Jacqueline M. Cornish

Unrelated donor bone marrow transplantation for children with relapsed acute lymphoblastic leukaemia in second complete remission

Allogeneic sibling bone marrow transplantation (BMT) is the recommended treatment for relapsed childhood acute lymphoblastic leukaemia (ALL), but appropriate donors are only available in 30% of cases. Unfortunately, BMT from unrelated donors (UD) has been associated with high rates of severe graft‐versus‐host disease (GvHD) and transplant‐related mortality (TRM). In an attempt to improve outcome in UD‐BMT we have assessed the impact of T‐cell depletion using CAMPATH‐1 (anti‐CD52) monoclonal antibodies in 50 consecutively referred patients with relapsed ALL in second remission. All were previously treated according to MRC protocols UKALL X and XI, and then given chemotherapy on MRC R1 from relapse until UD‐BMT. 19 patients had relapsed on and 31 off therapy.

Infections in adults undergoing unrelated donor bone marrow transplantation

This study retrospectively reviews infections over a 7‐year period in 60 consecutive adults (median age 25 years) undergoing their first unrelated donor bone marrow transplant (UD‐BMT). T‐cell depletion was employed in 93%. More than half the patients had one or more severe, potentially life‐threatening, infections. There was a high incidence of invasive fungal infections (Aspergillus 17, Candida four), despite the use of itraconazole or amphotericin prophylaxis. Ten Aspergillus infections occurred beyond 100  d. Two patients (11%) with invasive aspergillosis survived. Clustering of infections was noted, with invasive fungal infections significantly associated with bacteraemias (OR 3.73, P = 0.06) and multiple viral infections (OR 4.25, P = 0.05). There were 21 severe viral infections in 16 patients, with CMV disease occurring in four patients only; viral pneumonitis was predominantly due to ‘community respiratory’ viruses. Most early bacteraemias (68%) were due to Gram‐positive organisms. The majority of episodes of Gram‐negative sepsis were caused by non‐fastidious non‐fermentative bacteria, such as Pseudomonas spp. and Acinetobacterspp., historically regarded as organisms of low pathogenicity. In patients with successful engraftment and minimal graft‐versus‐host disease, late infections suggestive of continued immune dysfunction (shingles, recurrent lower respiratory infections, Salmonella enteritis and extensive warts) were common.

Minimal residual disease status as a predictor of relapse after allogeneic bone marrow transplantation for children with acute lymphoblastic leukaemia.

We have analysed the behaviour of minimal residual disease (MRD) after allogeneic bone marrow transplantation (allo-BMT) in 71 children with acute lymphoblastic leukaemia (ALL). The method relied on PCR of IgH, TCRdelta and/or TCRgamma gene rearrangements followed by electrophoretic size resolution and allele-specific oligoprobing. Patients were similarly conditioned; 55 received marrow from unrelated donors and 16 from related donors. MRD was assessed at various time-points up to 24 months after BMT. Three children were not evaluable due to transplant-related mortality. MRD was detected in 28/32 patients (88%) who relapsed post-BMT; 16 were positive at all times and 12 were initially negative but became positive at a median of 3 months (range 1.5-11) prior to relapse. In contrast, only eight of 36 (22%) patients who remained in continuing complete remission (CCR) (median follow-up 43 months, range 20-94) showed MRD at any time after BMT (P<0.0001). In these eight patients MRD was found up to 9 months after transplant and at low levels (0.01-0.001%). All eight (median follow-up 39 months, range 24-87) had at least two MRD-negative samples tested subsequently and five of the eight had evidence of grade I-II acute graft-versus-host disease (GvHD), raising the possibility of a graft-versus-leukaemia effect. In general, any evidence of MRD after allo-BMT is a poor prognostic sign. However, if immunotherapy were to be targeted towards patients with evidence of persisting MRD after BMT, the method described would expose only a small proportion of patients to unnecessary additional toxicity.

Recent improvement in outcome of unrelated donor transplantation for aplastic anemia

The aim was to determine whether outcome of unrelated donor transplantation for severe aplastic anemia has improved in recent years and whether this is due to patient selection or better transplant technology. We analyzed 498 patients transplanted during 1990–2005. By running univariate regression models dichotomizing year of transplantation we defined 1998 as the year of the most significant change in survival. Five-year survival increased from 32±8% before 1998 to 57±8% after 1998 (P<0.0001). When comparing the cohort before (n=149) and after 1998 (n=349), there were no differences except for older age, and more frequent use of PBSCs, after 1998. High-resolution HLA typing data were unavailable. After 1998, there was less graft failure (11 vs 26%, P<0.0001), less acute GvHD (cumulative incidence 28 vs 37%, P=0.02) and less chronic GvHD (22 vs 38%, P=0.004). In multivariate analyses adjusting for differences in age, HLA-mismatch, performance score and time to transplantation, there was no change in the year of transplant effect (relative risk of death in transplants after 1998: 0.44 (95% confidence interval 0.33–0.59)). There is no evidence for patient selection to explain significantly improved survival in patients transplanted after 1998. We speculate that this is due to better donor matching.

The outcome of children requiring admission to an intensive care unit following bone marrow transplantation

We report the results of a retrospective study of the role of intensive care unit (ICU) admission in the management of 367 children who underwent bone marrow transplantation (BMT) at a tertiary referral institution. 39 patients (11%) required 44 ICU admissions for a median of 6 d. 70% received marrow from unrelated donors, half of which were mismatched; 80% had leukaemia and two‐thirds were considered high‐risk transplants. Respiratory failure was the major reason for admission to ICU. 75% of admissions required mechanical ventilation (for a median of 5 d) and 20 patients had lung injury as defined by the criteria of the Seattle group. None of 11 patients with proven viral pneumonitis survived (P = 0.06) and only one of 20 patients with lung injury survived (P < 0.01). Six of seven patients with a primary neurological problem survived (P < 0.001); these appear to represent a good outcome group. Age, the presence of graft‐versus‐host disease, the use of inotropes, isolated renal or hepatic impairment, and paediatric risk of mortality (PRISM) score were not predictive of outcome. In total, 12 patients (27% of admissions) survived and were discharged from hospital 30 d or more after admission and eight (18%) survived >6 months. ICU admission can be beneficial to selected children post‐BMT but it may be less useful in proven viral pneumonitis. Where mechanical ventilation is required, the duration of this support should be limited unless there is rapid improvement.

Comparison of long-term outcomes after allogeneic hematopoietic stem cell transplantation from matched sibling and unrelated donors

Long-term survivors of hematopoietic stem cell transplants remain at risk of potentially fatal complications that detract from life quality. Long-term morbidity and mortality were compared between matched recipient cohorts surviving 2 or more years and defined by donor type, HLA matched sibling donor (MSD) or volunteer unrelated donor (URD). Patients were previously entered into the prospective multicenter International Unrelated Search and Transplant Study. Thirty-nine centers provided data on 108 URD and 355 MSD recipients surviving more than 2 years. Long-term survival, performance status, chronic GvHD (c-GvHD), secondary malignancy, endocrine dysfunction, cataracts, bone necrosis and dental pathology were compared between cohorts. Twelve year survival was 77±5% for the MSD and 67±11% for the URD cohort (P=0.1). Late death occurred in 105 of 463 recipients alive at 2 years, 73 after 355 (21%) MSD and 32 after 108 (30%) URD transplants, P=0.10. Of 105 deaths, the cause was relapse in 60 and unrelated to relapse in 45 cases. Cumulative incidence of extensive c-GvHD (P=0.002), cataracts (P=0.02) and bone necrosis (P=0.02) was higher after URD transplants. No long-term difference in endocrine dysfunction, secondary malignancy and major dental pathology was detected. This landmark study will assist physicians counseling patients pre-transplant and with their long-term care post transplant.

Second allogeneic bone marrow transplants from unrelated donors for graft failure following initial unrelated donor bone marrow transplantation

Graft failure is a common and severe complication of unrelated donor bone marrow transplantation (UD-BMT). However, there are few reports of a second UD-BMT in this setting. We describe 12 patients with graft failure (five primary, seven secondary) who had a second transplant, five from their original donor and seven from a different donor. Their median age was 9 years. Two patients died before day 10 of regimen-related toxicity. Nine of 10 evaluable patients engrafted in a median of 17 days. Secondary graft failure was seen in one patient. Transplant-related morbidity was significant. Six of nine developed acute GHVD, there were five severe infections and five patients developed Bearman grade 3 or 4 extramedullary toxicity. Overall, five patients survive at a median of 38 months after the second BMT and two are in continuous complete remission. Second transplants from unrelated donors for graft failure can result in prolonged survival.

Unrelated donor bone marrow transplantation in children and young adults with acute myeloid leukaemia in remission

The role of unrelated donor bone marrow transplantation (UD‐BMT) in the management of patients with acute myeloid leukaemia (AML) is uncertain. We describe 18 patients with a median age of 13 years (range 4–31) who received an ex vivo T‐cell‐depleted UD‐BMT for AML (13 in second complete remission (CR2) and five in first complete remission (CR1) with high‐risk features). Nine donor recipient pairs were fully matched; eight of these donor–recipient pairs had a single class I HLA mismatch; one patient had both single class I and class II HLA mismatches. Grade II GVHD of the skin occurred in four patients (22%) and limited chronic GVHD in two patients (11%). There have been four deaths: one from relapse and three from infection. With a median follow‐up of 27 months, 14 patients survive and the actuarial event‐free survival at 2 years is 70 ± 20% (95% confidence interval). We conclude that unrelated donor BMT can result in prolonged disease‐free survival in children and young adults with AML.

Outcome of single fraction total body irradiation-conditioned stem cell transplantation in younger children with malignant disease Comparison with a busulphan-cyclophosphamide regimen

The logistic difficulties of using fractionated total body irradiation (TBI) in the youngest children often limit the choice to single fraction TBI (sfTBI) or non-TBI-based regimens. We retrospectively evaluated 44 such children (<7 years) conditioned with either sfTBI (n=26) or busulphan-cyclophosphamide (Bu-Cy) (n=18), transplanted for hematological malignancies between 1988 and 2001. Both neutrophil and platelet engraftment were faster in the sfTBI group with a similar incidence of graft failure (6.8%). Acute GVHD (graft versus host disease) grade 2–4 occurred in 38.4% and 38.8% and chronic GVHD in 20% and 15.4% of the patients in the sfTBI and Bu-Cy groups, respectively. Grade 2–4 GVHD was associated with reduced risk of relapse (p=0.03). This finding was more pronounced in high-risk patients with 2/10 relapses in patients with GVHD grade 2–4, compared with 13/18 relapses among those with GVHD 0–1 (p=0.05). The probability of overall survival was 43.3% in the sfTBI group and 33.3% in the Bu-Cy group (p=0.6). However, the outcomes for high-risk patients and those with acute lymphoblastic leukemia were better in the sfTBI group. While hypothyroidism, growth hormone deficiency, learning problems and cataract formation were observed only in the sfTBI group, early cardiac toxicity, behavioral problems and seizures were more common in the Bu-Cy group. Thus, where fractionated TBI is not feasible, sfTBI offers improved survival in high-risk children with acute lymphoblastic leukemia compared with Bu-Cy, without an unacceptable increase in early or late toxicity.

Matched and mismatched unrelated donor bone marrow transplantation for juvenile chronic myeloid leukaemia

Juvenile chronic myeloid leukaemia (JCML) is a rare haematological condition of childhood curable only by bone marrow transplantation (BMT). We report our experience using matched and mismatched unrelated donor BMT for JCML in five patients. Although the procedure is hazardous in terms of toxicity and relapse, two patients are alive and disease‐free 28 and 49 months post BMT.