In 1995, an estimated 26,600 women in the United States will be diagnosed with ovarian cancer. During that same year, approximately 14,500 women will die from the disease. Although ovarian cancer accounts for only 33% of the gynecologic cancers and only 5% of all cancers affecting women in the United States, it results in 55% of the deaths from gynecologic cancer and 6% of the cancer deaths in women. The cure rate for ovarian cancer by stage at diagnosis is not significantly different from other gynecologic cancers. Ovarian cancer confined to the ovary (Stage I) can be cured in 90% of cases. Survival for patients with advanced disease (Stages I11 and IV) is 21%.
Unfortunately, while 73% of endometrial cancers, 55% of breast cancers, and 50% of cervical cancers are diagnosed as Stage I, only 23% of ovarian cancers are diagnosed as Stage I. Thus, five-year survival for all endometrial cancer is 85%, for all breast cancer, 82%, for cervical cancer, 70%, and for ovarian cancer, only 42%. The lack of early symptoms and the absence of any proven method of screening for early ovarian cancer results in over 70% of women being diagnosed after the disease has spread beyond the ovary. Also, unlike breast, cervical, and endometrial cancer, there is no known premalignant phase for ovarian cancer; therefore, diagnosis and treatment of a premalignant condition to prevent the development of ovarian cancer is not possible. Theories to explain the development of ovarian cancer are based on observations that ovulation inhibition through pregnancy, oral contraceptive use, and a shorter ovulatory period (late menarche or early menopause) result in a decreased incidence of ovarian cancer. The incessant disruption of the ovarian capsule followed by repair may provide the opportunity for aberrant growth. Finally, therapy of women with ovarian cancer usually requires multiple surgical procedures, multiple courses of chemotherapy, and results in significant morbidity and health care costs. For most women with the disease, the end result will still be a slow, painful death by starvation. There should be little doubt based on the above statistics that every effort should be directed towards prevention of ovarian cancer. Possible strategies in the prevention of ovarian cancer should be directed towards determining if a premalignant condition exists, developing screening tools to detect premalignant disease or disease confined to the ovary, and developing interventions to prevent the development of the disease. It is well established that use of oral contraceptives for five or more years can result in up to a 50% reduction in the occurrence of epithelial ovarian cancer. Given the low complication rates from oral contraceptive use, this medication should be considered as a method of prevention, especially in high-risk groups. In addition, this is a realistic starting point for research into the development of preventive regimens.