Role of intraoperative frozen section in detection and surgical decision-making of suspected gallbladder cancer during laparoscopic cholecystectomy.

Abstract

e16026 Background: Gallbladder cancer (GBC) is an aggressive malignancy with a high incidence in India and is frequently diagnosed at an advanced stage due to nonspecific clinical and radiologic findings. Incidental or intraoperatively suspected GBC during laparoscopic cholecystectomy (LC) represents a critical window for early diagnosis. Intraoperative frozen section (FS) examination may facilitate real-time diagnosis, staging, and appropriate surgical escalation, potentially avoiding re-operations. We evaluated the diagnostic accuracy and clinical utility of FS in suspected GBC during LC. Methods: This retrospective observational study included patients undergoing LC at a tertiary care center between January 2020 and December 2021. Among 1,835 LCs performed, 94 cases with intraoperative suspicion of malignancy underwent FS evaluation. FS samples were obtained from the cystic duct margin, neck, body, and fundus. FS diagnoses were correlated with final paraffin-embedded histopathology, which served as the reference standard. Tumors were staged according to the AJCC TNM system. Diagnostic performance parameters including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. The impact of FS findings on intraoperative surgical decision-making was analyzed. Results: Of the 94 FS-evaluated cases, 26 (27.7%) were confirmed as carcinoma on final histopathology. Xanthogranulomatous cholecystitis was the most common benign mimic. FS correctly identified malignancy in 23 of 26 cases, yielding a sensitivity of 88.5% and specificity of 100%. PPV and NPV were 100% and 95.8%, respectively. Three false-negative cases were attributed to sampling limitations in dysplastic or inflammatory lesions. Pathologic staging revealed pT1b disease in 19.2%, pT2 in 61.5%, and pT3 in 19.2% of patients, with no distant metastases detected. FS findings enabled appropriate intraoperative conversion to radical surgery, including hepatic resection and lymphadenectomy, in eligible patients, thereby reducing the need for second surgeries. Conclusions: Intraoperative frozen section analysis during LC demonstrates high specificity and clinically meaningful sensitivity for detecting unsuspected GBC. FS plays a pivotal role in real-time diagnosis, staging, and surgical decision-making, optimizing oncologic management and minimizing re-interventions. Adequate sampling and experienced pathological interpretation are essential to maximize diagnostic accuracy.