Branch-duct intraductal papillary mucinous neoplasms: observations in 145 patients who underwent resection

Abstract

Background & aims: Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas arising in branch ducts are thought to be less aggressive than their main-duct counterparts, and guidelines for their conservative management were recently proposed. This study describes the combined experience of 2 tertiary centers with branch-duct IPMNs aiming to validate these recommendations.

Methods: A review of 145 patients with resected, pathologically confirmed, branch-duct IPMNs between 1990 and 2005 was conducted.

Results: Sixty-six patients (45.5%) had adenoma, 47 (32%) borderline tumors, 16 (11%) carcinoma in situ, and 16 (11%) invasive carcinoma. Median age was similar between benign and malignant subgroups (66 vs 67.5 years, respectively). Jaundice was more frequent in patients with cancer (12.5% vs 1.8%, respectively, P = .022) and abdominal pain in patients with benign tumors (45% vs 25%, respectively, P = .025). Forty percent of tumors were discovered incidentally. Findings associated with malignancy were the presence of a thick wall (P < .001), nodules (P < .001), and tumor diameter >or=30 mm (P < .001). All neoplasms with cancer were larger than 30 mm in size or had nodules or caused symptoms. After a mean follow-up of 45 months, the 5-year disease-specific survival for branch-duct IPMNs with noninvasive neoplasms was 100% and, for invasive cancer, was 63%.

Conclusions: This large cohort of resected branch-duct IPMNs shows that cancer is present in 22% of cases and validates the recent guidelines that indicate absence of malignancy in tumors <30 mm, without symptoms or mural nodules.

Figure 1

(A) Distribution of overall number of pancreatic resections by year for branch-duct IPMNs (n =145). (B) Symptomatic vs incidentally discovered pancreatic resections for branch-duct IPMNs (2002–2005).

Figure 2

Scatter plot of radiologic tumor size as a function of histologic subtype and presence or absence of symptoms and nodules.

Figure 3

(A) Overall 5- and 10-year survival for the entire series were 95% and 70%, respectively. (B) The 5-year disease-specific survival was 100% for patients affected by adenoma, borderline, or carcinoma in situ and 63% for the 16 patients with invasive carcinoma.