Real-world patterns of adjuvant chemotherapy treatment for patients with resected pancreatic adenocarcinoma.

The aim of the study was to analyze the real-world treatment patterns of adjuvant chemotherapy administration among patients with resected pancreatic adenocarcinoma. Cases with non-metastatic pancreatic adenocarcinoma, diagnosed 2007-2018, treated with upfront surgical resection, and recorded within Alberta Cancer registry were accessed. Multivariable logistic regression analysis was conducted to evaluate factors predicting use of adjuvant chemotherapy. Kaplan-Meier survival estimates and multivariable Cox regression analysis were used to compare overall survival among patients treated with adjuvant gemcitabine versus those treated with adjuvant gemcitabine + capecitabine. A total of 695 patients who have undergone upfront surgical treatment of pancreatic adenocarcinoma, including 445 patients (64%) who received adjuvant chemotherapy and 250 patients (36%) who did not receive adjuvant chemotherapy. The following factors were associated with lower probability to receive adjuvant chemotherapy: older age (OR 0.94; 95% CI 0.93-0.96), node negativity (OR 0.47; 95% CI 0.33-0.67), higher Charlson comorbidity index (OR 0.86; 95% CI 0.74-0.99), and living within the Northern zone of the province (OR for Calgary zone versus North zone: 2.24; 95% CI 1.29-3.90). Within patients who received adjuvant gemcitabine ± capecitabine, factors associated with worse overall survival included higher Charlson comorbidity index (HR 1.18; 95% CI 1.00-1.40), and node-positive disease (HR for node-negative versus node-positive disease: 0.51; 95% CI 0.33-0.78). Type of chemotherapy was not predictive of overall survival (HR for gemcitabine versus gemcitabine plus capecitabine: 1.40; 95% CI 0.98-2.00). P value for interaction between type of chemotherapy and nodal status was 0.038. In this real-world study, the added benefit of adjuvant gemcitabine + capecitabine (compared to adjuvant gemcitabine) seems to be limited to patients with node-positive disease.