The impact of adjuvant therapy on outcome in UICC stage I pancreatic cancer

Adjuvant chemotherapy has become standard of care for pancreatic ductal adenocarcinoma (PDAC) as it improves patient outcome. However, its clinical meaning in early‐stage, UICC I tumors remains uncertain. We examined the effect of adjuvant therapy on disease‐free survival (DFS) and overall survival (OS) of UICC stage I PDAC patients treated at an academic tertiary care center between 2000 and 2016. Among 124 patients (69 male, 55 female; median age 68 years, range 41‐84 years) with UICC stage I disease, adjuvant therapy improved both DFS (19.8 vs 12.8 months, HR 0.59, 95% CI: 0.37‐0.94, P = .03) and OS (40.9 vs 20.3 months, HR 0.54, 95% CI: 0.35‐0.84, P = .005). Multivariate analyses and propensity score matching confirmed the prognostic impact of adjuvant therapy independent of localization, differentiation and R‐status. Thus, every patient with UICC I PDAC should receive adjuvant chemotherapy as it may improve outcome significantly. Our findings support the concept of PDAC as systemic disease from early stages on. What's new? The incidence of early‐stage pancreatic ductal adenocarcinoma (PDAC) is on the rise, casting new light on pre‐existing therapeutic challenges. Overcoming these challenges may be possible with adjuvant chemotherapy, though little is known about its clinical relevance for early‐stage disease. The present study examined the impact of adjuvant chemotherapy on survival specifically among stage I PDAC patients. Analyses show that the approach significantly improves disease‐free and overall survival, with 5‐year survival rate about 26.6% among adjuvant therapy‐treated patients and 10.5% for nonadjuvant patients. The findings suggest that adjuvant chemotherapy should be offered to all PDAC patients after resection.