Cystic lesions of the pancreas are being diagnosed with increasing frequency,covering a vast spectrum from benign to malignant and invasive lesions.Numerous investigations can be done to discriminate between benign and non-evolutive lesions from those that require surgery.At the moment,there is no single test that will allow a correct diagnosis in all cases.Endoscopic ultrasound(EUS) morphology,cyst fluid analysis and cytohistology with EUS-guided fine needle aspiration can aid in this difficult diagnosis. Cystic lesions of the pancreas are being diagnosed with increasing frequency, covering a vast spectrum from benign to malignant and invasive lesions. Numerous investigations can be done to discriminate between benign and non-evolutive lesions from those that require surgery. At the moment, there is no single test that will allow a correct diagnosis in all cases. Endoscopic ultrasound (EUS) morphology, cyst fluid analysis and cytohistology with EUS-guided fine needle aspiration can aid in this difficult diagnosis.