Single stage management of suspected gallbladder cancer guided by intraoperative frozen section analysis: a retrospective cohort study.

Background: The management of radiologically suspected gallbladder cancers (GBC) that lack definitive radiological features usually involves performing a first-stage routine laparoscopic cholecystectomy, followed by an open second-stage liver resection (segments IVB and V) and hilar lymphadenectomy (extended cholecystectomy) if subsequent formal histology confirms a malignancy. Performing a cholecystectomy with an intraoperative frozen section to guide the need for conversion to an extended cholecystectomy as a single-stage procedure has multiple benefits compared to a two-stage approach. However, the safety and efficacy of this approach have not yet been evaluated in a tertiary setting.

Methods: A retrospective cohort study was performed using a database of all consecutive patients with suspected GBC who had been referred to our tertiary unit. Following routine cholecystectomy, depending on the operative findings, the gallbladder specimen was removed and sent for frozen-section analysis. If malignancy was confirmed, the depth of tumour invasion was evaluated, followed by simultaneous extended cholecystectomy, when appropriate. The sensitivity and specificity of frozen section analysis for the diagnosis of GBC were measured using formal histopathology as a reference standard.

Results: A total of 37 consecutive cholecystectomies were performed. In nine cases, GBC was confirmed by intraoperative frozen section analysis, three of which had standard cholecystectomy only as their frozen section showed adenocarcinoma to be T1a or below ( n =2) or were undetermined ( n =1). In the remaining six cases, malignant invasion beyond the muscularis propria (T1b or above) was confirmed; thus, a synchronous extended cholecystectomy was performed. The sensitivity (95% CI: 66.4-100%) and specificity (95% CI: 87.7-100%) for identifying GBC using frozen section analysis were both 100%. The net cost of the single-stage pathway in comparison to the two-stage pathway resulted in overall savings of £3894.

Conclusion: Intraoperative frozen section analysis is a reliable tool for guiding the use of a safe, single-stage approach for the management of GBC in radiologically equivocal cases. In addition to its lower costs compared to a conventional two-stage procedure, intraoperative analysis also affords the benefit of a single hospital admission and single administration of general anaesthesia, thus greatly enhancing the patient's experience and relieving the burden on waiting lists.