Nineteen patients with non-Hodgkin lymphoma of unfavourable histology (15 high grade and 4 intermediate grade) were treated with two new combination chemotherapeutic schemes. Except for one all were partial (8) or complete (10) responders to treatment. Polyamines were measured in every spontaneously voided urine sample. Pretherapeutically all (11) stage III and IV patients had borderline or increased urinary putrescine (Pu) and sum of isoputreanine, spermidine and spermine (sigma Isoputr,Sd,Sp), except for the non-responder. Except for one, all (8) stage I and II patients had normal urinary Pu and sigma Isoputr,Sd,Sp. Posttherapeutically patients with pretherapeutically increased sigma Isoputr,Sd,Sp returned to normal (5), borderline (2), or slightly increased (3) levels. The post-therapeutic achievement of normal or borderline sigma Isoputr,Sd,Sp was not necessarily connected with accomplishment of complete remission. From the start of therapy until clinical restaging, partially or completely responding stage III and IV patients excreted 5-234 mmol sigma Isoputr,Sd,Sp per mol of creatinine above the mean normal value plus 2 SD. For stage I and II patients and the clinical non-responder this parameter amounted to 0-5 mmol/mol of creatinine. Peaks in urinary Pu and sigma Isoputr,Sd,Sp follow-up curves were related in time to the administration of chemotherapeutics. For responding stage III and IV patients the rate of the decrease of sigma Isoputr,Sd,Sp levels paralleled the clinically observed rate of tumour load reduction. This study suggests that notably for non-Hodgkin lymphoma patients with high tumour loads the constant monitoring of polyamines can provide information on pretherapeutic spontaneous tumour cell loss, the efficacy of chemotherapeutic combinations, the kinetics-, and (within certain limitations) the extent of therapeutically induced tumour cell death.