Cancer - all about cancer

Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.

Alternative Names
Carcinoma; Malignant tumor

Causes
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 are many 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
Certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
Certain viruses
Radiation
Sunlight
Tobacco

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:
Prostate cancer
Lung cancer
Colon cancer

In women in the U.S., the three most common cancers are:
Breast cancer
Colon cancer
Lung cancer

Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of gastric cancer, but in the U.S. this type of cancer is pretty rare. Differences in diet may play a role.

Some other types of cancers include:
Brain cancer
Cervical cancer
Hodgkin's lymphoma
Kidney cancer
Leukemia
Liver cancer
Non-Hodgkin's lymphoma
Ovarian cancer
Skin cancer
Testicular cancer
Thyroid cancer
Uterine cancer

Symptoms
Symptoms of cancer depend on the type and location of the tumor. 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 at all. In certain cancers, such as gallbladder cancer, symptoms often do not start until the disease has reached an advanced stage.

The following symptoms can occur with most cancers:
Chills
Fatigue
Fever
Loss of appetite
Malaise
Night sweats
Weight loss

Exams and Tests
Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common tests include the following:
Biopsy of the tumor
Blood chemistries
Bone marrow biopsy (for lymphoma or leukemia)
Chest x-ray
Complete blood count (CBC)
CT scan

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 with cancer 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 the doctor'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
Treatment also 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 to one location and has not spread, the most common goals for treatment are surgery and cure. 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 also be removed.
If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both. Some cancers require a combination of surgery, radiation, and chemotherapy.

Although treatment for cancer can be difficult, there are many ways to keep up your strength.

If you have radiation treatment, know that:
Radiation treatment is painless.
Treatment is usually scheduled every weekday.
You should allow 30 minutes for each treatment session, although the treatment itself usually takes only a few minutes.
You should get plenty of rest and eat a well-balanced diet during the course of your radiation therapy.
Skin in the treated area may become sensitive and easily irritated.
Side effects of radiation treatment are usually temporary. They vary depending on the area of the body that is being treated.

If you are going through chemotherapy, you should eat right. Chemotherapy causes your immune system to weaken, so you should avoid people with colds or the flu. You should also get plenty of rest, and don't feel as though you have to accomplish tasks all at once.

It will help you to talk with family, friends, or a support group about your feelings. Work with your health care providers throughout your treatment. Helping yourself can make you feel more in control.