The Role of Interleukin 1 Beta in Differentiating Malignant from Benign Pancreatic Cysts.

Background and Aim: The frequency of detection of pancreatic cystic lesions (PCLs) in magnetic resonance imaging performed for reasons unrelated to the pancreas reaches up to 13.5%. The aim of this study was to evaluate the role of cyst fluid interleukin 1 beta (IL1β) and different endoscopic ultrasound (EUS) features in differentiating premalignant/malignant from benign pancreatic cysts. In addition, to evaluate the role of pancreatic cyst fluid carcinoembryonic antigen (CEA) in differentiating mucinous from nonmucinous pancreatic cysts.

Methods: This study was conducted on 73 patients with PCLs. EUS-guided fine-needle aspiration (EUS-FNA) was performed on all patients. Estimation of IL1β and CEA levels in aspirated specimens were carried out.

Results: Pancreatic cyst fluid IL1β level could not differentiate between premalignant/malignant and benign pancreatic cysts. At a cutoff value of 19.81 ng/mL pancreatic cyst fluid CEA has 64.3% sensitivity and 84.4% specificity in differentiating mucinous from nonmucinous pancreatic cyst. EUS can differentiate between premalignant/malignant pancreatic cysts and benign cysts with a sensitivity of 66.7%, specificity of 69.2%

Conclusions: Pancreatic cyst fluid IL1β level cannot differentiate between premalignant/malignant and benign pancreatic cysts. CEA level can help in differentiation between mucinous and nonmucinous cysts. EUS can be useful in differentiation between premalignant/malignant pancreatic cysts and benign cysts.