3. 急性転化の立場から

抄録

Complete prevention of blast crisis of CML has never been achieved, and we have attempted to prolong the survival time of CML by the early diagnosis and treatment of blast crisis. First of all, through a retrospective analysis on past 23 cases of CML with blast crisis in our clinic, we decided the following parameters for early diagnosis of blast crisis. Major parameters consisted of (1) rapid reenlargement of the spleen, (2) myeloblasts in peripheral blood (P. B.) and/or bone marrow (B. M.) ≥5%, (3) promyelocytes in P. B. and/or B. M. ≥20%, (4) additional changes in Ph¹ chromosome. Minor parameters consisted of (1) unknown fever of higher than 38°C (2) bleeding tendency (3) neuralgic pain in the lower extremities (4) RBC≤3×10⁶ (5) platelets≤1×10⁵ (6) basophils in the P. B. and/or B. M. ≥20% (7) dry tap in B. M. (8) positive CRP. (9) elevation of NAP-score and (10) extramedullary tumor formation. When any of the following combinations of these parameters are found, the early treatment for blastic crisis has been given immediately. (1) more than 3 majors only, (2) 2 majors plus more than 2 minors, (3) 1 major plus more than 3 minors and (4) more than 5 minors only. Median survival of 22 cases with CML treated early under these criteria was more than 8.3 months, while that of 9 cases treated after developing hiatus leukemicus was 3.7 months.