Assessment of Risk Factors for Mucinous Pancreatic Cysts

Abstract

Background: Mucinous pancreatic cysts, including mucinous cystic neoplasms (MCN) and intraductal mucinous cystic neoplasms (IPMN), are important to diagnose given malignant potential. Little is known about risk factors associated with mucinous cysts. The primary aim of this study was to determine if certain risk factors are associated with mucinous pancreatic cysts. Methods: In an IRB-approved study, patients with pancreatic cysts were identified by searching both radiology and endoscopy databases of abdominal CT, MRI or US from 1995-2006, and EUS procedures from 2000-2006. Clinical records were reviewed, including demographics, results of EUS-FNA (morphology, CEA, cytology) and pathology in cases of surgical resection. Cysts were classified as non-mucinous if EUS-FNA and/or pathology were consistent with a simple cyst, serous cystadenoma or pseudocyst. Cysts were classified as mucinous if EUS-FNA and/or pathology were consistent with a MCN or IPMN. Patients were then contacted by phone, provided informed consent and then were asked to answer questions regarding potential risk factors, including smoking, alcohol, presence of symptoms, diabetes, pancreatitis, personal or family history of cancer and, for females, menstrual history and use of exogenous estrogens. Patients were excluded if they were unable to be contacted or did not wish to participate. Dichotomous risk factors were analyzed using Fisher exact tests with reporting of 2-sided p-values. Continuous risk factors were analyzed using univariate and multivariate unconditional logistic regression. Results: 93 patients (59 females, mean age 63) were included. 41 cysts were categorized as mucinous. Mucinous cysts were more common in patients >50 years (49%) compared to younger patients (19%) (p < 0.05) with an OR of 4.1 (95% CI: 1-24). Mucinous cysts were less common in obese (BMI > 30) patients (27%) compared to non-obese patients (52%) (p < 0.05) with an OR of 0.35 (95% CI: 0.1-1.0). After adjusting for age, BMI was not significant. All other risk factors were not associated with a higher risk for mucinous cysts. Conclusions: Older age appears to be a significant risk factor for mucinous pancreatic cysts and should prompt a more aggressive approach to exclude this diagnosis. Patients with mucinous cysts were less likely to be obese; however this effect was not seen after controlling for age. Smoking, alcohol use, symptoms, pancreatitis, diabetes, personal or family history of cancer, estrogen use or menstrual history appear not to be risk factors for mucinous cysts.