Long-term follow-up of the Stockholm screening study on ovarian cancer

Objectives. Seventy percent of ovarian cancer is diagnosed at advanced stag es. Having a method for early diagnosis is a very attractive concept. Sever al attempts have been made, using monoclonal antibody-based immunoassays, u ltrasound, or combinations of both, to identify methods that might prove to be sufficiently sensitive and specific as a screening test. Despite promis ing results, a mortality study of a large population has yet to be complete d due in part to the high cost involved. Methods. One of the first studies aimed at devising a screening strategy fo r ovarian cancer used the CA 125 immunoassay followed by ultrasound. The st udy was performed in Stockholm from 1986 through 1988. Ten years now having passed, an analysis has been performed to further evaluate the results of that study. Results, Screening led to the diagnosis of ovarian cancer in six patients, five of whom have since died of the disease. By searching the Cancer Regist ry, we were able to identify 20 ovarian cancer patients who developed the d isease after the screening period. Of these, 12 died of the disease, 2 are alive with disease, and 6 have no evidence of disease following treatment. The median .survival for patients diagnosed by screening was 100 months. Me dian survival for ovarian cancer patients identified subsequent to screenin g was 20 months. Although there was no difference in survival between these two groups, median survival was better for women diagnosed by screening (b orderline significance, P = 0.059). Conclusion. These results indicate that a study of a large number of women with a sufficiently long observation time will be required to establish whe ther or not screening can reduce ovarian cancer mortality. Such a study may also provide insight into the natural history of ovarian cancer. (C) 2000 Academic Press.