The total population-based material of 426 ovarian malignancies in the Southeast Health Care Region of Sweden during 1984-1987 was surveyed. It seems that with a program of cytoreductive surgery followed by a cisplatinum chemotherapy combination in the metastasizing cases the overall survival figures have improved. A relative overall 5-year survival of 43% was recorded. Age and stage were independent prognostic factors for survival, while histology (epithelial vs, non-epithelial tumors) did not add prognostic information.384 patients with ovarian carcinomas were analyzcd separately. An overall relative survival of 40% was recorded. Tite overall corrected 5-yearsurvival for patients prescribed protocol treatment was 49 % compared to 33 % for those treated otlJCrwise. The corrected 5-year survival for patients with FIGO stage Ill -IV tumorswas 35 % if optimal primary cy~oreductive surgery wasperfonned.Patientswith residual tumors greater than 1cm had 13% corrected5-yearsurvival. Patients that underwent intestinal surgery as a part of initial surgical debulking had a very poor survival, even compared with 1l1e group of patients with greater than 3 cm residual tumors left after initial surgery ( 4 vs. 13 %). The secondary laparotomy gave prognostic information only in stages I and ll. Eighteen of 68 patients (26 %) who had macroscopic turn or left at the secondary surgery cmdd be rendered tumor free at the secondary laparotomy. This group had about the same survival as those who were foi.Uld to be in complete response at the secondary laparotomy. It was not possible to ~iatc that this was caused by the ~urgeryper se.Geometrical measurements oftumor nuclei on the diagnostic tissue sections generated powerful prognostic factors for survival after secondary laparotomy in 65 patients with advanced ovarian cancer. The existence of very large nuclei seemed to cl1aracterize patients with a bad prognosis.The half-life of the turn or marker CA 125 in serum during induction chemothrapy gave equally good prognostic information regarding the survival after secondary laparotomy in 72 patients with advanced ovarian cancer as registering the response to therapy at the secondary laparotomy.In 33 ovarian cancer patients monitoring with monthlyscrum CA 125 determinations during follow-up was a reliable method to diagnose a recurrence with very few (0.9%) false positive values.