Type Stomach Cancer

Type Stomach Cancer

About 21,500 Americans and 2,800 Canadians are diagnosed with cancer of the stomach each year. Stomach cancer is about twice as common in men as it is in women, and it occurs much more frequently in people who have experienced long-term infection with the Helicobacter pylori bacterium. Incidence of stomach cancer varies significantly between different populations. In Japan, for example, the disease is five times more common than it is in the United States. Researchers attribute these regional risk differences to dietary differences. Diets high in smoked or cured meats appear to increase the risk of stomach cancer. In the United States, stomach cancer is now only one-fourth as common as it was in 1930. This decline may be due, in part, to the increased use of refrigeration for food storage and decreased use of salted and smoked foods.

Approximately 90 to 95 percent of all cancers of the stomach are adenocarcinomas that develop in the lining of the stomach. Cancers of the immune tissue in the stomach wall, called gastric lymphomas, make up about 4 percent of all cancers of the stomach. Gastric sarcomas develop in the muscle tissue in the stomach wall, and account for only about 3 percent of all stomach cancers.

Like many cancers of the internal organs, stomach cancer rarely produces noticeable symptoms until it has spread to other sites in the body. When symptoms are present, they may include abdominal pain, heartburn, nausea, and vomiting. Stomach cancer is rarely detected early, and only about 20 percent of people diagnosed with stomach cancer in the United States live five years or longer.

Contributed By:Karen R. Peterson

Type Ovarian Cancer

Type Ovarian Cancer

About 23,100 cases of ovarian cancer in American women and 2,500 cases in Canadian women are diagnosed annually. Women over the age of 50 have a higher risk for ovarian cancer, as do women who have had breast cancer. Other conditions that increase the risk for ovarian cancer include early age at first menstruation, late menopause, having a first child after age 30, or having no children at all. Women with a close relative who has ovarian cancer are also at greater risk, as are women with inherited mutations in the tumor suppressor genes BRCA1 and BRCA2.
The ovaries, two almond-shaped glands on either side of the uterus, produce eggs and release hormones that regulate menstruation and pregnancy. Malignant ovarian tumors arise in the epithelial tissue of the ovaries, in the connective tissue, or in the germ cells—the egg-producing cells. Ovarian carcinomas, those that arise in the epithelial tissue, account for 85 to 90 percent of all ovarian cancer. Sarcomas account for less than 5 percent of all cases, and several different types of germ cell cancers account for the remaining 5 to 10 percent of ovarian cancers.
Ovarian cancer accounts for just under 5 percent of all cancer in women. While rare, it often does not produce symptoms and goes undiagnosed until the cancer has spread and become more deadly. At that point, a woman may experience any of a variety of symptoms, such as an enlarged abdomen, persistent abdominal discomfort, indigestion, nausea or vomiting, weight loss, diarrhea or constipation, and bleeding that is not part of a normal menstrual period. If diagnosed and treated before the cancer has spread, the five-year survival rate in the United States is 95 percent, but only about 25 percent of ovarian cancers are detected this early. Overall, the five-year survival rate is 50 percent. Contributed By:Karen R. Peterson