Comparative Study of Pancreatic Acinar Cell Carcinoma and Pancreatoblastoma: Insights From the National Cancer Database.

[INTRODUCTION] Pancreatic acinar cell carcinoma (pACC) and pancreatoblastoma (PBL) are rare pancreatic neoplasms with overlapping clinical and histological features. This study aims to compare the clinical presentation, treatment strategies, and survival outcomes of pACC and PBL using data from the National Cancer Database.

[METHODS] Data from the National Cancer Database (2004-2019) were analyzed for adult patients with pACC (n = 1416) and PBL (n = 32). Overall survival (OS) was assessed using Kaplan-Meier curves and log-rank tests. Multivariate Cox proportional hazards models evaluated factors impacting survival.

[RESULTS] Both tumors commonly presented in the pancreatic head (40.6% PBL, 41.2% pACC, P = 0.99) with high rates of stage four disease (53.1% PBL, 46.5% pACC, P = 0.25). PBL exhibited higher neoadjuvant chemotherapy use (30.0% versus 13.6%, P = 0.038) and surgical resection rates (68.8% versus 41.0%, P = 0.002). The median OS was 59.8 months for PBL and 22.8 months for pACC (P = 0.070). Among stage four patients, PBL had significantly longer median OS (24.1 versus 11.2 months, P = 0.015). Multivariable analysis among resected patients identified age >65 y (hazard ratio [HR] = 1.59; 95% confidence interval [CI]: 1.24-2.05), stage four disease (HR = 1.88; 95% CI: 1.18-2.99), positive lymph node ratio (1%-20%: HR = 2.38; 95% CI: 1.65-3.42; >20%: HR = 1.84; 95% CI: 1.31-2.58), and R1 margins (HR = 1.79; 95% CI: 1.24-2.59) as predictors of higher mortality. Adjuvant chemotherapy was associated with improved survival (HR = 0.68; 95% CI: 0.52-0.88).

[CONCLUSIONS] pACC and PBL share similar presentations, but PBL patients exhibit higher resection rates and better stage four survival. Complete resection and adjuvant chemotherapy independently predict improved survival in both groups.