Objective: The aim of this register study was to determine occurrence of non-genital ovarian metastasis detected by gynecologic surgery presented as ovarian neoplasm in Sweden from 1 January 1990 to 31 December 2003. Origin of metastases and time of detection in relation to surgery were recorded. Age at diagnosis, survival for ovarian metastasis compared to ovarian cancer and prognostic factors were evaluated.
Methods: Utilizing the population-based Swedish In-Patient Registry, Cancer Registry and Causes of Death Registry, we identified 255 cases with non-genital tract metastases to the ovaries detected at gynecological surgery. During the study period, 10,955 newly diagnosed cases of ovarian cancer were reported to the Swedish Cancer Registry.
Results: The proportion of ovarian metastases detected at surgery of all ovarian neoplasm increased from 1.7% to 3.0% during the study period. The patients with ovarian metastasis of non-GI origin were younger than patients with primary ovarian cancer. The most common primary diseases were breast cancer (29%), colon cancer (27%) and gastric cancer (16%). Ovarian metastasis of GI origin preceded primary diagnosis in 51% of patients but for women with disease of non-GI origin the primary diagnosis was made in 18% of patients after surgery. Five-year survival for patients with ovarian metastasis of GI origin was 11% and it was 24% if metastases were of non-GI origin. Five-year survival for women with ovarian metastases from breast cancer was 26%. In a multivariate analysis, GI surgery at primary surgery for ovarian metastasis was unfavorable prognostic factor. Diagnosis of primary disease known before surgery, primary disease of non-GI or unknown origin and operation at university hospital all had favorable prognostic impact for overall survival.
Conclusions: Detection of non-genital ovarian metastasis at gynecologic surgery is associated with poor prognosis, and prognosis is worse in tumors with GI origin and if the primary is not detected prior to surgery. The results indicate that a thorough patient evaluation is very important before surgery for suspected ovarian neoplasm.