Intensity Hematopoietic Stem Cell Transplantation Research Articles

Effect of aprepitant on intravenous tacrolimus disposition in reduced intensity hematopoietic stem cell transplantation

Effect of aprepitant on intravenous tacrolimus disposition in reduced intensity hematopoietic stem cell transplantation

Effect of aprepitant on intravenous tacrolimus disposition in reduced intensity hematopoietic stem cell transplantation

Aprepitant (AP) is a known inhibitor of cytochrome P450 3A4 which may affect tacrolimus metabolism. We retrospectively examined the effect of oral AP on intravenous tacrolimus concentrations in 26 patients undergoing reduced intensity transplantation from 09/2005 to 09/2006. Oral AP 125 mg daily was administered on transplant day +1 and 80 mg on days +2 and +3. Intravenous tacrolimus was administered as a 0.03 mg/kg/day continuous infusion on day -6 through day +1 (pre-AP), during-AP (days +2 to +7), and post-AP starting on day +8. Tacrolimus doses were adjusted to achieve concentrations of 5-20 ng/mL. Dose-corrected tacrolimus concentrations (ng/mL/mg per dose) in the pre-AP, during-AP, and post-AP time periods were: 8.12 (95% CI: 7.3-9.1), 11.63 (95% CI: 9.63-13.63), and 11.42 (95% CI: 8.12-14.7), respectively (P<0.01 between pre-AP and during-AP, P<0.01 between during-AP and post-AP, P = 0.01 between pre-AP and post-AP time periods). Although statistically significant, the observed rise was not clinically significant between during-AP and post-AP time periods. Previous work has shown that AP is not expected to exert an inhibitory effect within 48 h of AP discontinuation. Collectively, these data suggest that AP effect on tacrolimus metabolism is of minor clinical significance. A controlled trial is needed to confirm these findings.

Persistent Recipient Antigen-Presenting Cells in Human Hematopoietic Stem Cell Transplantation: Identification of a New Dermal Subset That Outlives Epidermal Langerhans Cells.

Graft versus host disease (GVHD), a potentially lethal complication of hematopoietic stem cell transplantation (HSCT), is initiated by recipient antigen presenting cells (APC) priming donor T cells. The skin, a commonly affected organ, contains diverse APC including epidermal Langerhans cells (LC) and heterogeneous dermal dendritic cells (DC) whose phenotype, turnover and contribution to GVHD is not well described. The persistence of LC in mice and to some extent humans, is well known, yet the importance of LC relative to dermal DC in the lichenoid dermal infiltration of GVHD remains unproven. In this study we have:1.analyzed the depletion of dermal APC by conditioning, demonstrating a resistant DR+ CD14+ subset;2.identified a DR+ CD14+ fXIIIa+ dermal cell that remains recipient in origin for up to 1 year post HSCT and may therefore contribute to the sensitization of donor T cells and promotion of GVHD.From 2003 to 2007 we obtained 22 pairs of 2mm skin biopsies pre and post conditioning (high dose BuCy or CyTBI and reduced intensity Flu/Mel) and 85 biopsies at day 40, 100 and 365 post HSCT from patients with sex-mismatched donors. Pre and post conditioning samples were digested with dispase and collagenase followed by single step B–D Trucount analysis with CD45, HLA-DR, CD14 and CD1a antibodies. Chimerism was determined on cytospins of spontaneously migrated dermal APC and collagenase digested dermal cells using sequential four-colour confocal microscopy and X/Y fluorescence in situ hybridization. We find 3 populations of CD45+ DR+ dermal cells: CD14+ CD1a- fXIIIa-; CD14+ CD1a- fXIIIa+; CD1a+ CD14- fXIIIa-. Characterization of these cells in vitro shows that CD14+ cells are more adherent and phagocytic than CD1a+ cells and that the fXIIIa+ component is in addition, heavily granulated with ingested melanin. CD1a+ APC are more sensitive to depletion by conditioning (201 pre /97 post; mean cells per mm2; P 0.03) compared with CD14+ cells (210 pre /213 post; cells per mm2; P 0.86). Both are reduced in HSCT patients compared with controls (706 CD14+ and 468 CD1a+ cells per mm2; both P 0.01), in contrast to LC that are relatively well preserved in HSCT patients. CD1a+ cells are equally sensitive to depletion by both high dose and reduced intensity HSCT. Chimerism analysis at 40, 100 and 365 days post HSCT has shown regimen-dependent but nearly complete donor LC engraftment by 100 days. In dermal cells, two strikingly different patterns of engraftment are seen. CD1a+ and CD14+ fXIIIa- cells, obtained either by migration or digestion, engraft rapidly in all patients, ahead of LC, reaching medians of 99% and 100% donor, respectively, at day 40. In contrast, CD14+ fXIIIa+ cells, which are obtained only from digested dermis, are very slow to engraft in the absence of GHVD, reaching only 63% median donor after high dose and 10% median donor chimerism after reduced regimens, at 1 year. Acute GVHD promotes engraftment with 100% donor chimerism seen in nearly all patients at day 100. Preliminary data indicate that these cells are not actively synthesizing DNA, suggesting a different means of survival compared with persistent recipient LC. In conclusion, we have identified a new subset of human dermal APC with protracted survival after high dose and reduced intensity HSCT, sensitivity to GVHD and potential importance in promoting donor T cell reactivity to host antigens.

Hematopoietic Chimerism in Patients with Hematological Malignancies Treated with Donor Lymphocyte Infusions Combined with IL-2 for Relapse after Allogeneic Stem Cell Transplantation.

Donor lymphocyte infusions (DLI) are considered to be the treatment of choice in pts with relapses after allogeneic hematopoietic stem cell transplantation (HSCT). This kind of treatment is based on alloreactivity of donor lymphocytes, mediating a graft-versus-leukemia (GVL) effect. However, the relapses of acute leukemia in many cases are not susceptible to DLI. There were few reports that the concominant administration of cytokines (IL-2, IFN-alfa) and DLI is more efficient for conversion to complete donor chimerism (CC) from mixed chimerism (MC) and leads to remission in pts relapsed after HSCT, but the significance of this therapy is still not estimated. The aim of study was to evaluate the efficacy of DLI treatment combined with IL-2 i.v. administration for CC establishment and remission induction in pts with relapses after HSCT for hematological malignancies. 26 pts were treated with DLI for relapses after ASCT from related siblings in 2001–2007. 12 of them were included in the study. Median age was 25 y (16–44), 9 men/3 woman, 4 pts with AML, 1 - APL, 1 - ALL, 1 -ANL, 3 -CML, 2- MDS. 2 pt received reduced intensity HSCT, 10- conventional one. Median time to relapse was 12,5 months (3,5 – 48 months).10 pts demonstrated hematological relapses, 1 pt with APL and 1 pt with CML - molecular relapses. All pts with AL in overt relapse received chemotherapy first and then DLI was performed in aplasia. CML pts were treated with Hydrea and Glivec and then DLI were administrated. Median dose of infused DL was 6,34 x 108/kg (median 6 transfusions per pt) with median of CD3+ cells. Chimerism status was investigated on BM and PB using VNTR/STR analysis at relapse, before every DLI and monthly after DLI completion. All pts demonstrated MC in bone marrow before chemotherapy (median 74% of host DNA). 9 pts were still MC after chemotherapy and before DLI (median 38% of host DNA), 3 pts became CC before DLI. In all pts DLI were combined with IL-2 (2–6 MU with every DLI). In 6 pts with MC after chemotherapy only 1 (with CML) became CC after 1 course of DLI and developed aGVHD II–III and then cGVHD. 5 pts (with AL and MDS) after DLI were still MC remaining in hematological remission. One of them died of CMV infection. 2 pts recieved the 2nd course of DLI + IL-2, became CC and are still well and alive (1 - with cGVHD, 1 - without GVHD) for 30 months. For 2 pts (AML) with MC 2nd DLI course was not possible (donor was not available) and they received the course of IL-2 (5 days for 6 MU daily) in 2 months after DLI. The both are in complete remission with CC and cGVHD. 4 pts showed no effect and soon relapsed despite the 2nd DLI course in 2 pt and 2nd course of IL-2 in 1 pt. Despite the small and heterogenious group we may conclude, that DLI administration concomitantly with IL-2 leads to more prominent GVL effect and quick conversion from MC to CC. The interesting observation is that the additional infusions of IL-2 were effective for conversion to CC and remission induction in 3 of 4 pts resistant for DLI.

Risk factors and attributable mortality of late aspergillosis after T‐cell depleted hematopoietic stem cell transplantation

Invasive aspergillosis occurs in 5-15% of allogeneic hematopoietic stem cell transplant (HSCT) recipients. Through the 1990s there has been an increase in the incidence of late aspergillosis (LA). We report on the incidence, risk factors, and attributable mortality of LA in a cohort of 398 adult and pediatric patients at Memorial Sloan-Kettering Cancer Center from January 1999 through December 2003. LA was defined as occurring > 40 days post HSCT. LA cases were identified by prospective surveillance and examination of a computerized database. Probable or definite aspergillosis was defined by standard EORTC/MSG criteria. Mortality was attributed to LA if it caused or significantly contributed to death. The overall incidence of LA in our cohort was 4.1%. Median time from stem cell infusion to diagnosis of LA was 164 days (range 68-677) after HSCT. The incidence of LA among unmodified, T-cell depleted, or reduced intensity HSCT was 2.2%, 4%, and 6.8%, respectively (P not significant). Risk factors for LA were grade II-IV acute graft-versus-host disease (GVHD) (P=0.002), chronic GVHD (P=0.01), secondary neutropenia (P=0.02), and reduced intensity conditioning containing alemtuzumab (P=0.01). LA was the immediate cause of death in 1 of 10 (10%) T-cell depleted, 2 of 2 (100%) unmodified, and 1 of 4 (25%) of reduced-intensity HSCT. LA developed a median 164 days post HSCT. All-cause 30-day mortality of LA was 56.3%. The majority of LA cases died of concurrent infections and not from invasive aspergillosis.

Reduced Intensity Hematopoietic Stem Cell Transplantation for Treatment of Class 3 Lucarelli Severe Thalassemia Patients.

Approximately 80% of children with severe thalassemia (thal) were cured with hematopoietic stem cell transplantation (HSCT). However, initial reports suggested that a subset of patients (pts) had poorer outcomes, and were more likely to experience transplant-related mortality or recurrence. These were older pts who had evidence of organ damage from iron-overload and were classified as class 3 Lucarelli pts. One approach to reduce the mortality that has been tested in limited series is reduced intensity (RI) HSCT, which relies upon immunosuppressive rather than ablative pre-transplantation conditioning to facilitate engraftment of donor cells. We conducted RIHSCT in 8 severe thal pts with class 3 lucarelli. All were older than 10 yrs of age (median 12.5 yrs; range 10 – 18) and received blood more than 100 transfusions. Three pts had homozygous β thalassemia and 4 had β thalassemia/hemoglobin E. Five of these pts had splenectomy. The conditioning regimen; busulfan 12 mg/kg orally, iv. fludarabine 175–180 mg/m2, antithymocyte globulin (ATG) (Fresineus®) 40 mg/kg, was given in all pts. In addition, one pt (pt 2) also received thiotepa 10 mg/kg and single fraction total lymphoid irradiation (TLI) 500 cGY and one (pt 1) also received. TLI. All pts received hydroxyurea 20 mg/kg at least for 6 months prior to transplant in order to suppress erythroid expansion. Seven pts received peripheral blood stem cells (PBSC) from 6 HLA antigens matched siblings and 1 (Pt2) received T cell depleted PBSC by CD34+ selection from 4 HLA antigens matched mother. The median number of infused CD34+ cell was 9 × 106cells/kg (range 6.5 – 15 × 106). GvHD prophylaxis regimen was with cyclosporin or tracolimus and MMF. All pts can achieve full donor engraftment. Median time of neutrophil engraftment was 11 days (range 11– 14), and platelet was 14 days (range 12–24). Two pts did not have neutrophil count less than 0.5 × 109/L and four did not have platelet count less than 20 × 109/L. Four pts did not have acute GvHD, 3 had gr I and 1 had gr II. Only 1 pt had limited chronic GvHD. All pts had no major toxicity except pt 2 who developed CMV retinitis but it was resolved. The 2 yr thal free survival rate is 88% (95%CI: 39 %, 98 %) and the 2 yr overall survival rate is 100%. The median time of follow up was 10 months (range: 3 – 63). Currently, 6 pts had full donor chimerism, one had mixed chimerism and one had graft rejection. We would like to suggest that busulfan, fludarabine, and ATG together is the backbone of RIHSCT conditioning regimen for class 3 lucarelli pts. Since 2 (pt 7 and pt 8) out of three pts who did not have splenectomy prior to transplant, had mixed chimerism and one of these 2 pts finally had graft rejection, we, therefore, plan to add either another agent such as thiotepa or melphalan or TLI in our backbone RIHSCT conditioning regimen for the pts who do not have splenectomy prior to transplant in the future to achieve the sustainable engraftment.Donor chimerism study, Recent outcome, and Follow up timePtDay + 15Day + 30Day + 60Day + 100Recent OutcomeF/U time (months)1MFFFA with F632FFFFA with F473FFFFA with F394FFFFA with F125FFFFA with F86FFFFA with F77FMLLA with L48FFMN/AA with M3M = mixed chimerism, F = full donor chimerism, L = loss of donor chimerism, A = alive, F/U = follow up, N/A = not applicable

Unrelated Donor Nonmyeloablative/Reduced Intensity (NST/RIC) Hematopoietic Stem Cell Transplantation (HCT) for Patients with Relapsed and Refractory Hodgkin's Lymphoma (HL).

Myeloablative allogeneic HCT salvages some patients (pts) with relapsed and refractory HL but has a high treatment-related mortality (TRM). NST/RIC conditioning regimens attempt to lower TRM, in particular after previous autotransplants. We studied the outcomes of 146 patients after unrelated donor (URD) HCT with NST/RIC conditioning for relapsed and refractory HL between 1999 and 2004 reported to the CIBMTR. NST/RIC was defined following established CIBMTR criteria as TBI < 500 cGy, busulfan < 9 mg/kg, melphalan ≤ 150 mg/m2 (RIC) or fludarabine without busulfan/melphalan, TBI = 200 cGy (NST). Median (range) age was 30 yrs (13–53), 69% had a Karnofsky score (KPS) ≥ 90%, 95% patients had ≥ 3 chemo regimens prior to HCT and 89% had undergone prior autotransplant. At transplant 57 (40%) had chemosensitive disease and 74 (51%) were chemoresistant. Conditioning was RIC in 95 (65%) and NST in 51 pts (35%). At a median follow-up of 25 mo (3–64) the probability of day 100 mortality was 18% (95% CI, 12–24%), acute GVHD grade 2–4 was 61% (95% CI, 51–70%), cGVHD at 2 years was 69% (95% CI, 60–77%) and TRM at 2 years was 33% (95% CI, 25–41%). Probability of progression free survival (PFS) was 31% at 1 year and 20% at 2 years. Probability of overall survival (OS) was 56% at 1 year and 38% at 2 years (fig 1). Relapse/progression was rare after 2 years with a plateau in the survival curve. Presence of extranodal disease (relative risk [RR] 2.43, 95% CI, 1.30–4.54, p=0.006) and KPS <90 (RR 3.13, 95% CI, 1.63–6.02, p<0.001) predicted TRM. Extranodal disease (RR 2.18, 95% CI, 1.38–3.42, p<0.001), elevated serum LDH at transplant (RR 1.92, 95% CI, 1.22–3.02, p=0.001) and KPS <90 (RR 2.37, 95% CI, 1.47–3.82, p<0.001) were associated with increased risk of death. The major cause of death (45%) was progressive HL. A comparison group of 38 patients after myeloablative URD HCT between 1996 and 2004 was also analyzed. The myeloablative HCT group did not differ in age, KPS or extranodal disease, but differed in GVHD prophylaxis, previous autologous HCT (74% vs. 89% in NST/RIC, p=0.02) and stem cell source (PBSC 45% vs. 73%, p<0.001). More myeloablative HCT pts (63%) were transplanted before 2003 and a yearly increase in proportion of NST/RIC transplants was seen. Use of donor lymphocyte infusions was similar (13% of myeloablative vs 14% in NST/RIC). There was a lower risk of TRM with NST (RR 0.52, 95% CI, 0.26–1.05) and RIC (RR 0.58, 95% CI, 0.31–1.07) compared to myeloablative HCT that did not reach statistical significance. However, the given sample size had only 49% (RIC) and 39% (NST) power to detect a 20% decrease in the 2 year TRM incidence compared to myeloablative transplants. Intensity of conditioning (myeloablative vs NST vs RIC) did not affect TRM, relapse/progression, PFS and OS or death. Chemosensitivity at transplant did not predict for relapse/progression. URD HCT using NST/RIC is associated with acceptable early TRM and can salvage some heavily pretreated pts with relapsed and refractory HL. [Display omitted]

The Role of Telomerase Activity and Telomere Length in Cellular Sensitivity to DNA Damaging Agents.

Dyskeratosis congenita (DC) is a premature aging syndrome characterized by progressive bone marrow failure, abnormal skin pigmentation and nail dystrophy. We have described an autosomal dominant form of DC (AD DC) in a large three-generation kindred that is due to a mutation in the gene encoding human telomerase RNA (hTR). While telomere shortening is a normal consequence of the aging process, DC patients display extremely short telomeres in many somatic cell types, including hematopoietic cells, and they often suffer from bone marrow failure. Allogeneic hematopoietic stem cell transplant (HSCT) remains the only curative therapy for marrow failure in DC. However, HSCT in DC is generally poorly tolerated and associated with significant morbidity, perhaps as a consequence of increased sensitivity of dividing cells to cytotoxic agents during myeloablative therapy. To test this hypothesis, we characterized lymphocytes from various AD DC patients and age matched controls that had been placed in long term culture following in vitro exposure to irradiation (137Cs) and varying doses of Taxol, Adriamycin, and Etoposide. Cell proliferation and viability were quantified by direct visual counting on a hemocytometer, and flow cytometry was employed to assess apoptosis and cell surface expression of senescent markers. In addition to DC lymphocytes having a decreased proliferative capacity and higher basal apoptotic levels, an increased sensitivity to irradiation, Taxol, Adriamycin, and Etoposide was noted. These results suggest that telomere shortening may be an important factor in determining cellular tolerance to cytotoxic therapy and support the concept of reduced intensity HSCT regimens in both aged individuals and DC patients. Further studies have been initiated to determine whether reconstitution of telomere length in DC cells alters response to cytotoxic agents.

Comparative outcomes of reduced intensity and myeloablative allogeneic hematopoietic stem cell transplantation in patients under 50 with hematologic malignancies

We have conducted a direct comparison of the outcomes of reduced intensity and myeloablative conditioning in younger adults with hematological malignancies<50 yr. One hundred and five patients received transplants from human leukocyte antigen (HLA)-matched donors, via either reduced intensity (n=35) or myeloablative conditioning (n=70). The median ages of the reduced intensity and myeloablative groups were 36 and 33 yr (p=0.014). Neutrophil engraftment (i.e. time to absolute neutrophil count>0.5x10(9)/L) occurred more rapidly in the reduced intensity group (median: 10 d; range: 0-21 d) than in the myeloablative group (median: 18 d; range: 11-38 d; p<0.0001). The incidence of grades 2-4 acute graft-vs.-host disease were similar between the reduced intensity and myeloablative groups, at 17% vs. 24% respectively (p=0.40). The cumulative incidence of day 100 non-relapse mortality was 18% in the reduced intensity group, and 21% in the myeloablative group (p=0.88). The overall two-yr survival rates were 43% in the reduced intensity group, and 35% in the myeloablative group (p=0.72). In conclusion, reduced intensity transplantation yielded outcomes comparable with those of myeloablative transplantation in patients under 50 with hematological malignancies.

Dendritic Cells Recovery and Chimerism after Reduced Intensity Hematopoietic Stem Cell Transplantation.

The circulating dendritic cells (DC) are known to have an immunoregulatory role after allogeneic HSC transplantation, and recipient DC have been shown to be important in the development of GVHD in animal model. We studied the DC chimerism of 21 patients (pts) transplanted with reduced intensity conditioning regimen between January 2004 and August 2005. The blood was sampled at days -1, 15, 28 and 56 after transplantation. A series of 17 control normal bloods were also analyzed. DC were identified as ILT3-expressing cells negative for CD14. These cells were sorted by flow cytometry and chimerism was analyzed by PCR of Short Tandem Repeat motifs. Preliminary experiments showed that at least 500 sorted cells were necessary to perform chimerism analysis. Eight females and 13 males (median of age: 54 yrs; 25–61) were enrolled in the study. Diagnoses were 6 AML, 2 sAML, 1 MDS, 3 ALL, 6 MM, 2 NHL and 1 CML. Fifteen pts had high-risk disease. As conditioning regimen, all but 3 pts received cumulative dose of ATG (Thymoglobulin, Genzyme, Lyon, France) (2.5 mg/kg for sibling and 7.5 mg/kg for MUD), in addition to Busulfan 8 mg/kg and Fludarabine 150mg/m2. Eight pts received stem cells from a 10/10 MUD, 2 pts from 9/10 MUD, and 11 pts from sibling donor. For all but one patient, the stem cell source was blood. CsA alone was used for 11 pts, CsA with methotrexate for 8 pts and CsA with MMF for 2 pts. In the absence of aGVHD, the immunosuppressive therapy was tapered within 4 weeks (after day 28 in sibling donor and after day 90 for MUD). The kinetics of the absolute number of DC showed significantly lower count of circulating DC than in control samples at day -1, and a rapid increase, reaching normal values at day 15 post-transplant while the other leukocytes remained at a low value. To determine the origin of post-transplant blood DC, chimerism was analyzed on sorted DC. From 20 pts DC chimerism at day 15 was of full donor origin for 8 pts, mixed in 10 pts. Two pts had no detectable DC. At day 28 from 18 pts, only 4 pts had mixed chimerism. Of these 4 pts, 3 presented at day 56 a full donor chimerism and one patient died from relapse. For T cells at day 15, only one/17 pt had full donor chimerism, and one had no detectable circulating T cells. At day 28, 7/20 pts had full donor chimerism and one without detectable T cells. Only 2/17 had still mixed chimerism at 3 months. Six out of 21 pts relapsed and 3 died from relapse. Among these 6 pts, all but one reached full donor T cells, 3 had a full donor DC at day 28. Six pts from 21 had grade ≥ 2 aGVHD and 3 died from aGVHD. 7/17 evaluable pts had cGVHD. We didn't found any correlation between DC chimerism and engraftment or relapse. At day 15, the median percentage of recipient DC was lower in pts who developed cGVHD (P<0.017) while it was higher in those with aGVHD (but p not significant). In conclusion, this study demonstrates that the circulating DC pool is rapidly reconstituted from both donor and recipient origins. Thereafter at day 28, donor engraftment of DC became predominant. The median of recipient DC was significantly higher in pts without cGVHD. An analysis on a larger series would be useful to determine if the chimerism in DC could be predictive for cGVHD.

Graft-versus-host disease of the kidney after rapid tapering of cyclosporin following reduced intensity hematopoietic stem cell transplantation

Graft-versus-host disease of the kidney after rapid tapering of cyclosporin following reduced intensity hematopoietic stem cell transplantation

Development of graft-versus-host disease depends upon establishment of complete donor T cell chimerism after T cell depleted, reduced intensity hematopoietic stem cell transplantation

Development of graft-versus-host disease depends upon establishment of complete donor T cell chimerism after T cell depleted, reduced intensity hematopoietic stem cell transplantation

Association of Telomere Length in Dyskeratosis Congenita Lymphocytes with Increased Sensitivity to Radiation and Anti-Mitotic Agents.

Dyskeratosis congenita (DC) is a premature aging syndrome characterized by progressive bone marrow failure, abnormal skin pigmentation and nail dystrophy. We have recently described an autosomal dominant form of DC (AD DC) in a large three-generation kindred that is due to a mutation in the gene encoding human telomerase RNA (hTR). Importantly, we have noted progressive shortening of telomeres in lymphocytes from the most recent generation, correlating with earlier onset of severe cytopenias in some of these patients. While telomere shortening is a normal consequence of the aging process, DC patients display accelerated telomere shortening in many somatic cell types. Allogeneic hematopoietic stem cell transplant (HSCT) remains the only curative therapy for marrow failure in DC. However, HSCT in DC is generally poorly tolerated and associated with significant morbidity, perhaps as a consequence of increased sensitivity of dividing cells to cytotoxic agents. To test this hypothesis, we characterized lymphocytes from nine AD DC patients and age matched controls that had been placed in long term culture following in vitro exposure to irradiation (137Cs) and varying doses of Taxol. Cell proliferation and viability were quantitated by direct visual counting on a hemocytometer, and flow cytometry was employed to assess apoptosis and cell surface expression of senescent markers. CD57 and CD95, markers of cellular senescence and apoptosis, were significantly upregulated on DC T lymphocytes after two weeks in culture relative to controls. In addition to DC lymphocytes having a decreased proliferative capacity, an increased sensitivity to Taxol was noted, with an average decrease of 21% in cell growth relative to similarly treated control cells. This effect was also noted in irradiated DC cells. Finally, DC lymphocytes displayed an increased apoptotic index in the presence of varying doses of Taxol. These results suggest that telomere shortening may be an important factor in determining cellular tolerance to cytotoxic therapy and support the concept of reduced intensity HSCT regimens in both aged individuals and DC patients.

Feasibility of reduced intensity hematopoietic stem cell transplantation from an HLA-matched unrelated donor.

To evaluate the feasibility of reduced intensity stem cell transplantation (RIST) with bone marrow from a matched unrelated donor (MUD), we retrospectively investigated 20 patients with hematological disorders who received RIST in the Tokyo SCT consortium from January 2000 to October 2002. The preparative regimens were fludarabine-based (150-180 mg/m(2), n=18) or cladribine-based (0.77 mg/kg, n=2). To enhance engraftment, antithymocyte globulin (ATG) and 4 or 8 Gy total body irradiation (TBI) were added to these regimens in nine and 11 patients, respectively. GVHD prophylaxis was cyclosporine with or without methotrexate. In all, 19 achieved primary engraftment. Three developed graft failure (one primary, two secondary), and five died of treatment-related mortality within 100 days of transplant. Seven of the 19 patients who achieved initial engraftment developed grade II-IV acute GVHD, and seven of 13 patients who survived >100 days developed chronic GVHD. At a median follow-up of 5.5 months, estimated 1-year overall survival was 35%. Compared with a TBI-containing regimen, an ATG-containing regimen was associated with a high risk of graft failure (30 vs 0%, P=0.0737). This study supports the feasibility of RIST from MUD; however, procedure-related toxicities remain significant in its application to patients.

A test dose of I.V. busulfan (BU) is predictive of the area under the curve (AUC) of a single daily dose of I.V. bu in pediatric patients undergoing a reduced intensity (RI) hematopoietic stem cell transplant (HSCT)

High-dose BU-containing chemotherapy has been used in autologous and allogeneic HSCT. Variations in the PK for oral BU in pediatric patients have resulted in either decreased effect or increased toxicity. The IV formulation eliminates the variability of absorption . A simple method to assess PK AUC of single dose/24hrs of IV BU in pediatric patients is described. Patients who signed informed consent were enrolled. The regimen consisted of test dose of IV BU (0.8mg/kg) as a single dose day -10, Fludarabine 30mg/m2/day on days −10 to −6, followed by BU 3.2 mg per Kg/day on days −5 and −4 and rabbit ATG 2mg/kg on days −4 to −1. Phenytoin prophylaxis was given for 4 days. Cells were infused on day 0. There were 5 patients with a median age 8.0 (0.5–16 years);. The median weight was 22.6 (range 4.3–45.4) Kg. Patients diagnoses include: Omenn’s syndrome, Neuroblastoma, ALL, CML, and X linked lymphoproliferative disease. Samples were obtained at 2, 4, 8 and 12 hrs and submitted to the Fred Hutchinson Cancer Center for determination of the AUC. An AUC of 800–1200 was targeted for the test dose. The median measured AUC was 1034 (816–1315) uMol∗min; the clearance was 3.1 (2.4–3.9) (ml/min) kg. The target AUC equals the AUC of the test dose multiplied by 4. The dose of 3.2mg/Kg/q24 hrs was administered and the target AUC was 3800–4200. The measured AUC median was 3590 (2307–4097) uMol∗min and the clearance 3.4 (3–4.2)(ml/min)/kg, Dose adjustment of 10% lower dose on days −5, −4 was made on one patient who had a high AUC, the modification resulted in a lower AUC. No instances of hepatic veno-occlusive disease or seizures developed. Neutrophil and platelet engraftment was prompt in 3/3 evaluable patients. Three of the patients have achieved full chimerism. In conclusion, PK of a test dose of 0.8 mg/Kg of IV BU multiplied by 4 appears to be predictive of the PK for a single daily dose of IV BU in pediatric patients undergoing a RI HSCT.

Fatal deep vein thrombosis after allogeneic reduced intensity hematopoietic stem cell transplantation for the treatment of metastatic gastric cancer

A 61-year-old man received reduced intensity stem cell transplantation (RIST) for the treatment of metastatic gastric cancer. The cytoreductive course of RIST was uneventful until day 0, when fever suddenly developed and his performance status deteriorated. Edema developed in the bilateral lower extremities by day 7, which was diagnosed by Doppler ultrasonography as deep vein thrombosis (DVT) involving the femoral veins to the inferior vena cava. While the edema improved with anticoagulation treatment, gastrointestinal graft-versus-host disease (GVHD) followed on day 13. Diarrhea subsided spontaneously, but hypoalbuminemia persisted, with the subsequent development of oliguria and jaundice on day 18. He died of sepsis on day 30, without any evidence of cancer progression. This case demonstrates that DVT is a potentially significant problem following RIST for solid tumors.