Hypothesis: Extended surgical resection (ESR) may improve survival in patients with early-stage primary gallbladder cancer.
Design: Retrospective analysis of findings in the Surveillance, Epidemiology, and End Results (SEER) database.
Setting: Academic research.
Patients: Individuals with potentially surgically curable gallbladder cancer (Tis, T1, or T2) who underwent a surgical procedure.
Main outcome measures: Overall survival, number of lymph nodes (LNs) excised, and results of simple cholecystectomy vs ESR.
Results: We identified 3209 patients with early-stage gallbladder cancer (11.7% Tis, 30.1% T1, and 58.2% T2). On multivariate analysis, decreased survival was noted among patients older than 60 years (hazard ratio, 1.57; 95% confidence interval, 1.30-1.90), among patients with more advanced cancer (1.99; 1.46-2.70 for T1; 3.29; 2.45-4.43 for T2), and among patients with disease-positive LNs (1.65; 1.39-1.95 for regional; 2.58; 1.54-4.34 for distant) (P < .001 for all), while increased survival was observed among female patients (0.82; 0.70-0.96; P = .02) and among patients undergoing ESR (0.59; 0.45-0.78; P < .001). The survival advantage of ESR was seen only in patients with T2 lesions (0.49; 0.35-0.68; P < .001). Lymph node excision data were available for a subset of 2507 patients, of whom 68.2% had no LN excised, 28.2% had 1 to 4 LNs excised, and 3.6% had 5 or more LNs excised. On multivariate analysis, patients with 1 to 4 LNs excised had a survival benefit over those with no LN excised (HR, 0.55; 95% CI, 0.46-0.66; P < .001), and patients with 5 or more LNs excised had a survival benefit over patients with 1 to 4 LNs removed (0.63; 0.40-0.96; P = .03). Lymph node excision improved survival in patients with T2 lesions (0.42; 0.33-0.53; P < .001 for patients with 1-4 LNs excised).
Conclusion: Extended surgical resection, LN excision, or both may improve survival in certain patients with incidentally discovered gallbladder cancer.