PROBABILITY OF LONG-TERM DISEASE-FREE SURVIVAL FOR ACUTE MYELOID-LEUKEMIA PATIENTS AFTER FIRST RELAPSE - A SINGLE-CENTER EXPERIENCE

Background: Various polichemotherapy regimens, including either high- or intermediate-dose Ara-C, are generally utilized to reinduce remissi on in relapsed AML patients. After achieving second CR, bone marrow tr ansplantation (either allogeneic or autologous) represents the treatme nt of choice for eligible patients, with the aim of prolonging remissi on duration and improving disease-free survival. Patients and methods: fifty AML patients in first hematological relapse were treated with M EC regimen, consisting of a 6-day induction cycle [mitoxantrone 6 mg/m (2)/day, cytarabine (Ara-C) 1 g/m(2)/day and VP-16 80 mg/m(2)/day] fol lowed by a if-day cycle with the same drugs for patients achieving com plete remission (CR); allogeneic or autologous bone marrow transplanta tion (BMT) were planned as post-consolidation treatment. Results: Thir ty-four patients (68%) achieved second CR, 3 (6%) died during inductio n and 13 were refractory. CR rate was significantly higher in patients with a first CR lasting >6 months (82% vs. 41%, P < 0.001). Out of th e 34 patients in CR after the 4-day cycle, 18 (53%) were not eligible to transplant and did not receive any further therapy and 16 (47%) rec eived autologous (15 cases) or allogeneic (1 case) BMT at a median tim e of 2 months from second CR. Twenty-two patients relapsed after a med ian time of 6 months (range 1-31), 1 patient died from transplant-rela ted toxicity and 11 are in continuous CR [7 out of 16 (44%) in the tra nsplanted and 4 out of 11 (36%) in the non-transplanted group]. Overal l survival and event-free survival for the 50 patients were 29% and 19 % at 70 months, respectively. The disease-free survival for the 34 pat ients who obtained second CR is 29% projected at 69 months [41% at 69 months for 16 transplanted patients versus 18% at 49 months for the re maining 18 patients (P = 0.007)]. Conclusions: These results show that MEC followed by high-dose post-consolidation treatment is a promising approach in relapsed AML; however, alternative strategies are to be i nvestigated for the relevant fraction of patients that, even achieving second CR, are not eligible for BMT.