Prognostic factors of recurrence in patients with recurrent postoperative pancreatic cancer treated with adjuvant TS-1 as the main outcome

Purpose 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. Here, to better understand prognostic factors of recurrence, we focused on the timing of postoperative adjuvant chemotherapy in patients with pancreatic cancer. Materials and 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 of adjuvant therapy and completion of adjuvant therapy were associated with increased overall survival, while early initiation was associated with prolonged disease-free survival. Conclusion Prognosis of patients with pancreatic cancer is improved by earlier rather than later initiation of postoperative adjuvant therapy. While surgery remains a key treatment approach, its main contribution to prognosis may derive from minimization of dissection and complications.