Tumour cell death: the probable cause of increased polyamine levels in physiological fluids.

The occurrence of extracellular polyamines in Ehrlich ascites tumour-bearing mice was studied in relation to tumour growth. The concentration of putrescine and spermidine in cell-free ascites fluid and serum was found to increase significantly with increasing tumour mass. Data is presented which suggest that the observed accumulation of extracellular polyamines is a result of a continuous release from dead or dying tumour cells. This observation is consistent with the notion that extracellular polyamines accumulate during tumour growth and following radio- and chemotherapy as a result of tumour cell death, and emphasizes the potential clinical usefulness of the polyamine analysis for evaluating tumor cell kill.