Department of Musculoskeletal Oncology

Bone sarcomas are primary bone cancers and rare, accounting for about 0.2% of all malignant tumours. They are common in children, teenagers, and young adults, although much less commonly, they can occur in the older age group of patients. The exact aetiology is still unknown. The commonest types of bone sarcomas are osteosarcoma, Ewing's sarcoma, and chondrosarcoma. They can arise at any site in the body, although they are most commonly in limbs and the pelvis. Initial symptoms usually include:

  Non-mechanical pain (pain when not doing any activity).

  Swelling of the affected bone.

   A fracture due to very minimal trauma.

Malignant bone sarcomas are aggressive tumours usually treated with a combination of surgery and long courses of adjuvant therapy, mainly chemotherapy. Modern surgery aims at limb salvage surgery (preserving the limb function following removal of primary tumour, while at the same time preserving the limb function (or another body part) wherever possible. Limb-salvage surgery is usually done by replacing the bone with endoprosthesis or employing biological methods of reconstruction. Radiotherapy is sometimes used after surgery or instead of surgery if a surgical option is not viable.Aggressive benign tumours like giant cell tumours are managed well with intralesional curettage surgery.

Soft tissue sarcomas account for less than 1% of all malignant tumours. The cause of these tumours is not known, although they may be associated with previous radiotherapy, some toxins, and very rarely, may be hereditary. They can affect any age group, although they are more common in the middle-aged and elderly and less common in younger age groups. There are many different histological subtypes of soft tissue sarcomas, although the commonest include undifferentiated pleomorphic sarcoma, liposarcoma, myxofibrosarcoma, synovial sarcoma, leiomyosarcoma, and malignant peripheral nerve sheath tumour. Nearly 60% of soft tissue sarcomas arise in the arms or legs. The commonest sarcoma arising from the gut is gastrointestinal stromal tumour (GIST). The signs and symptoms of sarcomas are often the first sign of a lump in an arm or leg. Worrying features that might indicate a sarcoma include a size greater than 5cm, a lump increasing in size, and increasing pain. Radiotherapy is usually indicated as adjuvant therapy in managing soft-tissue sarcomas.

The most important part of diagnosis in sarcoma is to take a sample of the tumour, called a Biopsy. Biopsy is best done by trained specialists as incorrect procedures can compromise limb salvage. A pathologist examines the biopsy under a microscope to confirm whether there is cancer and to grade the type of sarcoma if present based on aggressiveness. Most biopsies are done under anaesthesia using ultrasound or fluoroscopy in theatre. CT-guided biopsies too are done for suspected tumours in anatomically challenging areas. Immunohistochemistry and Molecular genetics to identify characteristic chromosomal translocations and gene mutations (abnormalities of the genetic material) now are advances in sarcoma diagnosis.

Imaging/Scanning is essential to determine whether the tumour has spread anywhere else in the body or is confined only to the primary site. This is called Staging. Soft-tissue sarcomas of limbs most likely spread into the lungs, whereas those of the abdomen or colon commonly spread into the liver. Bone sarcomas most commonly spread to the lungs and bones. Staging scans may include MRI scans, CT scans, bone scans and PET scans.