Evaluation of Pancreatic Exocrine Function in Patients With Intraductal Papillary Mucinous Neoplasm (IPMN) of the Pancreas

Pathological and radiological findings of Intraductal Papillary Mucinous Neoplasm (IPMN) are characterized by acinar and duct alterations, probably responsible for a significant impairment of exocrine function. Similar alterations are present in chronic pancreatitis and in the pathological process of aging in which a certain degree of pancreatic exocrine insufficiency (PEI) has been demonstrated. These changes may be responsible for malabsorption and specific nutritional deficiency and thus prompt enzyme replacement therapy. Until now these aspects of IPMN have scarcely been taken into account. The aim of this study was the evaluation of pancreatic exocrine insufficiency (PEI) in patients with stable IPMN (Main Duct, Branch Duct and combined) with evidence of a wide spread involvement of the pancreatic gland. Eighty-nine patients with magnetic resonance cholangiopancreatography (MRCP) findings of cystic lesions compatible with IPMN were evaluated. Patients with other possible causes of PEI (pancreatic or gastric resection, diabetes mellitus, inflammatory bowel disease and celiac disease, etc.) were excluded. Twentysix patients with 3 or more cystic lesions were enrolled and followed up for at least 1 year. Exocrine pancreatic function was evaluated by determination of fecal elastase-1 (FE-1). A five degree radiological score system, based on MRCP, was specifically created to judge glandular involvement . The Pearson test was used to correlate FE-1 values with age. The Spearman test was used to correlate FE-1 with the radiological score. The ANOVA test was used to evaluate mean FE-1 values for each involvement degree. Statistical significance was set at p<0.05. MeanFE-1 values were 539.4±111.5µg/g. FE-1 was inversely related to age (r=-0.465; p=0.017) and to radiological score system (rs=-0.478; p=0.013). Mean FE-1 values, adjusted for age, were significantly lower in patients with more severe glandular involvement, such as pancreatic atrophy and main ductor combined type (degree4-5), than in patients with a mild to moderate degree (different degrees of impairment by BD-IPMN; degree1, 2 and 3) (p=0.003). Patients with more severe glandular involvement, such as pancreatic atrophy and main ductectasia, have lower value so fFE-1. Further studies on a larger number of patients with a high degree of IPMN glandular involvement could identify different conditions of PEI.