Delayed Initiation of S-1 Adjuvant Chemotherapy Impairs Survival in Patients With Curatively Resected Pancreatic...

The prognostic impact of the timing of adjuvant chemotherapy initiation in patients with resected pancreatic cancer is unclear. Therefore, this study aimed to investigate whether delayed initiation of S-1 adjuvant chemotherapy affects the survival of patients with resectable pancreatic cancer.

Patients who received S-1 adjuvant chemotherapy after undergoing R0/R1 resection were grouped according to whether adjuvant chemotherapy was initiated <60 (n=36) or ≥60 days (n=27) after surgery. Correlations between the time to chemotherapy initiation, clinicopathological factors, and survival were analyzed.

The median and mean times to chemotherapy initiation were 58 and 61 days, respectively. The delayed group had worse 2-year overall (57% vs. 80%, p=0.032) and recurrence-free survival (35% vs. 54%, p=0.044) rates than the early group. These results were similar in patients who completed S-1 adjuvant chemotherapy. In multivariate analysis, delayed initiation of chemotherapy, R1 resection, and tumor size (≥40 mm) were independent prognostic factors for poor overall survival. The delayed group had more patients with severe postoperative complications (Clavien-Dindo grade ≥III) (30% vs. 8%, p=0.028) and delayed recovery of serum albumin levels (postoperative days 7, 14, and 30: p=0.040, 0.004, and 0.003, respectively) than the early group.

Delayed initiation of S-1 adjuvant chemotherapy had an adverse impact on survival and was correlated with severe postoperative complications and delayed recovery of postoperative nutritional status.