Have you ever heard of sarcoma? Some parents may not have an idea of it because of its rarity, so much so that it has been called the “forgotten cancer.” Sarcomas occur more commonly in children and accounts for only 1% of all adult malignant tumors, according to Dr Leon Foo, Consultant Orthopaedic Surgeon at Island Orthopaedics, a member of the Healthway Medical Group. Aside from being rare, Dr Foo shared that symptoms of sarcoma in children are often mistaken as growing pains or other common childhood conditions, causing them to be overlooked—or forgotten—until the sarcoma has grown significantly.
We asked Dr Foo more about sarcoma: what it is, its risk factors, as well as preventive and treatment measures.
Sarcoma: Definitions and types
Sarcoma came from a Greek word which means “fleshy growth,” a fitting description of what it is: a histologically diverse group of rare but aggressive tumours that develop from the connective tissues of one’s bodies.
There are different types of sarcomas:
- Soft tissue sarcomas occur in muscles, fat, blood vessels, nerves, and fibrous tissue.
- Bone sarcomas involve the bones. While sarcomas can develop in any part of the body, they commonly occur in the arms and legs.
Although there are various histological subtypes of sarcoma that can occur at any age, there are a few sarcoma subtypes that occur more frequently among children and adolescents.
- Rhabdomyosarcoma is a soft tissue sarcoma that can occur in the head, neck, genital organs, urinary organs, or limbs. The tumour may cause pain along with a mass or swelling.
- Osteosarcoma is a bone sarcoma that commonly occurs in adolescents. It can cause pain in the affected bone that may worsen at night or during activity. As the sarcoma grows, the general area around the bone will swell. The bone also weakens and pathological fractures can result from it.
- Ewing sarcoma is another bone sarcoma that also commonly occurs in adolescents. Symptoms include pain at the site of the tumour and persistent fever.
Diagnosis and causes
Sarcoma has no known causes, but most sarcoma cases are also believed to be caused by random cell mutation and not due to external causes. However, there are certain risk factors which may increase one’s chances of developing it. These include:
- Previous radiation therapy
- Family history of sarcoma or other cancers
- Weakened immune system
- Damaged lymphatic system
- Exposure to chemicals
To confirm the existence of a tumour, a series of tests is needed before final diagnosis. These include a physical examination to determine the size and shape of the lump, radiological imaging investigations, such as X-rays, MRI, and PET-CT scans, and a biopsy that obtains tumour tissue to confirm the existence of sarcoma and to assess which subtype of sarcoma it is.
Protecting your child from it may be challenging as there is no way to truly prevent the development of sarcoma. Minimising exposure to risk factors can help though, as well as early detection and diagnosis.
Some tips to help you maximise chances of recovery include:
- Awareness of the different types of paediatric sarcomas and their symptoms;
- Early consultation with the doctor if you find any unusual lump or swelling on your child’s body, even if it is painless.
The survival rate of kids who are diagnosed with sarcoma depends on when it was first detected and diagnosed. Remember that the earlier the diagnosis, the higher the chances of recovery and survival.
Early signs of sarcoma
Dr Foo advised parents to be vigilant and keep an eye on the following signs of the disease:
- For rhabdomyosarcoma, symptoms may not be that obvious. If the tumour is large enough, some common symptoms your child may experience include pain, headache and nausea, blood in the urine or faeces, earache, vomiting, abdominal pain, and constipation.
- For osteosarcoma, symptoms vary but an aching pain in the bone or joint is usually the first symptom. This pain may not be constant initially and may subside briefly before recurring. Over time, the pain worsens and persists, typically being worse at night or with physical activity. Other symptoms of osteosarcoma include difficulty moving, limping, painful swelling close to a joint, fever, weight loss, pathological fractures, and anaemia.
- For Ewing sarcoma, symptoms are very similar to osteosarcoma, such as recurring pain, swelling, unexplained fever, weight loss, and fatigue.
Note that even if your child exhibits these symptoms, it does not necessarily mean he or she has sarcoma. But whether the symptoms are a sign of sarcoma or not, parents should consult a doctor if any of the above symptoms persists or worsens.
Treatment for sarcoma
Treatment varies depending on the histological subtype and stage of the sarcoma, Dr Foo said. A patient’s treatment plan needs to be individualised and will often involve a multidisciplinary team of doctors. Patients may require a combination of treatment modalities, such as surgery, chemotherapy, immunotherapy, targeted therapy, and/or radiation therapy.
There are two possible scenarios:
- If detected early and the sarcoma is in a location that is easily operated on with minimal collateral/morbidity, surgery may be able to remove the tumour completely.
- If the sarcoma is in its later stages, the patient may have to undergo chemotherapy and radiation therapy first in order to reduce the size of the tumour before receiving surgery.
In some cases of Ewing sarcoma, stem cell transplant is another option wherein after undergoing chemotherapy and radiation therapy to destroy malignant cells in the bone marrow and blood, healthy stem cells from the donor can be transplanted to produce a new set of healthy bone marrow.