Understanding metastatic cancer

Cancer is a disease characterised by the uncontrolled division of abnormal cells. It usually develops at a single site initially, and may display metastatic symptoms at a later stage. During metastasis, cancer cells break away from the tumour in the primary site and travel to other parts of the body through the bloodstream or the lymphatic system. Though they can be controlled, metastatic cancers require aggressive treatment as the cancer cells can be widespread, explains Dr N. Jayalatha, the director of the MNJ Institute of Oncology and Regional Cancer Centre.

Q. What happens when a cancer is metastatic? Does it mean that all the organs of the body get affected?

Metastatic cancer is an advanced cancer in which the disease spreads from the primary site to other organs. This does not mean it spreads to all organs. For example, if the cancer is in the breast, it may spread to the lungs and the underarm lymph nodes; if it is in the colon, it may spread to the liver; and if it in the lungs, it may spread to the liver, or the bones, or both.

Q. Do metastatic cancers not show any symptoms in the early stages, when they are confined to the primary site?

Primary cancers grow slowly and manifest symptoms later. The immune system fights these cells, but usually, there isn’t a heightened response. Most patients seek medical advice when the disease reaches stage 2 or stage 3. By then, the cancer is fully developed, and in many cases, it has already affected adjoining organs.

Often, symptoms in the early stages are minimal. They’re usually ignored by patients and even their family doctors. For this reason, cancer screening is recommended for those who have a family history of the disease. Screening helps in early detection and treatment.

Q. Can primary cancers be diagnosed?

Yes, primary cancers have been identified in head and neck, breast and cervical cancer patients. Regular screening by people who are cautious and aware have led to early detection. People above the age of 40 should have mammograms, pap smears and VIA for cervical cancer conducted once every two years, and tests like chest x-rays, occult blood tests, and ultrasounds once every year.

Q. What are the challenges to early diagnosis?

 We find that there isn’t an acceptance of the disease. People are careless, and a major constraint is finances. There is also a stigma associated with cancers of the head and neck, cervical cancer, etc. Individuals are more worried about how their families will react if they’re diagnosed. They’re not able to accept the disease at a personal level.

Q. What are the treatment outcomes in metastatic cancer? Are there chances of relapse?

Metastatic cancer is usually treated with chemotherapy and radiation. Immunotherapy and target therapy are also used. Surgery is not very common.

Treatment modules concentrate on controlling the cancer rather than curing the disease. The aim is to reduce pain and improve the patient’s quality of life. Advanced cancer requires the removal of cancer cells from all the places that it has spread to, and hence treatment has to be aggressive to avoid relapse.

Symptoms that you shouldn’t ignore:

• Prolonged pain in specific parts of the body
• Unexplained weight loss
• Change in bowel or bladder habits
• Unusual bleeding or discharge
• Hoarseness in the voice or a persistent cough

How the disease spreads

• Cancer cells use the lymph vessels, which are very much like blood vessels, to travel through the body. Lymph vessels carry a clear fluid and cells of the immune system. Here, cancer cells often trigger the immune system to fight the disease.
• Cancer cells that have broken off from the primary tumour can also travel through blood vessels. Many of them die there, but some may settle in other parts of the body and grow into new tumours.
• The growth and spread of cancer cells is a slow process. They often have to work hard to avoid the attacks of the immune system in their attempt to thrive and spread within the body.