Association of Preoperative Risk Factors With Malignancy in Pancreatic Mucinous Cystic Neoplasms

Abstract

IMPORTANCE Pancreatic mucinous cystic neoplasms (MCNs) harbor malignant potential, and current guidelines recommend resection. However, data are limited on preoperative risk factors for malignancy (adenocarcinoma or high-grade dysplasia) occurring in the setting of an MCN. OBJECTIVES To examine the preoperative risk factors for malignancy in resected MCNs and to assess outcomes of MCN-associated adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS Patients who underwent pancreatic resection of MCNs at the 8 academic centers of the Central Pancreas Consortium from January 1, 2000, through December 31, 2014, were retrospectively identified. Preoperative factors of patients with and without malignant tumors were compared. Survival analyses were conducted for patients with adenocarcinoma. MAIN OUTCOMES AND MEASURES Binary logistic regression models were used to determine the association of preoperative factors with the presence of MCN-associated malignancy. RESULTS A total of 1667 patients underwent resection of pancreatic cystic lesions, and 349 (20.9%) had an MCN (310 women [88.8%]; mean (SD) age, 53.3 [14.7] years). Male sex (odds ratio [OR], 3.72; 95% CI, 1.21–11.44; P = .02), pancreatic head and neck location (OR, 3.93; 95% CI, 1.43–10.81; P = .01), increased radiographic size of the MCN (OR, 1.17; 95% CI, 1.08–1.27; P < .001), presence of a solid component or mural nodule (OR, 4.54; 95% CI, 1.95–10.57; P < .001), and duct dilation (OR, 4.17; 95% CI, 1.63–10.64; P = .003) were independently associated with malignancy. Malignancy was not associated with presence of radiographic septations or preoperative cyst fluid analysis (carcinoembryonic antigen, amylase, or mucin presence). The median serum CA19-9 level for patients with malignant neoplasms was 210 vs 15 U/mL for those without (P = .001). In the 44 patients with adenocarcinoma, 41 (93.2%) had lymph nodes harvested, with nodal metastases in only 14 (34.1%). Median follow-up for patients with adenocarcinoma was 27 months. Adenocarcinoma recurred in 11 patients (25%), with a 64% recurrence-free survival and 59% overall survival at 3 years. CONCLUSIONS AND RELEVANCE Adenocarcinoma or high-grade dysplasia is present in 14.9% of resected pancreatic MCNs for which risks include male sex, pancreatic head and neck location, larger MCN, solid component or mural nodule, and duct dilation. Mucinous cystic neoplasm-associated adenocarcinoma appears to have decreased nodal involvement at the time of resection and increased survival compared with typical pancreatic ductal adenocarcinoma. Indications for resection of MCNs should be revisited.

Pancreatic Cystic Neoplasms: Different Types, Different Management, New Guidelines

“…There is no connection between the cyst and the pancreatic duct. Several characteristics, such as cyst size and mural nodules, are associated with the grade of malignancy [17,22,23]. The recent European guideline is the first to highlight the low risk of malignancy when MCN are smaller than 40 mm [6].…”

“…In MCN, cyst size is associated with the risk of malignancy [22,23]. The European guideline is the first to advise a conservative approach when the cyst size is <40 mm.…”

The diagnosis of pancreatic mucinous cystic neoplasm and associated adenocarcinoma in males: An eight‐institution study of 349 patients over 15 years

“…Current guidelines recommend complete resection of all suspected MCNs due to the risk of associated high‐grade dysplasia and invasive adenocarcinoma, which ranges between 10% to as high as 46% in the literature . Thus, achieving an accurate diagnosis of MCN is paramount, yet can be difficult due to the often overlapping clinical, radiographic, cytologic, and histopathologic features with branch‐duct IPMNs.…”

“…One of the most striking clinical features unique to MCNs is that they occur almost exclusively in the pancreatic body and tail of premenopausal women . Still, based on the 2000 WHO criteria, MCNs do occur in males, and male gender has been associated with a higher malignant potential, yet these patients are a group that has largely been unstudied . The purpose of this study was utilize a large, multi‐institutional database to characterize MCNs and assess the incidence of associated adenocarcinoma/high‐grade dysplasia (AC/HGD) in males compared to females over time.…”

Benign Tumors of the Pancreas—Radical Surgery Versus Parenchyma-Sparing Local Resection—the Challenge Facing Surgeons

“…Mucinous cystic neoplasms (MCNs) are located in 80% of cases in the body and tail and in 15% in the pancreatic head, 85% found in middleaged female patients. 26,27 Serous pseudo-papillary neoplasms (SPNs) develop more frequently in female patients aged 40 to 50 years and are equally distributed throughout the pancreas.…”