Despite recent completion of several trials of adjuvant therapy after resection for pancreatic adenocarcinoma, the absolute impact on survival and the identification of appropriate patients for treatment remains controversial.
We sought to identify the impact of adjuvant therapy and factors associated with any improvement in survival after resection of pancreatic cancer.
Through the California Cancer Registry, we identified all California residents diagnosed with pancreatic cancer between 1994 and 2002. Factors potentially impacting survival were analyzed, including: patient demographics, tumor characteristics, and treatment provided. Univariate and multivariate survival analyses were performed by Kaplan-Meier and Cox regression methods.
26,518 patients were identified; 3,196 (12.1%) underwent resection as their primary treatment. The median overall survival was 16 months for resected patients. Prognostic factors associated with better survival included: negative lymph node status, well differentiated tumors, younger age, female gender, and receipt of any adjuvant therapy. On multivariate analysis, adjuvant therapy demonstrated a statistically significant, though modest, impact on survival with a hazard ratio of 0.79 (95% CI 0.72 – 0.87, p<0.001). The benefit of adjuvant therapy was only apparent in those patients with lymph node positive or poorly differentiated tumors.
Adjuvant therapy provides for a modest improvement in overall survival following surgical resection of pancreatic cancer. The absolute effect is most pronounced in those with poor prognostic indicators. In order to identify effective systemic therapy for this deadly cancer, future clinical trials of adjuvant therapy should focus on these groups of patients.