Background: Pancreatic ductal adenocarcinoma (PDAC) arising in intraductal papillary mucinous neoplasms (IPMN) may represent a different biologic entity than classic PDAC, and there is little evidence to inform adjuvant treatment decisions. The purpose of this study was to identify prognostic factors for PDAC arising in IPMN and determine the benefit of postoperative adjuvant therapy.
Methods: Forty-four patients without previous therapy who underwent surgery for invasive PDAC arising in association with IPMN at our institution were identified. Medical records were reviewed for clinical and pathologic features, adjuvant therapy, and outcomes.
Results: On univariate analysis, positive nodes (hazard rate [HR] 14, 95% confidence interval [CI] 4.2-44), CA 19-9 > 80 (HR 6.2, 95% CI 2.2-17), lymphovascular invasion (HR 4.7, 95% CI 1.5-15), perineural invasion (HR 3.9, 95% CI 1.5-10), and positive margins (HR 3.1, 95% CI 1.2-8.0) were associated with inferior cancer-specific survival. Patients with positive nodes who received adjuvant therapy had higher median cancer-specific survival (20 months) than those who received no adjuvant therapy (3.3 months).
Conclusions: Patients with PDAC arising in IPMN presented at an earlier stage than is reported for classical PDAC. Adjuvant chemoradiotherapy was associated with improved overall and cancer-specific survival for patients with advanced disease. These hypothesis-generating results require validation in a larger prospective trial.