A retrospective study of 101 patients whose final diagnosis was chronic pancreatitis (N = 40) or pancreatic cancer (N = 61) aimed to test the respective values of clinical symptoms, laboratory tests, ultrasonography, computerized tomography and endoscopic retrograde cholangiopancreatography for screening of pancreatic lesions and for differential diagnosis. The diagnosis of chronic pancreatitis was found uncertain or erroneous in 7 out of the 40 patients and the diagnosis of pancreatic cancer in 10 out of the 61 patients. The difficulties of differential diagnosis were related to three factors: clinical presentation of some cancers resembling that of chronic pancreatitis, presence of pancreatitic calcifications in some cancers and misinterpretation of pancreatic cavities as cysts or as tumour necroses.