Sarcomas are rare cancers that develop in the supporting or connective tissues of the body such as muscle, bone, nerves, cartilage, blood vessels and fat.
There are around 3200 new cases of sarcoma diagnosed each year in the UK.
Sarcomas are some of the commonest childhood cancers.
Most sarcomas (about 55%) affect the limbs, most frequently the leg. About 15% affect the head and neck area or are found externally on the trunk, while the remainder will be found internally in the retroperitoneum (abdominal area).
Sarcomas fall into three broad categories;
Soft tissue cancers
Primary bone cancers
Gastro-intestinal stromal tumours (a type of soft tissue sarcoma found in the stomach and intestines commonly known as GIST)
There are around 70 different sub-types of sarcoma within these broad categories. These sub-types are determined by the tissue of origin (the tissue in the body where the tumour originally formed), genetic characteristics or by other molecular analysis undertaken by expert pathologists.
Sarcomas often don’t cause any symptoms for a long time. They can start in any part of the body and the symptoms will depend on the part of the body that is affected.
If the sarcoma is in an arm or a leg, the most common symptom is an uncomfortable swelling in the affected limb. 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 will depend on which organ in the body is affected. For example:
a sarcoma in a lung may cause a cough and breathlessness
a sarcoma in the abdomen could cause abdominal pain, vomiting and constipation. A GIST may also cause bleeding into the bowel causing you to vomit blood, pass dark bowel motions or develop symptoms of anaemia (low number of red blood cells), such as shortness of breath or tiredness
a sarcoma affecting the womb may cause bleeding from the vagina and pain in the lower part of the abdomen.
Usually, soft tissue sarcomas don’t cause any symptoms until they are quite large and are pressing on an organ in the body or on a nerve or muscle. Things to look out for include:
any lump, especially if it is increasing in size and is bigger than 5cm (2in)
any lump that is painful or tender
any lump that is deep in the body (ie not just under the skin)
any lump that has come back after being surgically removed.
If you notice any of the above, contact your GP; but remember that these symptoms can also be caused by other conditions.
As with other cancers, treatment for sarcomas depends on the size, type, location and stage of the sarcoma, including whether it has spread to the lymph nodes or other parts of your body, and your overall health.
Surgery is the most common treatment for soft tissue sarcomas, especially if malignant cells haven't spread to other parts of the body. Surgery generally involves removing the cancer and some healthy tissue surrounding it. If the sarcoma has spread, surgical removal of the primary and secondary tumors may be possible.
Previously, amputation was a common treatment for soft tissue sarcomas in an arm or leg. Today, advances in surgical techniques and the combination of chemotherapy and radiation before surgery (neoadjuvant chemoradiotherapy) or after surgery (adjuvant chemoradiotherapy) make limb-sparing surgery possible in most cases. However, amputation may be necessary to remove all of the malignant cells from soft tissue sarcoma in an arm or leg that has invaded nerves, arteries or muscles.
Radiation therapy — also called radiotherapy or X-ray therapy — involves treating cancer with beams of high-energy particles, such as gamma rays or X-rays. Although radiation can affect healthy cells as well as cancer cells, it's much more harmful to cancer cells. In addition, normal cells can recover from the effects of radiation more easily than cancer cells can.
Radiation therapy may be recommended to treat your soft tissue sarcoma. Your doctor may suggest using radiation therapy before or after surgery to stop the growth of any remaining cancer cells. You may also receive chemotherapy at the same time as radiation in an effort to make the radiation more effective.
Side effects from radiation treatment depend on the area that's being treated, but may include fatigue, skin problems, headache, swelling, weakness, nausea, vomiting and slower healing after surgery.
Chemotherapy uses medications to kill rapidly dividing cells. These cells include cancer cells, which continuously divide to form more cells, and healthy cells that divide quickly, such as those in your bone marrow, gastrointestinal tract, reproductive system and hair follicles. Unlike radiation therapy, which treats only the part of your body exposed to the radiation, chemotherapy treats your body as a whole (systemically). As a result, it treats cells that may have spread beyond where the cancer originated.
The role of chemotherapy in the treatment of soft tissue sarcoma isn't clear, because not all studies have had positive results. However, chemotherapy has been found effective in treating rhabdomyosarcomas.
In addition to chemotherapy, some drugs inhibit certain enzymes that are critical to the development and growth of a tumor. One of these drugs, imatinib (Gleevec), is used to treat a type of sarcoma called gastrointestinal stromal tumor. Other types of cancer-fighting drugs and new combinations of treatments are being studied in clinical trials.
Possible side effects from chemotherapy include nausea, vomiting, hair loss, mouth sores, fatigue, increased risk of infection, weakness and increased bleeding.