Tumour site and renal dysfunction as factors influencing leucopenia after chemotherapy for Burkitt's lymphoma.

Forty-four (44) patients with Burkitt's lymphoma received identical combination chemotherapy on the basis of body surface area. Patients with renal dysfunction, more common in those with abdominal tumours, were at significantly greater risk of developing severe leucopenia (less than 1000 cells/dl) than those with normal renal function (P less than 0.0001). Similar results were seen in a series of 8 patients with normal marrows treated with only i.v. cyclophosphamide and intrathecal methotrexate. Giving a lower initial dose of cyclophosphamide seemed to reduce the risk of severe leucopenia in 5 additional patients with evidence of renal dysfunction. The mechanism is postulated as delayed excretion of the active metabolites of cyclophosphamide. Adjustment of the chemotherapeutic dose should be considered when treating patients with renal dysfunction.