Background: It is estimated that approximately 5-10% of epithelial ovarian cancer patients in Western countries are associated with an autosomal dominant inheritance with variable penetrance. There are a few reports of familial ovarian cancer in Japan and considerable uncertainties remain regarding Japanese familial ovarian cancer. The aim of this study was to clarify the clinicopathological features of Japanese familial ovarian cancer.
Methods: We studied clinicopathological findings for 219 consecutive epithelial ovarian cancer patients treated at our institution from April 1987 to September 1997.
Results: Eleven patients in nine families were diagnosed as familial ovarian cancer and the incidence of familial cases was 5.0%. Most women (90.9%) with familial cases were diagnosed as the breast ovarian cancer syndrome, whereas ovarian cancer associated with hereditary nonpolyposis colorectal cancer was relatively rare (9.1%). Serous adenocarcinoma, high histological grade, advanced FIGO stage and breast cancer as multiple primary cancer were significantly more common in familial cases compared with sporadic cases (p < 0.001, p < 0.05, p < 0.005 and p < 0.005, respectively). Earlier age of onset was thought to be a characteristic of familial ovarian cancer in Western countries; however, we did not find any difference in age at diagnosis between familial and sporadic cases (53.4 vs 51.3 years). The prognosis of familial ovarian cancer remains controversial and our data did not show a significant difference (p = 0.45) in prognosis between these two groups.
Conclusion: These findings, except for age at diagnosis, in Japanese familial ovarian cancer are in accordance with the features of familial ovarian cancer in Western countries.