OBJECTIVE This study was performed to evaluate the outcome of patients with gallbladder cancer who received postoperative concurrent chemotherapy and radiation therapy. METHODS Curative resection followed by adjuvant combined modality therapy with external beam radiation therapy (EBRT) and chemotherapy was attempted in 21 consecutive gallbladder carcinoma (GBC) patients at the Mayo Clinic from 1985 through 1997. All patients received concurrent 5-fluorouracil during EBRT. EBRT fields encompassed the tumor bed and regional lymph nodes (median dose of 54 Gy in 1.8-2.0-Gy fractions). One patient received 15 Gy intraoperatively after EBRT. A retrospective analysis was performed for the end points of local control, distant failure, and overall survival. RESULTS After maximal resection, 12 patients had no residual disease on pathologic evaluation, 5 had microscopic residual disease, and 4 had gross residual disease. One patient had Stage I disease, and 20 had Stage III-IV disease. With median follow-up of 5 years (range: 2.6-11.5 years), 5-year survival for the entire cohort was 33%. The 5-year survival rate of patients with Stage I-III disease was 65% vs. 0% for those with Stage IV disease (p < 0.02). For patients with no residual disease, 5-year survival was 64% vs. 0% for those with residual disease (p = 0.002). The median survival was 0.6, 1.4, and 5.1 years for patients with gross residual, microscopic residual, and no residual disease, respectively (p = 0.02). The 5-year local control rate for the entire cohort was 73%. Two-year local control rates were 0%, 80%, and 88% for patients with gross residual, microscopic residual, or no residual disease, respectively (p < 0.01). Five-year local control rates were 100% for the 6 patients who received total EBRT doses >54 Gy (microscopic residual, 3 patients; gross residual, 1 patient; negative but narrow margins, 2 patients) vs. 65% for the 15 who received a lower dose (3, gross residual; 2, microresidual; 10, negative margins). CONCLUSIONS Patients with completely resected (negative margins) GBC followed by adjuvant EBRT plus 5-fluorouracil chemotherapy had a relatively favorable prognosis, with a 5-year survival rate of 64%. These results seem to be superior to historical surgical controls from the Mayo Clinic and other institutions, which report 5-year survival rates of approximately 33% with complete resection alone. Both tumor stage and extent of resection seemed to influence survival and local control. More aggressive measures using current cancer therapies and integration of new cancer treatment modalities will be required to favorably impact on the poor prognosis of patients with Stage IV or subtotally resected GBC. Additional investigation leading to earlier diagnosis is warranted, because most patients with GBC present with advanced disease.