Of the manuscripts reviewed, there was an overwhelming survival benefi t with radi­cal re- resection for incidentally discovered T1b tumors when compared to observa­tion alone. Abramson et al. evaluated this benefi t in a decision analysis study [ 8 ]. Twenty six studies with a combined total of 199 patients who underwent laparo­scopic cholecystectomy with a fi nal pathologic diagnosis of T1b gallbladder adeno­carcinoma were identifi ed. Of those, 158 patients underwent observation alone while 41 patients were offered a radical re-resection. The two groups were com­pared regarding 5-year survival and peri-operative mortality . Simple cholecystec­tomy alone resulted in a 61.3 % 5-year survival compared to 87.5 % for patients who underwent radical re-resection for T1b disease. The median survival following simple cholecystectomy was 6.42 years compared to 9.85 years in the group that underwent radical re-resection. Peri-operative mortality associated with radical re­resection was found to be 2 % (range: 0–6 %). Decision analysis was invoked to show that peri-operative mortality greater or equal to 36 % for radical re-resection would favor observation alone. Thus, the results demonstrate improved survival fol­lowing radical re-resection for T1b gallbladder cancer s, without unreasonably increased peri-operative risks [ 8 ]. In contrast, a smaller, retrospective case series evaluating T1b gallbladder cancers suggested no survival benefi t to radical re­resection over observation following simple cholecystectomy; however, the study may not have been suffi ciently powered to detect such a difference [ 9 ].

A larger epidemiologic study using the Surveillance, Epidemiology, and End Results (SEER) database analyzed whether Tis/T1/T2 incidentally found gallblad­der cancer s reported similar survival in patients who underwent extended surgical resection and lymphadenectomy versus simple cholecystectomy at the time of diag­nosis [ 18 ]. Increased survival was demonstrated in patients who underwent extended surgical resection compared with simple cholecystectomy alone, especially for patients with T2 tumors (p = 0.01) [ 18 ]. Poor prognostic survival factors included older patient age, increased T stage, and positive lymph nodes [ 18 ]. Moreover, patients who underwent resection of fi ve or more lymph nodes, especially for T2 tumors, demonstrated improved survival over no lymph nodes or only 1–4 lymph nodes excised (p < 0.001) [ 18 ].

In contrast to this, another SEER database study showed improved survival of radical resection for T2 tumors (p = 0.03) and T1 tumors (p = 0.02) [ 19 ]. The hazard ratio for death in a Cox multi-variable model for T1 tumors undergoing radical re­resection was 0.54 (95 % CI: 0.31–0.97, p = 0.04) [ 19 ]. Lymphadenectomy was also associated with improved survival for T2 (p < 0.001) and T3 (p < 0.001) tumors but not T1 tumors (p = 0.55) [ 19 ]. The hazard ratio for death in a Cox multi-variable model for T3 tumors undergoing lymphadenectomy was 0.70 (95 % CI: 0.48–1.00, p = 0.05) [ 19 ]. This data is supported by a large review from the Memorial Sloan- Kettering Cancer Center, that demonstrated residual disease risk of 50 % for T1 tumors, 61 % for T2 tumors, 85 % for T3 tumors, and 100 % for T4 tumors [ 20 ].