Cyclophosphamide induces more chromosome damage than chlorambucil in patients with connective tissue diseases

The potential for damaging chromosomes of the powerful and widely-used immunosuppressive agent cyclophosphamide has been tested by measuring sister chromatid exchanges in blood lymphocytes of patients with connective tissue diseases. This agent induces more chromosome damage than chlorambucil emphasising the need for sensitive means of predicting patients at particular risk of drug-induced malignant disease.