RESUMEN
To elucidate factors contributing to the effectiveness of allogeneic hematopoietic stem cell transplantation (alloHCT) in high-risk CLL, immune interventions, GvHD and clinical outcome of 77 consecutive patients allografted for CLL were analyzed. Immune modulation (immunosuppression tapering, rituximab-augmented donor lymphocyte infusions) was guided by minimal residual disease (MRD) monitoring and commenced at a median of 91 (22-273) days after alloHCT, resulting in a probability of being event free and MRD-negative 1 year after transplant of 57% (84% in those encountering chronic GvHD). Patients who were event free and MRD-negative at the 12-month landmark had a 4-year PFS of 77% and largely remained durably MRD-negative if MRD clearance had occurred subsequent to immune modulation. Three-year overall survival, PFS, relapse incidence and non-relapse mortality of all 77 patients were 69, 57, 26 and 24%, respectively. Survival was not affected by EBMT risk category but by active disease at alloHCT, which could not be overcome by intensification of conditioning. Twenty-three patients who experienced relapse post alloHCT had a survival of 56% at 2 years after CLL recurrence. In conclusion, MRD-guided immune modulation after alloHCT for high-risk CLL can provide durable MRD clearance in more than half of the patients.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia Linfocítica Crónica de Células B/terapia , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Adulto , Anciano , Erradicación de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Recurrencia , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: In a single-center retrospective donor versus no-donor comparison, we investigated if allogeneic stem cell transplantation (alloSCT) can improve the dismal course of poor-risk chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: All patients with CLL who were referred for evaluation of alloSCT within a 7-year time frame and had a donor search indication according to the EBMT criteria or because of Richter's transformation were included. Patients for whom a matched donor could be found within 3 months (matches) were compared with patients without such a donor (controls). Primary end point was overall survival measured from the 3-month landmark after search initiation. RESULTS: Of 105 patients with donor search, 97 (matches 83; controls 14) were assessable at the 3-month landmark. Matches and controls were comparable for age, gender, time from diagnosis, number of previous regimens, and remission status. Disregarding if alloSCT was actually carried out or not, survival from the 3-month landmark was significantly better in matches versus controls [hazard ratio 0.38, 95% confidence interval (CI) 0.17-0.85; P = 0.014]. The survival benefit of matches remained significant on multivariate analysis. CONCLUSION: This study provides first comparative evidence that alloSCT may have the potential to improve the natural course of poor-risk CLL as defined by the EBMT criteria.