Mucinous tumors of the ovary: interobserver diagnostic variability and utility of sectioning protocols.

Abstract

To determine the interobserver variability of the subclassification of ovarian mucinous tumors and the utility of different sectioning protocols. Six pathologists retrospectively reclassified 73 mucinous tumors (30 adenomas, 22 low malignant potential tumors, and 21 carcinomas). Using probabilities, the accuracy of limited sectioning protocols was compared with that of a one section per centimeter protocol. The mean kappa statistic was 0.56, indicating only good agreement. Although a limited sectioning protocol would result in misdiagnosing cases of stage IA carcinoma as a low malignant potential tumor, the overall prognosis of patients with low malignant potential tumors would not markedly change. The prognosis of a patient with a low malignant potential tumor using limited sectioning was within the prognostic range owing to interobserver variability alone. We conclude that extensive sectioning of ovarian mucinous tumors has limited benefit.