Background: Surgical resection with adjuvant chemotherapy is the standard of care for patients with pancreatic cancer, but to the authors' knowledge, little is known regarding the temporal relationship between chemotherapy initiation and survival. The current study analyzed the impact of time to the initiation of adjuvant chemotherapy.
Methods: The National Cancer Data Base (2003-2011) was retrospectively reviewed for patients with clinical American Joint Committee on Cancer stages I to III resected pancreatic carcinoma. Time to chemotherapy was stratified at the 12-week postoperative time point. Univariate and multivariate analyses were performed.
Results: The current study included 6706 patients who underwent surgical resection alone, 3723 patients who initiated adjuvant chemotherapy at ≤12 weeks, and 669 patients who initiated adjuvant chemotherapy at >12 weeks. Patients who received chemotherapy at >12 weeks were older and had greater comorbidities. Those undergoing a Whipple resection or total pancreatectomy were more likely to initiate chemotherapy later compared with those patients undergoing a distal surgical resection. Adjuvant chemotherapy conferred a survival benefit over surgical resection alone (P<.0001). There was no overall survival benefit observed for patients receiving adjuvant chemotherapy at ≤12 weeks compared with at >12 weeks (P =.5301). When stratified by pathological stage of disease, there was no survival benefit noted for the earlier initiation of chemotherapy: stage I: P =.2783; stage II: P =.0708; and stage III: P =.0778. After controlling for patient, disease, and surgery characteristics, both patients who initiated adjuvant chemotherapy at ≤12 weeks and at >12 weeks were found to have a 35% lower odds of mortality versus those who underwent surgical resection alone (P<.0001 for both).
Conclusions: The earlier initiation of adjuvant chemotherapy does not appear to significantly impact long-term survival in patients with resected pancreatic cancer. Because adjuvant chemotherapy confers a survival benefit, delayed chemotherapy should be offered when appropriate. Cancer 2016;122:2979-2987. © 2016 American Cancer Society.
Keywords: adjuvant chemotherapy; delayed chemotherapy; pancreatic adenocarcinoma; pancreatic cancer; timing; treatment.
© 2016 American Cancer Society.