EFFECTS OF A MODIFIED CMF TREATMENT (CYCLOPHOSPHAMIDE, METHOTREXATE AND 5-FLUOROURACIL) ON HEMATOPOIETIC TISSUES AND YOSHIDA SARCOMA IN RATS

Effects of a modified CMF treatment on hematopoietic tissue and an imp lanted tumor were studied in rats. The modification of the treatment r efers to the application of cyclophosphamide 24 h after methotrexate a nd 5-fluorouracil. The study was done on Wistar rats bearing Yoshida s arcoma in the ascites form. The controls were a) untreated animals bea ring the tumor or b) treated conventionally with the 3 cytostatics and c) tumor-free animals under either conventional treatment or d) modif ied treatment. We examined survival, the appearance of metastases, and the regeneration of hematopoietic tissues. Improved survival, the abs ence of metastases, and improved regeneration of hematopoietic tissues was observed when modified CMF treatment was applied. These results s upport the importance of sequencing cytostatic protocols for basic hem atological determinants and anti-tumor activity.