WHAT DOES ONE DO FOR THE CML PATIENT IN RELAPSE AFTER ALLOGENEIC BONE-MARROW TRANSPLANTATION

The management of CML patients with some evidence of disease after BMT depends on the molecular, cytogenetic and hematological findings of r elapse. Presently, a number of technical and biological problems do no t allow to draw any definitive conclusion on the prognostic significan ce of Minimal Residual Disease detected by PCR. A positive PCR, partic ularly if observed late after BMT, leads to increase the frequency of cytogenetic examinations, but a therapeutic intervention is not justif ied. The criteria to define the cytogenetic relapse are not still esta blished. Therefore it is difficult to interpret the reappearance of Ph -1 chromosome after BMT as disease recurrence invariably progressing t owards the hematological phase. However, alpha-Interferon, donor buffy -coat infusion or their association should be considered in the treatm ent of patients for whom the cytogenetic relapse has been confirmed. T he therapeutic approach to patients with hematological relapse is main ly depending on the phase of disease. The single, sequential or combin ed use of chemotherapy, alpha-IFN, donor buffy-coat infusion and secon d transplant has been shown to be effective in restoring donor hematop oiesis in several patients who relapsed either in chronic or advanced phase. Prospective, randomized, multicentre trials on CML relapse afte r BMT should be planned.