Pancreatic cystic lesions: clinical predictors of malignancy in patients undergoing surgery

Despite advances in cross-sectional imaging and the use of molecular markers, distinguishing between benign and malignant cysts remains a clinical challenge.

To identify both preoperative clinical and cyst characteristics at the time of EUS that predict malignancy.

A retrospective analysis was performed on consecutive patients with pancreatic cysts who underwent endoscopic ultrasound (EUS) and surgical resection from May 1996 to December 2007 at a tertiary centre. Clinical history, EUS characteristics, cytology, tumour markers and surgical histology were collected. Predictors of malignancy were determined by univariate and multivariate analysis using logistic regression.

A total of 153 patients underwent a EUS and subsequent surgical intervention.Of the 153 patients, 57 (37%) had a histological diagnosis of malignancy. On univariate analysis, older age (P < 0.001), male gender (P = 0.010), jaundice (P = 0.039), history of other malignancy (P = 0.036), associated mass in cyst (P = 0.004) and malignant cytology (P < 0.001) were found to be associated with malignancy. History of pancreatitis (P = 0.008) and endoscopist impression of pseudocyst (P = 0.001) were found to be associated with benign cysts. Multivariate analysis found that only older age [Odds ratio (OR), 1.04; 95% confidence interval (CI), 1.01-1.08], male gender (OR, 2.26; 95% CI, 1.08-4.73) and malignant cytology (OR, 6.60; 95% CI, 2.02-21.58) were independent predictors of malignancy.

Older age, male gender and malignant cytology from EUS predict malignancy at surgical resection. These characteristics may be used to estimate the probability of malignancy in a cyst and aid in management.