Pancreatic cysts: Diagnostic accuracy and risk of inappropriate resections

Pancreatic cystic neoplasms (PCN) frequently undergo surgery, given malignant potential. Pancreatic cyst surgery is associated with significant rates of morbidity and mortality. It is crucial to accurately characterize these lesions pre-operatively to avoid unnecessary surgery in patients with benign pancreatic cysts.

We aimed to assess the correlation between pre-operative (pre-op) diagnosis based on imaging and clinical presentation, and post-operative (post-op) diagnosis based on histopathology in patients undergone pancreatic cyst surgery.

From January 2000 to January 2012, we randomly selected 2000 patients with ICD-9 code 211.6 and 577.2. Amongst these we identified 281 patients undergone pancreas surgery. Patients with no pre-op imaging or non-cyst indication for surgery were excluded (n = 107). Imaging details, demographics, pre-operative physician diagnosis and histopathologic details of pancreatic cysts were recorded in 174 patients.

There was a discrepancy between the pre- and post-operative pancreatic cyst diagnosis in 54 (31%) patients. There was no difference in the proportion of various imaging studies (CT, EUS or MRI) between patients with a correct and patients with an incorrect pre-op diagnosis. The pre-op diagnosis was confirmed at pathology in 87.5% of the presumed SCNs, in 80% of the presumed pseudocysts, in 73.3% of the presumed BD-IPMNs, in 66.7% of the presumed MD/mixed-IPMNs and in 53.6% of the presumed MCNs. The accuracy of the pre-operative diagnosis of presumed MCN was significantly lower compared to the non-MCN cysts (53.6% vs. 75%; p = 0.037). Fourteen percent of resections were performed for asymptomatic benign cysts, preoperatively suspected to be potentially pre-malignant cysts.

In nearly 1 out of 3 patients undergone pancreas cyst surgery, there is a discrepancy between pre- and post-op diagnosis. Pre-op diagnosis of presumed MCN is more likely to be incorrect, compared to the other cysts.