Cancer is a malignant tumor caused by the multiplication of abnormal cells in the human body. The cancerous cells may spread out from the tumor to the blood vessels, forming more tumours; this process is called metastasis.
Breast cancer most commonly affects women whose mother have had this kind of cancer, or women without children. The breast cancer may be discovered by physical palpation of the breast, or by mammography, a breast X-ray that detects the tumor before it can be felt. The treatment for breast cancer starts with a surgery: the excision or ablation of the tumor (tumorectomy), of the entire breast (radical mastectomy) or of the lymphectomy. Afterwards, the patient has to undergo radiotherapy, or chemotheraphy to destroy the remaining cancerous cells.
The most common skin cancers, such as epithelioma, are easier to detect and cure. However, the malignant melanoma is often fatal because its metastasis develops extremely fast. Change in the size or shape of a mole can indicate cancer.
The symptoms of prostate cancer are similar to those of adenoma: strong pains and difficulty to urinate. Prostate cancer affects men above 60 years old. This type of cancer may require surgery in order to remove the prostate. Afterwards, the patient undergoes chemotherapy.
Ovarian cancer is difficult to detect because its symptoms are felt after the tumor is in an advanced stage. In most cases, the ovarian cancer is benign, although its symptoms are similar to the malignant tumor. To remove the tumor, it is necessary to remove the womb, the fallopian tubes and the ovaries. After the surgery, the patient needs chemotherapy or radiotherapy.
Brain cancer may cause severe tranformations such as a disorder in the person's behavior and coordination, blindness and muscle weakness. Like any other kind of cancer, the brain cancer must be removed through surgery and radiotherapy. The brain cancer also affects children. It is the cause of the 28% of deaths by cancer before 15 years old.
Tobacco and air pollution are the main causes of a lung cancer. Although this kind of cancer is difficult to operate, it can be removed by pneumonectomy (the excision of the lung) or lobectomy (the excision of a pulmonary lobe). Chemotherapy is used in cases in which the tumor cannot be operated.
The leukemia appears when the blood contains more white cells than normal. Depending on the type of blood cell the leukemia varies. The different kinds of leukemia are monocytic, lymphoid, myeloid, acute (affects children), and chronic (affects adults above 50 years old). Leukemia can be diagnosed through a bone marrow examination.