Pancreatic serous cystadenomas have a low malignancy rate. When nonsymptomatic, in selected patients, they can be managed without surgery; however, a high degree of diagnostic reliability is crucial. We admitted 100 consecutive cases (87 women with a median age of 51.86 years). Of these, 44 were symptomatic and 56 were diagnosed incidentally. Ultrasound correctly diagnosed 53% of the cases, incorrectly 31%, and was nondiagnostic in 16%. Computed tomography scan had similar rates (54%, 34% and 12%, respectively), while magnetic resonance imaging improved diagnostic accuracy to 74% and reduced incorrect diagnoses to 26%. In 21 cases, exploratory needle aspiration of the cyst was carried out; only 8 samples (38%) resulted in a diagnosis; in 12 patients (57%) insufficient material was acquired to allow for diagnosis, one case demonstrated epithelial dysplasia. In 1 patient an exploratory puncture resulted in a very serious bleeding. Sixty-eight patients were treated surgically, the 44 symptomatic cases and another 24 patients with ill-defined oligocystic lesions that could not be differentiated as serous or mucinous in the preoperative period. Two patients underwent resection because of frank tumor growth. In the two time periods analyzed (the first 7 years and the subsequent 6.5 years) the relationship between cases observed/operated on did not significantly change. Twenty-one (30.8%) distal pancreatectomies, 14 (20.5%) intermediate resections, 10 (14.7%) pancreaticoduodenectomies 4 (5.8%) enucleations, and 1 (1.4%) duodenum-preserving pancreatic head resection were carried out. Nine patients (13.2%), underwent exploratory laparotomy with a diagnostic biopsy. Another 9 underwent decompressive interventions with cystojejunostomies. The morbidity was 27.9%, with a reoperation rate of 7.3% and zero mortality. In general the patient's pain resolved in the postoperative period. Median follow-up was 43 months (range, 4-191 months). One patient died from other causes, and all others are currently alive. In the group of 32 patients who did not undergo operation, the median follow-up is 69 months (range, 8-164 months). Until more sophisticated technologies can be developed, the current diagnostic work-up will not result in increased preoperative diagnosis of serous-cystic tumors of the pancreas. This is mainly relevant to the oligocystic forms, which account for about one fourth of all serous tumors observed.