What is cancer?
Cancer is when some cells in the body change and grow out of control. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them, and die when your body does not need them any longer. Cancer is made up of abnormal cells that grow even though your body doesn't need them. In most types of cancer, these abnormal cells cause harm to the body and may spread to other parts of the body. There are many kinds of cancer and each may have it's own unique behaviour and treatment.
What causes cancer?
Two types of factors contribute to the cause of cancer. One is a tendency or predisposition to develop cancer, which in some cases is inborn in the patient. As people age the risk for cancer increases since older cells have a higher chance of going wrong. The other is exposure to external triggers that start it off (Ex: Tobacco, alcohol, environmental toxins, excess sun exposure, HIV or Hepatitis infections, etc.)
Why do some people get cancer and not others?
A small proportion of people may have inherited or acquired genetic mutations that makes that person's cells have a low threshold for becoming malignant. So that person will develop a cancer with relatively less prompting by a trigger such as tobacco or alcohol or the sun, than another person whose cells have a higher threshold and who may be able to tolerate more exposure to a trigger without developing a cancer. Also, some people may have longer and stronger exposure to external triggers such as tobacco, alcohol, environmental toxins, excess sun exposure, etc., than others.
Do we get cancer from what we eat?
The high-fat, low-fiber diet common in developed countries may play a role in about a third of all cancers. High temperature cooking (deep frying), certain artificial sweeteners, etc. are suspected of increasing cancer risk but there is no definite proof yet. A bad diet and sedentary lifestyle cause obesity, which is definitely linked to increased risk of several cancers.
Are chemicals and pollutants causing cancer?
In certain jobs or certain areas, prolonged exposure to a few chemicals may cause certain rare kinds of cancers. Nowadays almost all of these substances have been identified and are regulated in the west. High environmental pollution, poor safety practices and lack of awareness continue to cause problems in India.
Does tobacco really cause cancer?
Yes. Tobacco used in any form or shape cause a vast number of cancers of the head & neck, lung, bladder, pancreas, mouth, larynx, esophagus, and kidney.
Can cancer be prevented?
A lot of them can. Established preventive methods, including not smoking, preventing sun damage, practicing safe sexual behavior, eating a high-fiber, low-fat diet, regular exercise and having regular Pap smear tests/ Mammograms/ other screening tests would reduce the incidence of cancer. It's important to note that many people who develop cancer don't have any known risk factors.
Why does the diagnosis seem to be so delayed in so many cases?
Cancer cells can multiply to produce literally billions of cells before a tumor becomes big enough to detect or cause symptoms. That is why prevention and some methods of screening are so important.
Why do people with the same cancer get different treatment and have different problems?
There are a wide variety of cancers that occur in a wide variety of individuals. Besides the cancers may be detected at different stages in different people. An expert Oncologist will decide on the ideal treatment for a given individual depending on the patient characteristics, cancer type, stage, other risk factors and a wide variety of other considerations. An important factor is also the patient's personal preference, choice and affordability. A good Oncologist will discuss these thoroughly with the patient and the family.
Is cancer curable?
Overall about 40% of all cancers are completely curable with proper treatment. Many more cancers can be controlled with a good quality and quantity of life. Even in those cases where cancer itself is no longer treatable, suffering and pain can be decreased. In this day and age, no one needs to suffer.
What is the conventional treatment of cancer?
Surgery, Radiation therapy and Chemotherapies are considered "conventional" treatments for cancers because they have been in use for many decades. For the vast majority of cases they are still very effective either alone or in combination. Modern advances in all three modalities have dramatically reduced side effects and increased their effectiveness in this era. Your doctor will be able to explain whether the chance of them working in your own case is high, low, or in-between. That is why the discussions you have with your doctor about your particular case are so important.
Why is the treatment so awful?
Modern treatments for cancer cause very few side effects in these eras, besides problems can be prevented or treated far better now in expert hands. However, some intensive treatments can still cause significant problems. Also there are individual variations in how different patients may tolerate the same kind of therapy. Treatment is troublesome mostly because cancer cells are only slightly different from normal cells. This is unlike say, bacterial infections such as pneumonia or tuberculosis where the bacterial cells are completely different from your body's cells and antibiotics can kill them while not affecting you very much. But because cancer cells are very like your normal cells, in order to kill them you may risk doing considerable damage to normal cells or tissues.
What is Targeted Therapy?
This is a new class of medicines which are designed to attack only specific targets found in certain kinds of cancers. They are effectively like guided missiles, which seek out specific laser-painted targets in a war. This increases the number of cancer cells, killed while sparing normal cells thus minimising side effects. This class of medicines became a part of the treatment armamentarium in the late 1990s and many new medicines are being added now.
What is Immunotherapy?
The human body has it's own defence mechanism called "Immunity" which usually does a great job protecting us from both infections and cancers. But many cancers grow by learning how to escape detection by our immune system. Immunotherapies are a very new class of medicines and techniques which can 'unmask' the cancer cells and then allow the immune system to kill the cancer effectively. This class seems to be very useful in many kinds of cancers and there is a lot of ongoing research on this topic. This class is very safe too and although unusual or serious side effects may occur, they are rare compared to the 'conventional' therapies.
What is personalised medicine?
As discussed above, there is a wide variety of genetic mutations in cancer cells that may influence their behaviour and susceptibility to treatment. Individual patients also may have mutations that influence how well they tolerate certain kinds of treatments. The Human Genome Project and newer laboratory techniques now allow us to rapidly detect a vast variety of genes in individual biopsy samples. This information, along with other more conventional considerations, may allow a decision on the most effective and the least problematic treatment strategy for a specific individual with a specific cancer type. Personalised Medicine has made a huge impact in many kinds of cancers, like lung, kidney, melanoma, etc. There is a tremendous amount of ongoing research in this field and very soon the "one size fits all" approach may disappear completely.
Why is cancer treatment so expensive?
Unfortunately,many, of the cancer treatments discussed above can be expensive and sometimes beyond the reach of the average Indian. This is because these modern advances are the result of tremendous amounts of very expensive research, which results in an initial high cost of the new medicines. Heavy dependence on a Corporate Hospital based healthcare system, inadequate insurance, inadequate access to specialist care, delayed diagnosis, unnecessary testing, unnecessary inpatient admissions, lack of awareness in both physicians and public all play a major role in driving up costs. One solution to this problem is to establish comprehensive cancer centres in underserved communities providing efficient early diagnosis, effective outpatient care, accessible at the patient's doorstep. Increasing awareness, educating key health givers, increasing insurance coverage, cost effective screening strategies will all help.