Factors associated with the inconsistent diagnosis between frozen section and permanent pathologic examination in borderline ovarian tumors.

AIM The predictive accuracy of frozen sections for borderline ovarian tumors (BOTs) is suboptimal. The aim of this study was to determine the diagnostic accuracy of BOTs and factors associated with an upgrade to a permanent pathological diagnosis of invasive carcinoma in patients diagnosed with BOTs by frozen section. METHODS We conducted a retrospective study between 2011 and 2018 at Kaohsiung Chang Gung Memorial Hospital (KCGMH). Two hundred and twenty-five records of eligible patients with a diagnosis of BOT by frozen section or permanent diagnosis were reviewed. Positive predictive value and the diagnostic accuracy of frozen sections were calculated. Univariate and multivariate analyses were used to determine the clinicopathological factors associated with an upgrade of the diagnosis from a borderline tumor to malignancy. RESULTS The agreement between frozen section and permanent pathological diagnoses was 63.1%, and the positive predictive value was 72.1%. The multivariate analysis revealed that CA-125 level > 136 U/mL (odds ratio [OR] = 2.96, 95% confidence interval [CI] = 1.3-6.9; p = 0.012), and tumor histologic type (clear cell/endometrioid vs. mucinous; OR:32.8, 95% CI = 6.9-154.8, p < 0.001; clear cell/endometrioid vs. serous: OR 48.1, 95% CI = 8.8-261.8, p < 0.001) were independent risk factors for an upgrade of the permanent diagnosis from a BOT to ovarian carcinoma. CONCLUSION An elevated CA-125 level (over 136 U/mL) and tumor histologic type (clear cell and endometrioid subtypes) were associated with an upgrade in the diagnosis of ovarian tumor from a BOT on frozen section to a permanent diagnosis of malignancy.