Cancer FAQs

Cancer is a general term used to describe cells that grow and spread around the body in an uncontrolled way. Our body is made up of millions of tiny cells which replace themselves whenever necessary. For example, they replace themselves when they get worn out, old or injured.

The cells of our bodies grow and multiply in a process known as cell division. It must be extremely tightly controlled if all the cells in our body are to grow in the right place, and for all our organs and tissues to function properly. If cells divide too quickly the consequences can be disastrous.

Cancer is essentially a disease of cell division. Uncontrolled cell division can have many causes, and can happen in any type of cell in the body, but it usually results from defects or damage in one or more of the genes involved in cell division. If these genes become damaged (mutated) in some way, for example by exposure to cigarette smoke or ultraviolet radiation, the cell can start to divide uncontrollably. These defective cells can multiply to form a lump of abnormal tissue called a tumor.

A malignant tumor is made up of cancer cells. When it first develops, this malignant tumor may be confined to its original site. This is known as a cancer in situ (or carcinoma in situ). If these cells are not treated, they may spread beyond their normal boundaries and into surrounding tissues, becoming invasive cancer. Some benign tumors are precancerous and may progress to cancer if left untreated. Other benign tumors do not develop into cancer.

For a cancer to grow bigger than the head of a pin, it must grow its own blood vessels. This is called angiogenesis. Sometimes cells move away from the original (primary) cancer, either by the local tissue fluid channels (lymphatics) or in the blood stream, and invade other organs. When these cells reach a new site, they may continue to grow and form another tumor at that site. This is called a secondary cancer or metastasis.

There is no one single cause for cancer. Scientists believe that it is the interaction of many factors together that producer cancer. The factors involved may be genetic, environmental, or constitutional characteristics of an individual.

Anything that damages the genes in our cells can ultimately cause cancer. The vast majority of cancers are caused by DNA damage that accumulates over a person’s lifetime (‘sporadic’ cancer). Cancers that are directly caused by genetic faults inherited from a parent are less common.

A risk factor is anything that may increase a person’s chance of developing a disease. A risk factor does not necessarily cause the disease, but it may make the body less resistant to it. The following risk factors and mechanisms have been proposed as contributing to the development of cancer.

Lifestyle Factor

Smoking, chewing tobacco, taking gutka and pan masala, high- fat diet, lack of exercise or exposure to chemicals (cancer-causing substances) in the work place over long periods of time may be risk factors for some adult cancers.

Genetic Factors

Family history, inheritance, and genetics may play an important role in some adult and childhood cancers. It is possible for cancer of varying forms to be present more than once in a family. Some gene alterations are inherited. However, this does not necessarily mean that the person will develop cancer. It indicates that chance of developing cancer increases. There are two important types of genes that, when mutated, can cause cancer-tumour suppressor genes and oncogenes.

Environmental Hazards

During the course of a day, we are continually exposed to things that damages our DNA. Things that damage the DNA are called carcinogens, and they include: Tobacco, Car exhausts fumes, the sun, Natural and manmade radiation, asbestos, pesticides, fertilizers.

Many of these things cause damage because they react with the molecules in our cells to form free radicals. Free radicals are highly damaging molecules, and can wreak havoc on the sensitive machinery inside a cell.

Age

Age is an important factor for cancer. Cancer can occur at any age, but the risk of developing cancer increases with age. Over 70% of all newly diagnosed cancers occur in people aged 60 years or more. This is because the longer we live, the greater the number of potentially cancer causing mutations in our DNA.

Viruses

Some viruses are linked to certain types of cancer. Possibly, the virus alters a cell in some way. This does not mean that these cancers spread from person to person like an infection, and does not mean that everyone infected with these viruses will develop cancer.

The chances of curing cancer increase with early detection. The Indian Cancer Society and other organizations recommend paying attention to seven warning signs of cancer:

• Changes in bowel or bladder habits

• Unusual bleeding or discharge

• A sore that does not heal

• Indigestion of difficulty swallowing

• A nagging cough or hoarseness

• A thickening or lump in the breast or elsewhere

• An obvious change in wart or mole

A physician can detect cancer by taking medical history, performing routine checkups, cancer screening tests, imaging techniques and tissue biopsy.

Cancer Screening is a set tests designed to detect cancer even when one doesn’t have any symptoms. These tests include:

• Digital rectal examination

• Pelvic examination

• Breast self-examination

• PAP test

• Mammography

There is no single test that can accurately diagnose cancer. The complete evaluation of a patient usually requires a thorough history and physical examination along with diagnostic testing. Many tests are needed to determine whether a person has cancer, or if another condition (such as an infection) is mimicking the symptoms of cancer. There are number of ways to diagnose cancer.

Diagnostic blood tests

These tests are designed to identify tumor caused impairment.

Blood tests like CBC’s- complete blood counts and differential blood cell counts.

Tumor markers – Tumor markers are substances either released by cancer cells into the blood or urine or substances created by the body in response to cancer cells. Tumor markers are used to evaluate how well a patient has responded to treatment and to check for tumor recurrence. Eg Alpha fetoprotein (AFP), carcinoeembryonic antigen (CEA), Prostate specific antigen (PSA) etc are used to indicate the presence of tumor.

Imaging Techniques

Imaging is the process of producing valuable pictures of body structures and organs. It is used to detect tumors and other abnormalities, to determine the extent of disease, and to evaluate the effectiveness of treatment. Imaging may also be used when performing biopsies and other surgical procedures.

It is recognised that some cancers can be prevented. Most mouth cancers can be prevented by not chewing tobacco and most lung and throat cancers can be prevented by not smoking. Certain cancers are produced by chemicals used in industry. If workers are protected against contact with such occupational factors, some cancers can be prevented.

A well balanced diet with less fat and more green leafy vegetables, citrus fruits, milk etc. can protect people. Above all, even though not all cancers are preventable, many deaths due to cancer can be prevented by early detection and proper treatment. A knowledge of the warning signals of cancer helps one to get an early diagnosis and a successful treatment.

Chemotherapy is given for the following reasons:

• Shrink tumors

• Slow cancer’s growth

• Keep the cancer from spreading

• Relieve diseases related symptoms

• Prolong survival

Chemotherapy is used to treat many different types of cancer. The type, location, and stage of the cancer as well as your general health will largely determine if chemotherapy is appropriate and which agents ought to be used.

Chemotherapy can be administered via several routes. The most common method is intravenously. Intravenously, or IV, means the drug is given by vein. Usually, a thin needle is inserted into a vein on the hand or lower arm at the onset of treatment session and is removed at the conclusion. Chemotherapy can also be delivered by IV through catheters, ports, and pumps. A catheter is a soft, thin, flexible tube that is placed in a large vein in the body. It remains in place as long as necessary. Sometimes the catheter is attached to a port, which is a small round plastic or metal disc. A central venous catheter is placed in a large vein, most commonly in your chest. A peripherally inserted central catheter (PICC) is inserted into a vein in your arm and threaded to the deeper, central vein. An intrathecal catheter delivers chemotherapy drugs directly into the spinal fluid.