Ovarian Cancer Controversy: When and How To Use Available Screening Methods

Ovarian cancer is the fourth most common cause of cancer death in American women. While the prognosis is excellent when the cancer is confined to the ovary, the majority of women are diagnosed after the tumor has spread to the upper abdomen, and their prognosis is poor. To diagnose the disease before it has spread, numerous studies have evaluated various methods of ovarian cancer screening. For example, such cytologic screens as cervical Papanicolaou smears and culdocentesis for cytologic analysis of cul-de-sac fluid have been studied, but they have been shown to be ineffective. Serum markers like CA-125 have proved useful in monitoring the progression of ovarian cancer after diagnosis, but the long list of other conditions that can elevate CA-125 hamper its usefulness in screening. Additional serum markers under current investigation include OVX-1, M-CSF, CA-15-3, CA-19-9, and TAG-72.3. Many investigators are studying imaging techniques such as transvaginal sonography (TVS). To distinguish between benign and malignant tumors seen in visualization studies, adjuncts such as color flow Doppler imaging to assess blood flow through a tumor, and tumor morphology indices that assign values to sonographic variables (eg, ovarian volume or cyst wall thickness) are also under study. The National Cancer Institute is currently performing a multicenter, randomized screening trial for ovarian cancer using the combination of serum CA-125 and TVS. However, until the results of this trial become available, the combined use of serum CA-125 and TVS cannot be recommended for ovarian cancer screening in the general population; these tests should be limited to clinical research settings and to those patients with a documented family history of ovarian cancer.