A suspected, but unproved malignant tumor in the head of the pancreas is a fairly common problem for surgeon. Even intraoperatively, differentiation between chronic pancreatitis and carcinoma is difficult. We try to give guidelines about what can be done with a pancreas head mass intraoperatively without previous cytology or histology. When do we have to achieve definite diagnosis at all costs, and how can we achieve it? Results of 40 intraoperative aspiration cytologies, performed for suspected pancreatic cancer were analysed. All of them were controlled by histology in the resected specimen. Intraoperative biopsy was false negative in 12.5% and the diagnosis was uncertain in 35%. These data show that a benign result by itself never excludes the presence of malignancy. If pathology will alter our decision about resection, all efforts should be made to confirm the diagnosis. On the other hand, in a case of a mass lesion with obstructive symptoms, cytology does not alter the need for surgical decompression, and some kind of resection is a reasonable option, even in case of chronic pancreatitis. Nihilistic approach in the case of pancreatic head mass with suspected but unproved malignancy is not justified. Pancreatoduodenectomy should be performed for all tumors even without histologic confirmation if an experienced team can perform it with low postoperative morbidity and mortality.