Cancer

Definition

Cancer is a term used for diseases in which abnormal cells divide without control and are able to invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymph systems. Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for the organ or type of cell in which they start – for example, cancer that begins in the colon is called colon cancer; cancer that begins in basal cells of the skin is called basal cell carcinoma.

Cancer hits African Americans particularly hard. African American men are over twice as likely to die from prostate cancer than Whites. And while breast cancer is diagnosed 10% less frequently in African American women than White women, African American women are 40% more likely to die from the disease.

• In 2007, African American men were 1.3 times and 1.4 times, respectively, more likely to have new cases of lung and prostate cancer, as compared to non-Hispanic white men.
• African American men were almost twice as likely to have new cases of stomach cancer as non-Hispanic white men.
• African Americans men had lower 5-year cancer survival rates for lung, colon and pancreatic cancer, as compared to non-Hispanic white men.
• African American men are 2.5 times as likely to die from prostate cancer, as compared to non-Hispanic white men.
• In 2006, African American women were 10% less likely to have been diagnosed with breast cancer, however, they were almost 40% more likely to die from breast cancer, as compared to non-Hispanic white women.
• African American women are 2.1 times as likely to have been diagnosed with stomach cancer, and they are 2.4 times as likely to die from stomach cancer, as compared to non-Hispanic white women.

Cancer types can be grouped into broader categories. The main categories of cancer include:

• Carcinoma – cancer that begins in the skin or in tissues that line or cover internal organs.
• Sarcoma – cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.
• Leukemia – cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.
• Lymphoma and myeloma – cancers that begin in the cells of the immune system.
• Central nervous system cancers – cancers that begin in the tissues of the brain and spinal cord.

Alternative Names

Carcinoma; Malignant tumor

Causes

All cancers begin in cells, the body’s basic unit of life. To understand cancer, it’s helpful to know what happens when normal cells become cancer cells.

The body is made up of many types of cells. These cells grow and divide in a controlled way to produce more cells as they are needed to keep the body healthy. When cells become old or damaged, they die and are replaced with new cells.

However, sometimes this orderly process goes wrong. The genetic material (DNA) of a cell can become damaged or changed, producing mutations that affect normal cell growth and division. When this happens, cells do not die when they should and new cells form when the body does not need them. The extra cells may form a mass of tissue called a tumor.

Not all tumors are cancerous; tumors can be benign or malignant.

• Benign tumors aren’t cancerous. They can often be removed, and, in most cases, they do not come back. Cells in benign tumors do not spread to other parts of the body.
• Malignant tumors are cancerous. Cells in these tumors can invade nearby tissues and spread to other parts of the body. The spread of cancer from one part of the body to another is called metastasis.

Some cancers do not form tumors. For example, leukemia is a cancer of the bone marrow and blood.

Symptoms

Symptoms of cancer depend on the type and location of the cancer.

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 tests (which look for chemicals such as tumor markers)
• Bone marrow biopsy (for lymphoma or leukemia)
• Chest x-ray
• Complete blood count (CBC)
• CT scan
• MRI 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.

Treatments

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 to one 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. Some cancers require a combination of surgery, radiation, and chemotherapy.
• Lymphoma, or cancer of the lymph glands, is rarely treated with surgery. Chemotherapy and radiation therapy are most often used to treat lymphoma.

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.

Possible Complications

One complication is that the cancer may spread. Other complications vary with the type and stage of the tumor.

When to Contact a Medical Professional

Contact your health care provider if you develop symptoms of cancer.

Preventions

Cancer prevention is action taken to lower the chance of getting cancer. By preventing cancer, the number of new cases of cancer in a group or population is lowered. Hopefully, this will lower the number of deaths caused by cancer.

Cancer is not a single disease but a group of related diseases. Many things in our genes, our lifestyle, and the environment around us may increase or decrease our risk of getting cancer.

Scientists are studying many different ways to help prevent cancer, including the following:

• Ways to avoid or control things known to cause cancer.
• Changes in diet and lifestyle.
• Finding precancerous conditions early. Precancerous conditions are conditions that may become cancer.
• Chemoprevention (medicines to treat a precancerous condition or to keep cancer from starting).

You can reduce the risk of getting a cancerous (malignant) tumor by:

• Eating a healthy diet
• Exercising regularly
• Limiting alcohol
• Maintaining a healthy weight
• Minimizing your exposure to radiation and toxic chemicals
• Not smoking or chewing tobacco
• Reducing sun exposure, especially if you burn easily

Cancer screenings, such as mammography and breast examination for breast cancer and colonoscopy for colon cancer, may help catch these cancers at their early stages when they are most treatable. Some people at high risk for developing certain cancers can take medication to reduce their risk.