Prevalence and Outcomes of Cystic Neoplasm of the Pancreas in Immunosuppressed Patients With Solid Organ Transplantation

Abstract

Introduction: To determine the prevalence of incidental pancreatic cystic neoplasms (PCNs) in solid organ transplant (SOT) recipients and describe the clinical course of these lesions in patients on chronic immunosuppressive therapy after transplantation. Methods: Using organ transplant databases at Mayo Clinic Florida, we retrospectively reviewed medical records of all patients who received a SOT between 2000 and 2013. Records of cross-sectional abdominal imaging were searched for the diagnosis of pancreatic cyst(s). We also reviewed radiographic imaging to confirm the presence of PCNs. The “worrisome features” were defined as: main pancreatic duct (MPD) involvement (dilation >6 mm), mural nodule, abrupt change in the MPD caliber with distal pancreatic atrophy. The characteristics of the PCN at the initial and follow-up imaging were compared. Cyst size was considered to have changed if there was a difference of ≥5 mm. Results: Of 3,188 patients, 11.4% (n=356) had at least 1 incidental PCN detected on imaging. The prevalence of PCN increased with age; was more common in females (14.7%) than in males (9.7%); and more common in liver transplant recipients (14.9%) as compared to kidney (5%), lung (3%), and heart (6%) transplant patients. The median diameter of the largest pancreatic cyst was 7.0 mm (range: 1-31) and in 6.8% of patients, the cysts were ≥2 cm. Two patients (0.5%) had worrisome features at the time of pancreatic cyst diagnosis. One patient who had a mural nodule at the time of cyst diagnosis had no evidence of malignant transformation after 71 months of follow-up. One patient with branch duct intraductal papillary mucinous neoplasms (IPMN) and MPD involvement died of a non-pancreatic related cause 2 months after the cyst diagnosis. In a cohort of 155 patients with follow-up examination (median follow-up of 39 months), only 2 patients (1.3%) developed worrisome features on follow-up imaging. One case with a newly developed mural nodule underwent pancreatic surgery, with a pathologic diagnosis of high-grade dysplasia. One case with progressive MPD dilatation noted during the follow-up did not undergo surgical resection due to multiple comorbidities. The majority (83%) of pancreatic cysts evaluated at follow-up were either unchanged or smaller in size. Although 16% of patients had increased cyst size during follow-up, none of them developed malignancy or had pancreatic-related morbidity. Conclusion: PCNs are common in SOT recipients. In PCN without high-risk features, the development of features worrisome for cancer is a rare event. Therefore, PCNs can be managed conservatively and their presence should not affect patients’ eligibility for transplant.