Ovarian Cancer

OVARIAN CANCER
INCIDENCE AND EPIDEMIOLOGY
Ovarian cancer can develop from three distinctive cell types (germ cells, stromal cells, and epithelial cells). Epithelial ovarian cancer is the mostcommon. The age-specific incidence of the common epithelial type of ovarian cancer increases progressively and peaks in the eighth decade. Epithelial tumors, unlike germ cell and stromal tumors, areuncommon before the age of 40. There is an increased risk for those who have been exposed to asbestos or talc; in industrialized nations; and in women with disordered ovarian function, includinginfertility, nulliparity, and frequent miscarriages. Reduction in ovarian cancer risk is associated with pregnancy (each pregnancy reduces the ovarian cancer risk by about 10%), breast-feeding, and tuballigation.
Two types of autosomal dominant familial cancers have been identified: (1) breast/ovarian cancer syndrome; and (2) the Lynch type II cancer family syndrome with nonpolyposis colorectal cancer,endometrial cancer, and ovarian cancer.

ETIOLOGY AND GENETICS
In women with hereditary breast/ovarian cancer, two susceptibility loci have been identified: BRCA1, located on chromosome 17q12-21, andBRCA2, on 13q12-13. The Lynch type II syndrome is associated with an increased risk of ovarian cancer.

CLINICAL PRESENTATION AND DIFFERENTIAL DIAGNOSIS
70% of patients with ovarian cancer arefirst diagnosed when the disease has already spread beyond the true pelvis. The occurrence of abdominal pain, bloating, and urinary symptoms usually indicates advanced disease, progressive enlargement ofa localized ovarian tumor can produce urinary frequency or constipation, vaginal bleeding or discharge is rarely seen with early ovarian cancer. The diagnosis of early disease usually occurs withpalpation of an asymptomatic adnexal mass during routine pelvic examination or as an incidental finding at surgery. However, most ovarian enlargements discovered on physical examination, especially in...