Severe cisplatin (CP)-induced anaemia significantly impairs the patient's quality of life. Prevention based on erythropoietin (EPO) administration would be cost-effective providing that individual predictive factors of anaemia are identified. The aim of the present study was to identify parameters able to predict the occurrence of CP-related anaemia. This prospective study was conducted on 40 head and neck cancer patients receiving a CP (100 mg/m(2), intravenous (i. v.) on day 1) - 5-fluorouracil (5-FU, 1 g/m(2)/dx5 days by continuous infusion) induction chemotherapy. Three cycles were given at 3-weekly intervals. Platinum pharmacokinetics (total and ultrafilterable plasma platinum concentration measured 16 h after CP administration) and 5-FU pharmacokinetics (full-cycle plasma area under the curve, (AUC(0-105h)30 g/l) occurred in 15 patients (38%) and 3 of them also received a blood transfusion. Patient age, 5-FU AUC(0-105h) and total platinum concentration were unrelated to Hb loss. In contrast, ultrafilterable (UF) platinum concentration was significantly correlated to Hb loss: the higher the UF platinum concentration, the greater the Hb loss (P=0.015). A discriminant analysis allowed a cut-off value for UF platinum to be proposed to identify patients developing significant loss of Hb: 91% of patients exhibiting a UF platinum concentration above 50 ng/ml developed significant loss of Hb in contrast to 18% in the group of patients with a UF platinum concentration below 50 ng/ml (odds ratio (95% confidence interval, CI) of 46 (4.7-446)). In conclusion, the present platinum pharmacokinetic survey may be proposed as a valuable approach to identify patients at risk for developing severe anaemia.