Abstract
BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a rare and aggressive disease with an increasing incidence in the United States, and there is no level 1 evidence to help guide treatment decisions. We sought to determine national trends in surgical and medical management of patients with resected ICC, and more specifically, the role of lymphadenectomy (LAD) and utilization of chemotherapy. METHODS: An augmented version of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) cancer database registry was used to identify all surgically resected ICC patients from 2000 to 2014. We evaluated the incidence and adequacy of LAD, and receipt of chemotherapy over time. Next, multivariable logistic regressions were performed to determine the predictors of LAD and receipt of chemotherapy. Overall survival (OS) was evaluated using Kaplan-Meier and Cox proportional hazard models. RESULTS: We identified 1,263 patients who underwent resection for ICC. Lymph nodes (LNs) were removed in 49% of patients, however, only 10% of patients received adequate LAD by the American Joint Committee on Cancer (AJCC) criteria (≥6 nodes). LN metastases were found in 29% of patients who underwent nodal evaluation. Chemotherapy was administered to 40% of patients, was utilized more frequently over time (P<0.05), and was associated with improved survival in node positive patients (P<0.05). Patients who did not have LNs evaluated were significantly less likely to receive chemotherapy than those who did. Lastly, OS for the entire cohort improved over time (P<0.05). CONCLUSIONS: After analyzing the treatment and outcomes of resectable ICC, we concluded: (I) LN evaluation at the time of surgical resection remains inadequate; (II) utilization of chemotherapy has increased over time; (III) the lack of LAD likely results in under-staging and underutilization of chemotherapy; and (IV) despite less than ideal surgical and medical therapy median OS continues to improve.