Important radiological and clinicopathological risk factors for the recurrence of intraductal papillary mucinous neoplasms after surgical resection.

Abstract

To assess significant radiological and clinicopathological risk factors for post-surgery recurrence in patients with intraductal papillary mucinous neoplasm (IPMN). Patients with IPMNs who underwent surgery from 2011 to 2021 at a single center were retrospectively included. Two reviewers evaluated CT findings according to international guidelines. Clinicopathological data were collected from medical records and surgical pathology reports. Patients were monitored for recurrence with contrast-enhanced CT or MRI up to 2023. Univariable Cox regression analysis included potential risk factors: all high-risk stigmata and worrisome features in the international guidelines, age, sex, tumor location, type, carcinoembryonic antigen, surgery type, postsurgical residual cyst, adjuvant treatment, pathologic grade, type, size, margin status, lymph node metastasis, gland type, and pancreatic intraepithelial neoplasia. Variables with p < 0.2 were included in multivariate analysis. Among 332 patients (mean age, 66.3 ± 9.0 years; 212 men), recurrence occurred in 39 (11.7%) over a median follow-up of 3.2 years (range: 0.1-12.3 years). Two- and five-year recurrence-free survival rates were 91.2% and 86.4%, respectively. Significant radiological risk factors included enhancing mural nodule (EMN) presence (hazard ratio [HR] 5.088, p = 0.007) and lymphadenopathy (HR 2.837, p = 0.01). Associated invasive carcinoma (HR 25.030), lymph node metastasis (HR 27.562), adjuvant treatment (HR 0.203), and history of pancreatitis (HR 2.608) were also significant. Most imaging features showed moderate to excellent interobserver agreement, except for thickened/enhancing cyst walls (κ, 0.25). The presence of EMNs and lymphadenopathy, along with several clinicopathologic factors, were significantly associated with IPMN recurrence. Question Understanding postoperative recurrence risk in IPMN patients is crucial for determining surveillance strategies; however, research on radiologic risk factors remains limited. Findings The presence of EMNs and lymphadenopathy were identified as significant radiologic risk factors for the postoperative recurrence of IPMN, along with clinicopathologic factors. Clinical relevance IPMN recurrence is significantly associated with imaging findings like EMNs and lymphadenopathy, as well as clinical and pathologic factors. It can guide the development of tailored postoperative surveillance strategies for IPMN patients in further studies.