[Prognostication of hematotoxicity for radio- and chemotherapy in patients with breast cancer].

The effectiveness of radiation and chemotherapy for breast cancer depends on individual response to drug-induced toxicity. The response can be evaluated by means of myelodepression. To this end, changes in leukocyte DNA level after ex vivo gamma radiation test were used as a criterion. Patients, aged 29-78, with tumors stage IIIB-IV received standard radiotherapy (50 Gy) or cyclophosphamide-methotrexate-5-fluorouracil (CMF). Clodronate alone was given to 26 patients and prior to a CMF course. The method proved prognostically effective since it revealed a significant inverse relationship between S-index and leukocyte nadir for both modalities. However, chemotherapy resulted in more pronounced leukopenia. With clodronate administration, the correlation was not significant. When clodronate was supplemented with CMF chemotherapy involved a significant relationship was observed between the two factors.