To the Editor.
—The study by Dr Modan and colleagues1 describes the high frequency of BRCA1 185delAG mutation in Israeli women with ovarian cancer. The patients in this study, 585 Israeli women with ovarian cancer, included 116 women (19.8%) with borderline ovarian tumor. None of the subjects with borderline tumor was found to be a carrier of this mutation. We believe that this difference between frankly invasive and borderline ovarian tumors should be evaluated further.Recently published evidence suggests that the differences between invasive and borderline ovarian tumors are not based on minor morphologic criteria, but that, most probably, these are 2 biologically different entities.2 No association was found in a recent Israeli study between borderline ovarian tumors and familial history of ovarian cancer,3 in contrast to strong positive association between familial history and invasive epithelial ovarian cancer.4 Further, in a preliminary study including 23 consecutive