The accuracy of frozen section by tumor weight for ovarian epithelial neoplasms

This study evaluated the effect ovarian weight has on the accuracy of frozen sections in serous and mucinous ovarian tumors. The study group included 294 patients who had an initial frozen section (189 serous and 105 mucinous tumors) at surgery, The pathology reports were separated into subgroups (benign, borderline, or malignant), Tumors were broken down into three weight categories: less than or equal to 450 g, >450 to less than or equal to 1360 g, and >1360 g. In each weight category, accuracy, sensitivity, specificity, and positive and negative predicative values were calculated on frozen sections. The mean weight of the ovarian tumors was 1042 g. As the weight increased in serous tumors, the sensitivity fell from 96.2 to 93.8 to 75%, respectively, in each weight category. The same trend was noted with mucinous tumors as sensitivity fell from 91.7 to 87.5 to 66.7%, respectively, With an increase in the size of ovarian tumors, a decrease in the sensitivity of frozen section was observed. With tumors greater than 1360 g, sensitivity was only 69%. Twenty-three percent of ovarian tumors revealing borderline diagnosis at frozen section were malignant on the final pathology report, with the greatest misclassification in >1360-g mucinous tumors (50%), For patients with large ovarian tumors, consideration should be given to performing staging at the time of the initial laparotomy. (C) 1997 Academic Press.