Is it an Osteosarcoma?
Osteosarcoma, though the commonest primary bone cancer, is fortunately rare. So rare, that most people haven’t even heard of it. The symptoms of osteosarcoma can be vague, and overlap with those of a range of much more common conditions. Picked up early, osteosarcoma is curable. Hence the need to know more about osteosarcoma.
Pain in the bone is the most common symptom of osteosarcoma. Swelling in the same area is another symptom. Rarely, there may be a fracture in a bone weakened by osteosarcoma. While pain and swelling can have other causes as well, a history of injury does not rule out a bone tumor as the cause of one’s symptoms. Hence, when pain and swelling do not get better with regular treatment, (rest/ pain medication) – the patient needs to be investigated further.
A clinical suspicion by an orthopaedic surgeon/ other doctor will prompt an examination of the affected part, and then an x ray and possibly an MRI. On these investigations, if the doctor thinks it might be a bone tumor, they would send the patient to an orthopaedic oncologist (a doctor who treats tumors and cancers in the bones, muscles, and joints).
Tests done for diagnosis of osteosarcoma
If the signs and symptoms are pointing to a bone tumor such as an osteosarcoma, these are the investigations usually asked for:
Plain x-ray: This is often the first test done if a doctor suspects a bone tumor. In the vast majority of cases, an x ray will give a fair idea of whether the bone tumor is cancerous or non-cancerous.
MRI scan: MRIs can show details about the bone and nearby tissues, namely the vessels, nerves and muscles. This helps the orthopaedic oncologist to plan for a biopsy and the final surgery as well.
CT scan: A CT scan of the limb is sometimes done to see greater details of the bone structures. A plain CT scan of the chest may be done to see if cancer has spread to the lungs.
Bone scan: A bone scan can help show if a cancer has spread to other bones in the body. After the lungs, bones are the second commonest organs to be affected by osteosarcoma spread.
PET scan: PET scans use a special kind of sugar that can be seen inside the body with a special camera. If there is cancer, this sugar shows up as “hot spots” where the cancer is found. This test can help show if the cancer has spread, as well as if the cancer is being helped by treatment. PET scans are sometimes done at the same time as a CT scan (known as a PET/CT scan).
Biopsy:An orthopedic oncologist should ideally perform this test. A small piece of tissue is taken out of the involved bone and sent for test- which confirms the diagnosis.