We investigated the total, free, and acetylated polyamine concentrations in pancreatic tissue, serum, and urine of 20 patients with pancreatic cancer, 30 healthy volunteers, and 40 patients with nonmalignant, gastrointestinal diseases by reversed-phase liquid chromatography. Tissue concentrations in carcinoma compared to histologically unaffected pancreas were significantly higher for putrescine, elevated for cadaverine, and nearly identical for spermidine and spermine, while N1-acetylspermidine was detectable in cancer tissue only. With the exception of free spermine in urine and total spermine in serum, all other polyamines were significantly elevated in the urine and serum of cancer patients compared to healthy controls. These data support the concept that polyamines play an important role in rapidly growing tissues. However, nonmalignant gastrointestinal diseases partly showed similar elevations. Because of this low specificity, polyamines are of little value only as diagnostic markers of pancreatic carcinoma. Since polyamine concentrations normalized in patients after curative operation while they were further elevated in patients with tumor relapse or metastases, polyamines might play a clinical role in predicting therapeutic success or indicating relapse of the tumor. A significant linear correlation of polyamine concentrations and the size of the tumor was found while a significant correlation to CEA, CA 19-9, and CA 125 or the presence of organ metastases did not exist.