Progression of Intraductal Papillary Mucinous Neoplasms of the Pancreas After Liver Transplantation.

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are the most commonly identified pancreatic cystic neoplasms. Incidentally detected IPMNs are common among liver transplant recipients. The risk of IPMN progression to pancreatic cancer in transplant recipients and the impact of immunosuppression on the risk of malignant transformation of IPMN are unclear.

METHODS

In this retrospective study of consecutive liver transplant recipients across Mayo Clinic over a 13-year period, patients were assessed for possible IPMN by automated chart review. Pancreatic cystic lesions were characterized as suspected IPMNs based on imaging criteria. Cox proportional hazards models were used to determine the association between IPMN progression (the development of cancer or worrisome features) and clinical and immunosuppression regimen characteristics.

RESULTS

Of 146 patients with suspected IPMNs, progression occurred in 7 patients (2 cases of IPMN-associated cancer and 5 cases of worrisome features) over an average follow-up of 66.6 months. Immunosuppression type, medication number, and tacrolimus trough levels were not associated with IPMN progression (p > 0.05). Combined kidney and liver transplantation (p = 0.005) and pretransplant cholangiocarcinoma (p = 0.012) were associated with IPMN progression.

CONCLUSION

IPMN progression is rare after liver transplantation even over an extended follow-up period. The findings were notable for the absence of an association between IPMN progression and immunosuppression regimen. Larger studies are needed given the low incidence.