Sarcomas (derived from the Greek word meaning ‘fleshy growth’) are malignant tumours of the tissues that connect, support, or surround other structures and organs of the body. Examples include: muscles, tendons, fibrous tissues, fat, blood vessels, nerves, and synovial tissues (tissues around joints)
The most common soft tissue sarcoma is rhabdomyosarcoma, developing from muscle or fibrous tissue. Other types of soft tissue sarcomas that affect children are:
- Liposarcoma (originating in fat tissue)
- Synovial sarcoma (originating in synovial tissue, including linings of joint cavities and tendon sheaths)
- Fibrosarcoma (originating in fibrous tissue)
The highest peak incidence of sarcomas is in the first few years of life.
Signs and Symptoms
The signs at presentation of rhabdomyosarcoma are dependent on the tumour’s primary site of origin. The most common sites of origin are head and neck, and genitourinary. The most common head and neck symptoms are:
- Proptosis (forwardly displaced or ‘bulging’ eye)
- Nasal obstruction
- Blood stained nasal discharge.
The common genitourinary (bladder or testes) symptoms are:
- Dysuria (painful or difficult urination)
- Urinary obstruction
- Blood stained vaginal discharge.
The most common test to diagnose rhabdomyosarcoma is a biopsy (usually undertaken under general anaesthetic in children). A range of further tests (including CT and MRI scan, X-ray, and blood and bone marrow tests) may be undertaken to ascertain the exact position, size and stage of the cancer.
Treatment depends on the site, size and extent of the disease. Surgery may be the first option, with additional chemotherapy or radiotherapy. In the majority of cases aggressive chemotherapy is required.
Overall cure rates are approximately 60%, although this is dependent on size and spread at presentation. Metastatic disease (characteristically of the lung, liver, bone or bone marrow) present in about 15% of patients, is associated with a poor prognosis.