Cancer is a class of diseases characterized by out-of-control cell growth. Normally cells grow and divide to form new cells. Normal cells grow old and die and new cells take their place.Sometimes this process goes wrong, New cells form when body does not need them and old cells do not die as they should. This buildup of extra cells is often forms a mass of tissue called growth or tumor. Changes to the DNA of the cell leads to damage and makes them cancerous.This may invade into other parts of the body interfering with normal body functions.
Not all tumors are cancerous, tumors which stay at one part and do not invade are called benign tumors. More dangerous or malignant tumors are formed by invasion, a cancerous cell moving through out the body using blood or lymph systems or angiogenesis, cells grow and divide making new blood vessels feed itself. When a tumor successfully spreads to other parts of the body and grows, invading and destroying other healthy tissues, it is said to have metastasized. This process itself is called metastasis, and the result is a serious condition that is very difficult to treat.
There are over 100 different known cancers that affect humans.Many cancers can be prevented by not smoking, eating more vegetables, fruits and whole grains, eating less meat and refined carbohydrates, maintaining a healthy weight, exercising, minimizing sunlight exposure, and being vaccinated against certain infectious diseases.
Cancer symptoms are quite varied and depend on where the cancer is located, where it has spread, and how big the tumor is. Possible signs and symptoms include: a new lump, abnormal bleeding, a prolonged cough, unexplained weight loss, and a change in bowel movements, among others. While these symptoms may indicate cancer they may also occur due to other issues. Early detection of cancer can greatly helps us for successful treatment and survival.