HolaCauses, incidence, and risk factors
Cells are the building blocks of living things.
Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells forget how to die.
There aremany different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.
There are many causes of cancers, including:
•Benzene and other chemicals
•Drinking excess alcohol
•Environmental toxins, such as certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
However, the cause of many cancers remains unknown.
The most common cause of cancer-related death is lung cancer.
The three most common cancers in men in the United States are:
In women in the United States, the three most common cancers are:
•Breast cancer•Colon cancer
Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of stomach cancer, but in the United States, this type of cancer is pretty rare. Differences in diet may play a role.
Some other types of cancers include:
•Liver cancer•Non-Hodgkin's lymphoma
Symptoms of cancer depend on the type and location of the cancer. For example, lung cancer can cause coughing, shortness of breath, or chest pain. Colon cancer often causes diarrhea, constipation, and blood in the stool.
Some cancers may not have any symptoms atall. In certain cancers, such as pancreatic cancer, symptoms often do not start until the disease has reached an advanced stage.
The following symptoms can occur with most cancers:
•Loss of appetite
Signs and tests
Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common testsinclude the following:
•Biopsy of the tumor
•Blood tests (which look for chemicals such as tumor markers)
•Bone marrow biopsy (for lymphoma or leukemia)
•Complete blood count (CBC)
Most cancers are diagnosed by biopsy. Depending on the location of the tumor, the biopsy may be a simple procedure or a serious operation. Most patients withcancer have CT scans to determine the exact location and size of the tumor or tumors.
A cancer diagnosis is difficult to cope with. It is important, however, that you discuss the type, size, and location of the cancer with your doctor when you are diagnosed. You also will want to ask about treatment options, along with their benefits and risks.
It's a good idea to have someone with you at thedoctor's office to help you get through the diagnosis. If you have trouble asking questions after hearing about your diagnosis, the person you bring with you can ask them for you.
Treatment varies based on the type of cancer and its stage. The stage of a cancer refers to how much it has grown and whether the tumor has spread from its original location.
•If the cancer is confined toone location and has not spread, the most common treatment approach is surgery to cure the cancer. This is often the case with skin cancers, as well as cancers of the lung, breast, and colon.
•If the tumor has spread to local lymph nodes only, sometimes these can be removed.
•If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both....
Leer documento completo
Regístrate para leer el documento completo.