The influence of relative body weight on toxicity of combination chemotherapy with cisplatin and etoposide

Abstract

Purpose: This study was conducted to determine whether there was any relationship between the adverse toxicity of combination chemotherapy and clinical values including age, sex, creatinine clearance (Ccr), body surface area and relative body weight. Methods: Cisplatin at a dose of 80 mg/m² on day 1 and etoposide at a dose of 100 mg/m² on days 1, 2 and 3 were given to 42 consecutive patients with solid tumors. All patients had normal major organ function and received uniform hydration therapy. Results: Body Mass Index as a measure of relative body weight was inversely correlated with the percentage decrease in white blood cells (P = 0.0681) and platelet count (P = 0.0115). Body surface area was also inversely correlated with leukopenia (P = 0.0171) and thrombocytopenia (P = 0.0058). In contrast, age, sex and Ccr had no significant relationship with adverse toxicity. Conclusions: It is concluded that dose adjustment of combination chemotherapy with cisplatin and etoposide according to age or ideal body weight is not appropriate and that a conventional dose modification method based solely on body surface area is probably not sufficient to reduce interpatient variability of cancer chemotherapy. A pharmacokinetic and pharmacodynamic study of combination chemotherapy is warranted to establish the ideal dose modification method.