Concomitant radiotherapy with chemotherapy using carboplatin. Focusing on an analysis of haematological toxicity

Forty-four patients with advanced cancer were treated with concurrent Carboplatin (CBDCA) and conventional radiotherapy (RT). CBDCA was administered weekly throughout the RT course at a dose of 100-200 mg/week as a 1-hour infusion. RT was given with mainly 2.0 Gy or 2.5 Gy fraction 4 days/week to a total dose of 50-70Gy. The total dose of CBDCA administered ranged from 400 mg to 1,200 mg with a mean dose of 813 mg. Thirty-three patients (75%) received the planned treatment without interruption. Grade 3-4 leukopenia was observed in 23% of the cases, Grade 3-4 anemia in 14%, and Grade 3-4 thrombocytopenia in 11%. To reveal what treatment or patient characteristics are related to haematological toxicity, multiple regression analysis was applied. The results of the analysis showed that CBDCA area under the curve (AUC) is predictive of leukopenia and Karnofsky performance status (KPS) is predictive of % decrease of haemoglobin or thrombocyte. When the indications for this treatment are limited to patients with KPS≥80% and AUC≤12mg/ml/min, it is assumed that nearly 90% of the cases can receive the treatment without interruption because of haematological toxicity. (author)