Multi-Institutional Analysis of Pancreaticoduodenectomy for Nonfamilial Periampullary Adenoma: A Novel Risk Score to Guide Shared Decision-Making

BACKGROUND: Pancreaticoduodenectomy (PD) may occasionally be indicated for complete removal of periampullary (duodenal and ampullary) adenomas (PAs). As compared with malignant indications, PD for benign or premalignant disease is often associated with increased morbidity. Although the Spigelman classification assesses malignancy risk for familial adenomatous polyposis (FAP)-related duodenal adenomas, no malignancy risk score (MRS) exists for non-FAP-related PAs. We developed an MRS for non-FAP-related PAs undergoing PD to weigh the risk of malignancy and postoperative morbidity. STUDY DESIGN: We retrospectively analyzed patients with non-FAP-related PA who underwent PD at 8 institutions (2010 to 2022). Patient and lesion factors associated with final malignant pathology were identified using multivariable logistic regression to create MRS. Postoperative complications were assessed according to MRS. RESULTS: Of 127 patients, 59 (46.5%) had evidence of malignancy on final pathology. The odds of malignancy were higher in patients aged 65 years or older (odds ratio [OR] 3.2, p = 0.01), having bile duct 9 mm or more (OR 3.3, p = 0.009), having preoperative symptoms (OR 7.7, p = 0.002), and having high-grade dysplasia (OR 7.5, p < 0.001). A MRS was derived ranging from 0 to 6: age 65 years or older = 1, bile duct 9 mm or more = 1, symptomatic = 2, and high-grade dysplasia = 2. Patients were stratified into low-risk (MRS 1 to 2, n = 26), intermediate-risk (MRS 3 to 4, n = 59), and high-risk groups (MRS 5 to 6, n = 26), with malignancy rates increasing with MRS (10.3%, 44.1%, and 88.2%, p < 0.001). Patients in the no- or low-risk group (MRS 0 to 2) had higher odds of major postoperative complications compared with patients in the intermediate- or high-risk group (MRS 3 or higher, OR 2.9, p = 0.047). CONCLUSIONS: This novel MRS stratifies the risk of malignancy in non-FAP-related PAs managed with PD. This score can be used to counsel patients who may require PD for complete tumor removal about their risk of harboring malignancy and their risk of major postoperative complications.