Cancer Health Channel

Feature Article

Cancer

Definition

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

Alternative Names

Carcinoma; Malignant tumor

Causes, 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. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too rapidly. 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 multiple causes of cancers, including:

  • Radiation
  • Sunlight
  • Tobacco
  • Certain viruses
  • Benzene
  • Certain poisonous mushrooms and aflatoxins (a poison produced by organisms that can grow on peanut plants)

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, and colon cancer. In women in the U.S., the three most frequently occurring cancers are breast cancer, lung cancer, and colon cancer.

Certain cancers are more common in particular geographic areas. For example, in Japan, there are many cases of gastric cancer, while in the U.S. this type of cancer is relatively rare.

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Breast cancer (8 images) Average Rating: (Doctor-Reviewed information)
Breast cancer is a cancer that starts in the tissues of the breast. There are two main types of breast cancer: Ductal carcinoma starts in the tubes (ducts) that move milk from the breast to the nipple. Most breast cancers are of this type; Lobular carcinoma starts in parts of the breast, called lobules, that produce milk. In rare cases, breast cancer can start in other areas of the breast. Many breast cancers are sensitive to the hormone estrogen. This means that estrogen causes the breast cancer tumor to grow. Such cancer is called estrogen receptor positive cancer or ER positive cancer. Some women have what's called HER2-positive breast cancer. HER2 refers to a gene that helps cells grow, divide, and repair themselves. When cells have too many copies of this gene, cells - including cancer cells - grow faster. Experts think that women with HER2-positive breast cancer have a more aggressive disease and a higher risk of recurrence than those who do not have this type. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided byVeriMed Healthcare Network.Date: 04/03/2007

Leukemia (9 images) (Doctor-Reviewed information)
Leukemia is a group of bone marrow diseases involving an uncontrolled increase in white blood cells (leukocytes. For information about a specific type of leukemia, see the following: Hairy cell leukemia; Chronic myelogenous leukemia (CML; Chronic lymphocytic leukemia (CLL; Acute lymphocytic leukemia (ALL; Acute myelogenous leukemia (AML. See also leukemia resources. Reviewer: Mark Levin, MD, Hematologist and Oncologist, Newark, NJ. Review provided by VeriMed Healthcare Network.Date: 03/09/2007

Lung cancer - small cell (18 images) (Doctor-Reviewed information)
Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It tends to spread much more quickly than non-small cell lung cancer. There are three different types of small cell lung cancer: Small cell carcinoma (oat cell cancer; Mixed small cell/large cell carcinoma; Combined small cell carcinoma. Most small cell lung cancers are the oat cell type. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 07/31/2006

Skin cancer (15 images) (Doctor-Reviewed information)
Skin cancer is the uncontrolled growth of abnormal skin cells. If left unchecked, these cancer cells can spread from the skin into other tissues and organs. There are different types of skin cancer. Basal cell carcinoma is the most common. Melanoma is less common, but more dangerous. Reviewer: Kevin Berman, MD, PhD, Associate, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 02/05/2008

Prostate cancer (5 images) Average Rating: (Doctor-Reviewed information)
Prostate cancer is cancer that grows in prostate gland. The prostate is a small, walnut-sized structure that makes up part of a man's reproductive system. It wraps around the urethra, the tube that carries urine out of the body. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Cervical cancer (5 images) (Doctor-Reviewed information)
Cervical cancer is cancer that starts in?the cervix,?the?lower part of the uterus (womb)?that opens at?the top of the vagina.? Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided byVeriMed Healthcare Network.Date: 06/09/2006

Endometrial cancer (7 images) (Doctor-Reviewed information)
Endometrial cancer is cancer that starts in the endometrium, the lining of the uterus (womb. Reviewer: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Susan Storck, MD, FACOG, Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine; Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. Date: 05/02/2008

Colon cancer (11 images) (Doctor-Reviewed information)
Colon cancer is cancer that starts in the large intestine (colon) or the rectum (end of the colon. Such cancer is sometimes referred to as "colorectal cancer." Other types of colon cancer such as lymphoma, carcinoid tumors, melanoma, and sarcomas are rare. In this article, use of the term "colon cancer" refers to colon carcinoma and not these rare types of colon cancer. Reviewer: Stephen Gund, MD, PhD, Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/24/2008

Bladder cancer (3 images) (Doctor-Reviewed information)
Bladder cancer is a malignant tumor within the bladder. In the United States, bladder cancers usually?start from the cells lining the bladder (transitional cells. These tumors may be classified based on their growth pattern: Papillary tumorshave a wart-like appearance and are attached to a stalk; Nonpapillary tumors are much less common, but they are more invasive and have a poorer prognosis. Reviewer: Stephen Grund, M.D. Ph.D., Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided by VeriMed Healthcare Network.Date: 12/14/2007

Ovarian cancer (8 images) (Doctor-Reviewed information)
Ovarian cancer is cancer that starts in the ovaries. The ovaries are the female reproductive organs that produce eggs. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Esophageal cancer (2 images) (Doctor-Reviewed information)
Esophageal cancer is a malignant (cancerous) tumor of the esophagus, the muscular tube that moves food from the mouth to the stomach. See also: Barrett's esophagus Reviewer: Mark Levin, MD, Hematologist and Oncologist, Newark, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 04/08/2008

Oral cancer (2 images) (Doctor-Reviewed information)
Oral cancer is cancer of?the mouth. Reviewer: Stephen Grund, MD, PhD, Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/21/2008

Pancreatic carcinoma (4 images) (Doctor-Reviewed information)
Pancreatic carcinoma is cancer of the pancreas. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Thyroid cancer (4 images) (Doctor-Reviewed information)
Thyroid cancer is a cancerous growth of the thyroid gland. Reviewer: Stephen Grund, MD, PhD, Chief of Hematology/Oncology and Director of the George Bray Cancer Center at New Britain General Hospital, New Britain, CT. Review provided byVeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 03/24/2008

Testicular cancer (2 images) (Doctor-Reviewed information)
Testicular cancer is an abnormal, rapid, and invasive growth of cancerous (malignant) cells in the testicles (male sex glands adjacent to the penis. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided byVeriMed Healthcare Network.Date: 05/26/2006

Gastric cancer (3 images) (Doctor-Reviewed information)
Gastric cancers are malignancies of the stomach. Reviewer: A.D.A.M. Editorial Team: David Zieve, MD, MHA, Greg Juhn, MTPW, David R. Eltz, Kelli A. Stacy, ELS. Previously reviewed by Rita Nanda, MD, Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network (9/11/2006).Date: 04/07/2008

Non-Hodgkin's lymphoma (2 images) (Doctor-Reviewed information)
Non-Hodgkin's lymphoma is cancer that starts in the lymphoid tissue. Such tissue makes up the lymph nodes, spleen, and other organs of the immune system. Reviewer: Corey Cutler, MD, MPH, FRCP(C), Assistant Professor of Medicine, Harvard Medical School; Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Hepatocellular carcinoma (3 images) (Doctor-Reviewed information)
Hepatocellular carcinoma is cancer of the liver. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Cancer - penis (2 images) (Doctor-Reviewed information)
Cancer of the penis is cancer that starts in the penis, an organ that makes up part of the male reproductive system. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 10/31/2006

Vaginal tumors (3 images) (Doctor-Reviewed information)
A vaginal tumor is an abnormal growth of tissue in the vagina, a female reproductive organ. Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 09/11/2006

Diet - cancer treatment (Doctor-Reviewed information)
People with cancer need special nutritional planning and management. Reviewer: Cynthia Dennison Haines, MD, family physician specializing in nutrition, fitness, and preventive health, St. John's Mercy Medical Center, St. Louis, MO, and Assistant Clinical Professor, St. Louis University's School of Medicine, Department of Community and Family Medicine.Date: 08/06/2007

Cancer - resources (Doctor-Reviewed information)
Resources - cancer The following organizations are good resources for information on cancer:American Cancer Society - www.cancer.orgNational Cancer Institute - www.cancer.govReviewer: A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy.Date: 10/11/2006

Cancer treatment information (Doctor-Reviewed information)
Cancer warning signs The goals of cancer treatment are to:Kill or remove cancer cellsPrevent or delay the cancer from coming backTreat cancer symptoms (if the cancer can not be cured)The types of treatment depend on the specific type of cancer, bu...Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare Network.Date: 10/31/2006

Cell phones - do they cause cancer? (Doctor-Reviewed information)
Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, there is no definitive answer at this time.The amount of time people spend on cell phones has ...Reviewer: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided byVeriMed Healthcare Network.Date: 09/25/2006

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