The human body is built up by combination of several cells like epithelial cells, connective tissue cell and muscular tissues. The balanced growth of these cells converts the newborn baby to a child: and a child to an adult. The coordinated efforts of the various organs of the body make the person a productive and social individual.

The unbalanced growth of the cells produces a swelling or a tumor. The tumors are unwanted growth of the cells. The tumors, which are swelling localized to the cells of its origin and does not spread to the different parts of the body are called benign tumors. These tumors could obstruct the passage or produce disfigurement. Some of these benign tumors may turn into malignant. The malignant tumors grow rapidly, spreads to the various part of the body and destroy the function of the system or the body and will invariably kill the individual. Because of its rapidly spreading nature, it is called malignant tumor. Those arising from epithelial cells are called carcinoma those arising from connective tissues are called sarcoma or from muscles are called rhabdomyo sarcoma and from blood forming tissues are called Leukemia or lymph tissues are known Hodgkirss diseases.

Causes of Cancer
We have not been able to pinpoint the causes of cancer; but the following factors have been blamed as carcinogens (the factor responsible for producing cancer). For example the use of tobacco products is responsible for more incidence of cancer of the lungs (cigarettes, bidis, sulpha, hookka smoking). Similarly people using tobacco (chewing tobacco) are more prone to carcinoma of the oral cavity and throat. Similarly people eating smoked meat are more prone to gastric carcinoma etc.
Some cancer runs in the family: hence it may due to some unknown heredity factors. Similarly, some cancer is produced following infection by virus infection- e.g. human papilloma virus, hepatitis B virus or HIV virus. The people exposed to asbestos, arsenic, radiation and ultraviolet light are more prone to develop cancer.

IS CANCER A HEREDITARY DISEASE?
Some of the cancers are hereditary: e.g. the retinoblastoma, breast cancer, gastric cancer and rectal carcinoma could also be hereditary (it may be due to exposure to similar environment).
How does cancer spread?
It must be very clear that cancer is not infective (doesn't spread from one person to another). It spreads by:
I . Direct invasion into the surrounding tissues: e.g. the breast cancer can spread to the muscles, ribs and pleural cavity.
2. Lymphatic: the cancer cells usually spread through lymph channels draining the area. These cells get obstructed at the lymph nodes; but later on spread further and pass into the veins draining the area. The lymph nodes are freely mobile in the early stage but later on) get fixed (due to infiltration into the surrounding tissue).
3. Blood: the tumor cells drains into the veins and then spreads to the various organs in the body. For example tumor arising in the breast, thyroid can spread to the liver, lungs, brain and bones.
4, Transcoelomic spread: the tumor cells could also spread through various bodily cavities: e.g. peritoneum, pleura, synovial cavity and produces metastasis in the various organs e.g. the cancer of the breast spreading to the ovaries in menstruating ladies KRUCKENBURG'S TUMOR).

What are the features of cancer?
The early features of the cancer could be the following:
I . Development of painless lump or thickening in any parts of the body- goes on increasing in size.
2. Alteration in bowel habit or urination in adults or elderly people.
3 Ulcer that doesn't heal up with time.
4. Irregular bleeding from natural passage, e.g. mouth, nose, rectum, urethra, vegina etc.
5. Difficulty in swallowing.
6. Change in the shape and size of wart or mote: ulceration.
7. Unexpected loss of weight,
Every individual should be concerned about these features
abnormal tissue and send for histopathological examination.
d. Excisional biopsy- Examination of diseased organs after removal. This includes the tumor, surrounding tissues and the draining lymph nodes.

Treatment of Cancer
IF DEFECTED EARLY AND TREATED PROPERLY, THE CANCER COULD BE CURED. Hence, the result of cancer treatment depends on the person. Every individual must be observant on his system and should not ignore any change. The methods available for treating cancers are:
I . Surgery: the diseases organ and the possible site of spread are excised. During operation the margins are examined to see the adequacy of the resected margins. The defect caused by surgery could be covered by plastic surgical procedures.
2. Radiotherapy: the radiation (both external and internal) destroys the rapidly dividing cancer cells and not the normal cells and helps to protect the organ. The radiation is used as supplementary to surgical procedures or as palliative procedures.
3. Chemotherapy: some of the tumor cells are destroyed by chemotherapeutic agents by affecting the rapidly dividing cells. It could also affect the normal cells of the body but doesn't destroy them.
4. Hormone therapy: some tumors are dependent on hormones for its development. Hence, their use could prevent them from growing.