High quality surgery for gallbladder carcinoma is infrequently practiced and associated with predicable factors

Abstract

Presenter: Omid Salehi MD | Saint Elizabeth's Medical Center Background: Resectable T1b-T3 Gallbladder Carcinoma (GBC) is optimally treated with oncologic extended R0 resection that includes gallbladder fossa resection or bisegmentectomy IVb/V, portal- and retroperitoneal lymphadenectomy. However, optimal oncologic surgery for GBC is infrequently practiced and this study aims at identifying factors associated with suboptimal surgery. Methods: The National Cancer Database was queried for patients diagnosed with Stage 1-3 (T1b-T3) GBC undergoing high quality surgery (HQS) between 2004-2016. HQS was defined as partial hepatectomy with cholecystectomy, lymph node harvest ≥6 and negative margins. Logistic regression was used to assess demographic, socioeconomic, tumor, and hospital level factors associated with HQS. Chi-squared tests, Kaplan-Meier survival analyses and log rank tests were performed. Results: 4731 patients met inclusion criteria; 393 (8.3%) met HQS and 4338 (91.7%) had inadequate surgery per above parameters. HQS was associated with improved median overall survival (55.1 vs 24.1 months, P < .001) even if inadequate surgery achieved R0 margins (55.1 vs 32.9 months, P < .001). HQS also had less 30-day and 90-day mortality (30d: 1.8% vs 4.5%, P = .020; 90d: 3.1% vs 10.7%, P < .001). Factors associated with receipt of HQS included: private insurance (vs government options, OR 1.874, P < .001), urban/rural residence (vs metropolitan, OR 1.729, P < .001), living in a Medicaid Expansion state (OR 1.366, P = .006), Stage 2 and 3 GBC (vs stage 1, OR 1.562, P = .034), neoadjuvant chemotherapy (OR 2.370, P = .037), increased distance from patient’s residence to reporting hospital (OR 1.001, P = .040), and longer time from diagnosis to definitive surgery (OR 1.005, P < .001). Factors associated with poorer HQS rate included: older age (OR 0.967, P < .001), Charleson-Deyo Comorbidity Score ≥1 (OR 0.732, P = .007), and laparoscopic approach (vs open, 0.536, P < .001). Facility type improved HQS rate incrementally by institution type; comprehensive community had better HQS than community (4.9% vs 2.4%, OR 2.105, P = .021), as did integrated cancer network vs comprehensive community (8.4% vs 4.9%, OR 1.789, P = .001), and academic/research center vs integrated cancer network (14% vs 8.4%, OR 1.782, P < .001). Conclusion: Nationally, HQS for T1b-T3 GBC is infrequently practiced and modifiable factors are predictive. Centralization of surgery to higher volume hospitals, open approach, and insurance status improves HQS rates and survival. Improved HQS rates for stage 2 and 3 GBC may suggest stage 1 GBC is particularly at risk for inadequate surgery. Further, while Medicaid expansion has improved patient’s ability to have HQS, disparity compared to private insurance carriers still exists. The impact of low-quality surgery for GBC on survival and the high frequency of which it is practiced, calls for intervening on modifiable factors to improve survival for GBC.