT is the use of pinpointed radiation at very high doses over a few treatments to attack a specific small area of tumor. This is a useful technique because it uses fewer treatments and can be more precise than external-beam radiation therapy.
People with recurrent cancer often experience emotions such as disbelief or fear. Patients are encouraged to talk with their health care team about these feelings and ask about support services to help them cope.