Cancer is the second leading cause of death. Cancer is not one disease but many disorders with widely different natural histories and responses to treatments. Some cancers, such as Hodgkin lymphoma, are curable, whereas others, such as pancreatic adenocarcinoma, are virtually always fatal.
Cancer is also known as neoplasia. Neoplasia means “new growth” and a new growth is called neoplasm. Tumor is the swelling caused by inflammation, but the nowadays the term equated with neoplasm.

There are 3 types of tumors :

1.Benign tumor
2.Malignant tumor
3.Mixed tumor

Benign tumor

A tumor is said to be benign when its gross and microscopic appearances are considered relatively innocent, implying that it will remain localised, will not spread to other sites, and is amenable to local surgical removal; understandably, the patient generally survives. However benign tumors may cause significant morbidity and are sometimes even fatal.

Malignant tumor

Malignant tumors are collectively referred to as cancers, derived from Latin word for crab, in an obstinate manner. Malignant tumors can enter and destroy adjacent structures and spread to distant sites (metastasize) which can cause death. Some are discovered early enough by the medical oncologist and they suggest treatments to be excised surgically or are treated successfully with chemotherapy or radiation, but the designation malignant always raises a red flag.

Factors causing cancer

1.Environmental factors

Among the best established environmental factors affecting cancer risk are following :
1. Infectious agents- Cancer is caused directly or indirectly by infectious agents, with the burden of cancers linked to infections being roughly 3 times higher in the developing world than developed world.
2. Smoking – Cigarette smoking has been called the single most important environmental factor contributing to premature death. Smoking, particularly of cigarettes, has been implicated in cancer of the mouth, pharynx, larynx, oesophagus, pancreas, bladder, and most significantly, about 90% of lung cancer deaths.
3. Alcohol consumption – Alcohol abuse alone increases risk of carcinomas of the oropharynx, larynx, and oesophagus and, by the development of alcoholic cirrhosis, hepatocellular carcinoma.
4. Diet – Although the precise dietary factors that affect cancer risk remain a matter of debate, wide geographic variation in the incidences of colorectal carcinoma, prostate carcinoma, and breast carcinoma has been ascribed to differences in diet.
5. Obesity – Approximately 14% of cancer deaths in men and 20% in women can be attributed to obesity.
6. Environmental carcinogens – They lurk in the ambient environment, in the workplace, in food, and in personal practices. Individuals may be exposed to carcinogenic factors when they go outside (e.g., UV rays, smog), drink well water (e.g., arsenic), take certain medications (e.g., methotrexate), go to work (e.g., asbestos), or even while lounging at home (e.g., grilled meat, high fat diet, alcohol).

2.Age

Age has an important influence on the likelihood of being affected by cancer. Most carcinomas occur in the later years of life (>55years). Cancer is the main cause of death among women aged 40-79 and among men aged 60 to 70; the decline in deaths after the age of 80 is due to the lower number of individuals who reach this age.

3.Acquired Predisposing Conditions

Acquired conditions that predispose to cancer can be divided into chronic inflammation, precursor lesions, and immunodeficiency states.

Grading and staging of cancers

Grading – determined by cytologic appearance ; based on the idea that behaviour and differentiation are related, with poorly differentiated tumors having more aggressive behaviour.

Staging – determined by surgical exploration or imaging, is based on size, local and regional lymph node spread, and distant metastases; of greater clinical value than grading.

Diagnosis of cancer

Several sampling approaches exist for the diagnosis of tumors, including excision, biopsy, fine – needle aspiration, and cytologic smears. Cancer is ubiquitous in human population ; the only certain way to avoid the cancer is to not be born, as to live is to incur risk. You can consult the team of well known oncologist as Jaslok Hospital and Research Centre, Mumbai.

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