Timing of TS1 adjuvant chemotherapy as a prognostic factor in recurrent pancreatic cancer after surgery

Aim: Prognosis of pancreatic cancer is improved by combining postoperative adjuvant chemotherapy and preoperative adjuvant chemotherapy with surgery, while the importance of extended dissection surgery has decreased. To better understand prognostic factors of recurrence, we focused on the timing of postoperative adjuvant chemotherapy in patients with pancreatic cancer. Methods: One hundred patients who underwent pancreatectomy or pancreaticoduodenectomy and chemotherapy for pancreatic cancer were classified into early and late postoperative adjuvant therapy initiation groups. Prognosis was evaluated retrospectively using known prognostic factors. Results: On receiver operating characteristic analysis, optimum cut-off between the early (<52 days; n = 60) and late adjuvant initiation groups (>= 52 days; n = 40) was 52 days. The two groups were well-matched, except the early initiation group had more surgeries with D2 lymph node dissection (75 % vs 48 %; p = 0.01); fewer postoperative complications (17 % vs 59 %; p = 0.04), including less postoperative pancreatic fistula (13 % vs 35 %; p = 0.03); and longer disease-free survival (0.7 years v 0.5 years; p = 0.02). On multivariate evaluation, early initiation and completion of adjuvant therapy were associated with increased overall survival, while early initiation was associated with prolonged disease-free survival. Conclusions: Prognosis of patients with pancreatic cancer is improved by earlier rather than later initiation of postoperative adjuvant therapy.