Understanding Sarcoma: Symptoms, Causes and Treatment

Dr.Parveen Jain, 5 mins read

Sarcoma is a general term that refers to a large group of cancer. This form of cancer occurs in the bones (bone sarcomas) and connective tissues (soft tissue sarcomas), like muscles, tissues, nerves and blood vessels.

Sarcoma can occur in any part of the body but most commonly occurs in the lower extremities (such as legs, ankles and feet), followed by the upper extremities (like the shoulder, arms) followed by the abdomen, pelvis, trunk, head and neck.

There are around 70 known types of sarcoma. Bone sarcoma has five types, i.e., osteosarcoma, chondrosarcoma, fibrosarcoma, chordoma and Ewing's sarcoma. Soft tissue sarcoma is categorised into 13 types:

• Angiosarcoma
• Myxofibrosarcoma
• Synovial sarcoma
• Leiomyosarcoma
• Kaposi's sarcoma
• Epithelioid sarcoma
• Liposarcoma
• Undifferentiated pleomorphic sarcoma
• Gastrointestinal stromal tumour (GIST)
• Rhabdomyosarcoma
• Dermatofibrosarcoma protuberans
• Solitary fibrous tumour
• Malignant peripheral nerve sheath tumours

It affects both adults and children. Soft tissue sarcoma usually occurs in adults, while bone sarcoma commonly occurs in children, teens, and people older than 65.    

Signs & Symptoms

The signs and symptoms vary based on the tumour's location, size, and other factors. For example, some sarcoma doesn't produce noticeable signs initially. Some sarcomas feel like lumps under the skin that may or may not hurt. The most common symptoms are:

• Lump or swelling which is firm or hard 
• Pain in bone, back and abdomen/pelvis
• Restricted joint movements 
• Pathological fractures 
• Constitutional symptoms like loss of appetite, unexplained weight loss, fever.

Causes

Although it's unclear what causes sarcoma, experts say cancer develops when a mutation occurs in the DNA within the cell. The cancer cells grow and divide uncontrollably and form a tumour. If left untreated, it travels to other body parts through the bloodstream or lymphatic system. It becomes difficult to treat when the tumour develops in regions other than the primary location (metastasis).

Risk Factors

• Genetic Conditions: Chromosomal mutation and certain inherited syndromes like neurofibromatosis type 1 and familial retinoblastoma can put you at risk of sarcoma.
• Radiation therapy: A person who underwent high doses of radiation therapy is more prone to sarcoma.
• Exposure to chemicals: Working in an environment polluted with arsenic or certain chemicals - used to make herbicides and plastics - increases the risk of sarcoma.
• Lymphedema: It is a chronic swelling in arms and legs caused by lymph fluid. This situation happens when the lymphatic system is blocked or damaged.
• Exposure to viruses: Herpesvirus 8 is a risk factor for Kaposi's sarcoma (type of sarcoma). The virus usually affects those with weak immunity.

Diagnosis

If you are experiencing the symptoms mentioned above, you should immediately consult a doctor. He will begin by asking you a few symptoms-related questions and conduct a physical examination. The doctor may also advise you for:

• Biopsy: The doctor will take a sample of cells from the tumour and then send it to a pathology lab where specialists analyse it to check for sarcoma. It is very important to get the biopsy done from a centre where it is routinely done to get the best outcomes of the disease.
• Imaging tests: You may be advised to have a MRI scan, CT scan, PET scan or ultrasound for further evaluation. This will help the doctor to see the inside of your body.
• Bone scan: The doctor will inject a small amount of radioactive material into the body to check for bone sarcoma.

The doctor may also determine the grade (G) of cancer based on the appearance of the cancerous cells. The more normal the cancer cell appears, the better the prognosis. Doctors use this information to know the cancer stage by assigning a number (1 to 4). The higher the number, the more cancer cells have spread throughout the body.

Treatment

Treatment of sarcoma depends on the tumour's location, size, and other factors.

• Surgery: The doctor may perform an operation to take the tumour out of the body. You can consult your doctor to know whether the surgery will work for you.
• Radiation: In this therapy, high-energy X-ray beams are used to shrink the tumour before surgery or kill the cancer cells left in the location after the surgery.
• Chemotherapy: It uses drugs to kill or slow down the growth of cancer cells. These medicines are given orally or intravenously.
• Targeted Therapy: This treatment involves the use of drugs or manmade versions of antibodies. Target therapy helps block the growth of new cancer cells without damaging the normal cells.

Also, Read: Cancer prevention 6 tips to reduce your risk