Does Adjuvant Therapy Benefit Low-Risk Resectable Cholangiocarcinoma? An Evaluation of the NCCN Guidelines

Background The National Comprehensive Cancer Network (NCCN) guidelines recommend adjuvant therapy for patients with resectable cholangiocarcinoma (CCA). The trends in utilization and receipt of adjuvant therapy and its association with overall survival have not been well studied among patients with low-risk CCA. Methods Patients who received systemic chemotherapy for low-risk CCA after surgical resection (2010-2017) were identified in the National Cancer Database. Low-risk CCA was defined according to NCCN guidelines as patients with R0 margins and negative regional lymph nodes. Multivariable analysis was performed to assess predictors of NCCN guideline concordance and its association with overall survival. Results Among 4519 patients who underwent resection for low-risk CCA, 55.5% (n = 2510) had intrahepatic, 15.0% (n = 680) had perihilar, and 29.4% (n = 1329) had distal cholangiocarcinoma. Adherence to NCCN guidelines increased from 27.7% in 2010 to 41.6% in 2017 (ptrend < 0.001) for low-risk CCA. On multivariable analysis, receipt of NCCN guideline-concordant care was associated with a nearly 15% decrease in mortality hazards (HR 0.86, 95%CI 0.78-0.95, p < 0.05). Increased distance travelled (Ref < 12.5 miles, 50-249 miles: OR 0.55, 95%CI 0.49-0.69; >= 250 miles: OR 0.41, 95%CI 0.25-0.6), and care in the South (OR 0.78, 95%CI 0.64-0.95) or Midwest (OR 0.66, 95%CI 0.53-0.81) of the United States versus the Northeast was associated with not receiving guideline-concordant care. Conclusion Adherence to evidence-based NCCN guidelines was associated with improved survival among low-risk CCA patients. Geographical disparities in the receipt of NCCN guideline-concordant care exist and may influence long-term outcomes among CCA patients.