Obesity and Fatty Pancreatic Infiltration Are Risk Factors for Pancreatic Precancerous Lesions (PanIN)

Purpose: The roles of intravisceral and subcutaneous fat are unknown and the prevalence of precancerous lesions in obese patients was never evaluated. Aims- To assess the frequency and severity of pancreatic intraepithelial neoplasia (PanIN), to correlate pathological findings with metabolic abnormalities, type of fat and fatty pancreatic infiltration. Experimental Design: Normal pancreatic tissue from surgical specimens was analyzed. Fatty infiltration and fibrosis in intra- and extralobular locations, PanIN were assessed. General characteristics were collected: body mass index (BMI), diabetes and tobacco intake. Liver steatosis, subcutaneous and intravisceral fat were assessed by CT scan (ImageJ software). Results- 110 patients were included (median age: 53.8 [17-85] years). Arterial hypertension, diabetes, tobacco intake were found in 19, 9 and 23%, respectively. Median BMI was 24 [16-37], (BMI<25: 45%, 25-<30: 24%, ≥30: 11%). Overall, PanIN lesions were found in 65% (Type 1, 2 and 3 PanIN in 62, 38 and 1%, respectively). Fibrosis and fatty pancreas (intra- and extralobular locations) were found in 1% and 24% and in 30% and 51%, respectively. A correlation was observed between PanIN lesions and fatty pancreas [extra- (0.01) and intralobular (<0.0001)], intralobular fibrosis (0.003), high BMI (p=0.02), subcutaneous (p=0.02) and intravisceral fat (p=0.02). The number of PanIN lesions was correlated with the intravisceral fat (r=0,22, p=0,04) but not with the subcutaneous fat (r=0.14, p=0.22). In multivariate analysis, PanIN were associated with intralobular fibrosis (OR=5.61 [1.18-42.99]) and the intralobular fat (OR=17.86 [4.935-88.12]). Conclusions: Obesity (android obesity, especially) and pancreatic fatty infiltration are risk factors for pancreatic precancerous lesions.