Usefulness of intraoperative imprint cytology in ovarian germ cell tumors.

Objective: This study retrospectively investigated the usefulness of intraoperative diagnosis based on imprint cytology and frozen sections for ovarian germ cell tumor. Study Design: Intraoperative studies were reviewed for 23 cases with ovarian germ cell tumor treatment for which both frozen sections and imprint cytology were available. Final histopathologic diagnoses were compared with those based on intraoperative examinations. Results: Underlying pathologies included dysgerminoma (n = 6), yolk sac tumor (n = 1), non-gestational choriocarcinoma (n = 1), mature cystic teratoma with malignant transformation (n = 1), immature teratoma (n = 11), and mixed germ cell tumor (n = 3). Discrepancies between intraoperative imprint cytology and definitive histologic diagnosis were seen in 6 of the 23 cases. Accuracy was 54.5% (6/11) for immature teratoma and 91.7% (11/12) for other tumors. Cytologic examination facilitated accurate diagnosis in both of our cases, and intraoperative diagnosis by frozen section proved inaccurate. Conclusion: These results demonstrate that intraoperative assessment based on imprint cytology for immature teratoma has a relatively lower sensitivity, but an acceptable sensitivity for other germ cell tumors. Diagnostic approaches combining frozen sections and imprint cytology are advisable to improve the yield for intraoperative diagnosis.