Hematopoietic stem cell transplantation for infantile osteopetrosis.

We report the international experience in outcomes after related and unrelated hematopoietic transplantation for infantile osteopetrosis in 193 patients. Thirty-four percent of transplants used grafts from HLA-matched siblings, 13% from HLA-mismatched relatives, 12% from HLA-matched, and 41% from HLA-mismatched unrelated donors. The median age at transplantation was 12 months. Busulfan and cyclophosphamide was the most common conditioning regimen. Long-term survival was higher after HLA-matched sibling compared to alternative donor transplantation. There were no differences in survival after HLA-mismatched related, HLA-matched unrelated, or mismatched unrelated donor transplantation. The 5- and 10-year probabilities of survival were 62% and 62% after HLA-matched sibling and 42% and 39% after alternative donor transplantation (P = .01 and P = .002, respectively). Graft failure was the most common cause of death, accounting for 50% of deaths after HLA-matched sibling and 43% of deaths after alternative donor transplantation. The day-28 incidence of neutrophil recovery was 66% after HLA-matched sibling and 61% after alternative donor transplantation (P = .49). The median age of surviving patients is 7 years. Of evaluable surviving patients, 70% are visually impaired; 10% have impaired hearing and gross motor delay. Nevertheless, 65% reported performance scores of 90 or 100, and in 17%, a score of 80 at last contact. Most survivors >5 years are attending mainstream or specialized schools. Rates of veno-occlusive disease and interstitial pneumonitis were high at 20%. Though allogeneic transplantation results in long-term survival with acceptable social function, strategies to lower graft failure and hepatic and pulmonary toxicity are urgently needed.

Second Allogeneic Hematopoietic Cell Transplantation for Patients with Fanconi Anemia and Bone Marrow Failure.

A second allogeneic hematopoietic cell transplantation (HCT) is the sole salvage option for individuals who develop graft failure after their first HCT. Data on outcomes after second HCT in patients with Fanconi anemia (FA) are scarce. Here we report outcomes after second allogeneic HCT for FA (n = 81). The indication for second HCT was graft failure after the first HCT. Transplantations were performed between 1990 and 2012. The timing of the second HCT predicted subsequent graft failure and survival. Graft failure was high when the second HCT was performed less than 3 months from the first. The 3-month probability of graft failure was 69% when the interval between the first HCT and second HCT was less than 3 months, compared with 23% when the interval was longer (P < .001). Consequently, the 1-year survival rate was substantially lower when the interval between the first and second HCTs was less than 3 months compared with longer (23% vs 58%; P = .001). The corresponding 5-year probability of survival was 16% and 45%, respectively (P = .006). Taken together, these data suggest that fewer than one-half of patients with FA undergoing a second HCT for graft failure are long-term survivors. There is an urgent need to develop strategies to reduce the rate of graft failure after first HCT.

HLA-matched sibling hematopoietic stem cell transplantation for fanconi anemia: comparison of irradiation and nonirradiation containing conditioning regimens.

Related to the underlying DNA repair defect that is the hallmark of Fanconi anemia (FA), preparatory regimen-related toxicities have been obstacles to hematopoietic cell transplantation (HCT). In an attempt to decrease the risk and severity of regimen-related toxicities, nonirradiation regimens have been explored. The aim of this study is to compare outcomes after irradiation and nonirradiation regimens in 148 FA patients and identify risk factors impacting upon HCT outcomes. Hematopoietic recovery, acute and chronic graft-versus-host disease (aGVHD, GVHD), and mortality were similar after irradiation and nonirradiation regimens. In both groups of recipients aged >10 years, prior use of androgens and cytomegalovirus seropositivity in either the donor or recipient were associated with higher mortality. With median follow-ups >5 years, the 5-year probability of overall survival, adjusted for factors impacting overall mortality was 78% and 81% after irradiation and nonirradiation regimens, P = .61. In view of the high risk of cancer and other radiation-related effects on growth and development, these results support the use of nonirradiation preparatory regimens. As the peak time for developing solid tumors after HCT is 8 to 9 years, longer follow-up is required before definitive statements can be made regarding the impact of nonirradiation regimens on cancer risk.

Allogeneic hematopoietic cell transplantation for fanconi anemia in patients with pretransplantation cytogenetic abnormalities, myelodysplastic syndrome, or acute leukemia.

PURPOSE: Allogeneic hematopoietic cell transplantation (HCT) can cure bone marrow failure in patients with Fanconi anemia (FA). Data on outcomes in patients with pretransplantation cytogenetic abnormalities, myelodysplastic syndrome (MDS), or acute leukemia have not been separately analyzed. PATIENTS AND METHODS: We analyzed data on 113 patients with FA with cytogenetic abnormalities (n = 54), MDS (n = 45), or acute leukemia (n = 14) who were reported to the Center for International Blood and Marrow Transplant Research from 1985 to 2007. RESULTS: Neutrophil recovery occurred in 78% and 85% of patients at days 28 and 100, respectively. Day 100 cumulative incidences of acute graft-versus-host disease grades B to D and C to D were 26% (95% CI, 19% to 35%) and 12% (95% CI, 7% to 19%), respectively. Survival probabilities at 1, 3, and 5 years were 64% (95% CI, 55% to 73%), 58% (95% CI, 48% to 67%), and 55% (95% CI, 45% to 64%), respectively. In univariate analysis, younger age was associated with superior 5-year survival (≤ v > 14 years: 69% [95% CI, 57% to 80%] v 39% [95% CI, 26% to 53%], respectively; P = .001). In transplantations from HLA-matched related donors (n = 82), younger patients (≤ v > 14 years: 78% [95% CI, 64% to 90%] v 34% [95% CI, 20% to 50%], respectively; P < .001) and patients with cytogenetic abnormalities only versus MDS/acute leukemia (67% [95% CI, 52% to 81%] v 43% [95% CI, 27% to 59%], respectively; P = .03) had superior 5-year survival. CONCLUSION: Our analysis indicates that long-term survival for patients with FA with cytogenetic abnormalities, MDS, or acute leukemia is achievable. Younger patients and recipients of HLA-matched related donor transplantations who have cytogenetic abnormalities only have the best survival.