Kate Mlouk, Camila Hidalgo Salinas, Jonah Levine, Joseph R Habib, Madeleine Hunter, Rami Imam, D Brock Hewitt, Michael D Kluger, Katherine Morgan, Lois A Daamen, Christopher L Wolfgang, I Quintus Molenaar, Marc G Besselink, Ammar A Javed, Greg D Sacks
In patients with resected IPMN-derived PDAC, ductal subtype was not significantly associated with OS. While clinically meaningful differences in RFS cannot be excluded, these findings suggest that once invasive cancer arises and is resected, ductal subtype alone may not provide additional prognostic information.
BACKGROUND: Although main duct (MD) and branch duct (BD) IPMNs differ in preoperative risk of malignant transformation, it remains unclear whether ductal subtype influences outcomes once invasive carcinoma develops and is resected. We compared recurrence and survival outcomes between these subtypes.
METHODS: We identified patients with resected IPMN-derived pancreatic ductal adenocarcinoma (PDAC) from three institutions. Overall survival (OS) and recurrence-free survival (RFS) were estimated using Kaplan-Meier methods and compared with log-rank tests. Multivariable Cox regression models adjusted for age, T-stage, N-stage, histologic subtype, and adjuvant chemotherapy.
RESULTS: Among 136 patients, 106 (78%) had MD-derived and 30 (22%) had BD-derived IPMN-associated PDAC. Median OS was 36.6 months and did not differ by subtype on log-rank (p = 0.472) or multivariable analysis (HR 0.45, 95% CI 0.15-1.31; p = 0.143). Median RFS was 41.8 months without significant difference by subtype on log-rank (p = 0.362) or adjusted analysis (HR 0.56, 95% CI 0.21-1.46; p = 0.234).
CONCLUSIONS: In patients with resected IPMN-derived PDAC, ductal subtype was not significantly associated with OS. While clinically meaningful differences in RFS cannot be excluded, these findings suggest that once invasive cancer arises and is resected, ductal subtype alone may not provide additional prognostic information.