Ovarian cancer is the ninth most common cancer in women, but is the fifth most common cause of cancer deaths in women in the United States. It is the most common cause of gynecologic cancer death. The American Cancer Society estimates that about 21,880 women will be diagnosed with ovarian cancer in 2011, and over 13,850 women will die of ovarian cancer this year. The lifetime risk of developing ovarian cancer is 1 in 70 for women at average risk. The average age at diagnosis is 63. Caucasian women have the highest incidence. Most women (about 70%) are diagnosed with advanced stage ovarian cancer (stage 3 or 4). When ovarian cancer is found early (stage I), the five-year survival is greater than 90%.
There are three main types of ovarian cancer: epithelial, germ cell, and sex-cord stromal tumors. Epithelial ovarian cancer is the most common, accounting for about 90% of all ovarian cancer. In this article, I will focus on epithelial ovarian cancer.
Risk Factors and Genetic Predisposition
Risk factors for ovarian cancer include early age at menarche (when menses start, before age 12), late menopause (after age 50), never being pregnant, infertility, endometriosis and polycystic ovarian syndrome. Family history of breast or ovarian cancer is also a risk, and about 10% of all ovarian cancer is hereditary.
There are two main inherited genetic predispositions for ovarian cancer: a BRCA 1 or 2 mutation and hereditary nonpolyposis colorectal cancer (HNPCC). Women with a BRCA 1 mutation have a 20 to 45% lifetime chance of developing ovarian cancer, while women with a BRCA2 mutation have a 10 to 20% lifetime chance. Women with a BRCA mutation are also at increased risk of developing breast cancer. Women with HNPCC have a 9 to 12% lifetime risk of developing ovarian cancer. Other cancers associated with HNPCC include colon cancer, uterine cancer, stomach cancer, small bowel cancer and kidney cancer. Any woman diagnosed with ovarian cancer should consider seeing a genetics counselor for BRCA testing.