ALBERT

Description: Administration of kit-ligand (KL) before and after doses of 5-fluorouracil (5-FU) results in marrow failure in mice, presumably because of enhanced KL-induced cycling of stem cells, which makes them more susceptible to the effects of 5-FU. In attempt to capitalize on this effect on stem cells, we studied the ability of KL and 5-FU to allow stable donor engraftment of congenically marked marrow in a C57BL/6 (B6) mouse model. KL was administered subcutaneously at 50 μg/kg, 21 hours and 9 hours before and 3 hours after each of two doses of 5-FU (125 mg/kg) given 7 days apart to B6-recipients. Animals then received three injections of 107 congenic B6-Gpi-1a-donor bone marrow cells at 24, 48, and 72 hours after the second 5-FU dose. A separate group of animals received a single dose of either 1 × 107 or 3 × 107 donor marrow cells 24 hours after the last 5-FU dose. The level of engraftment was measured from Gpi-phenotyping at 1, 3, 6, and 8 months in red blood cells (RBCs) and at 8 months by phenotyping cells from the thymus, spleen, and marrow. Percent donor engraftment in RBCs appeared stable after 6 months. The percent donor engraftment in RBCs at 8 months was significantly higher in KL + 5-FU prepared recipients (33.0 ± 2.7), compared with 5-FU alone (18.5 ± 2.6, P 〈 .0005), or saline controls (17.8 ± 1.7, P 〈 .0001). In an additional experiment, granulocyte colony-stimulating factor (100 μg/dose) was added to a reduced dose of KL (12.5 μg/dose); engraftment was similar to KL alone. At 8 months after transplantation the levels of engraftment in other tissues such as bone marrow, spleen, and thymus correlated well with erythroid engraftment to suggest that multipotent long-term repopulating stem cells had engrafted in these animals. There are concerns for the toxicity of total body irradiation (TBI)- or busulfan-based regimens in young recipients of syngeneic or transduced autologous marrow who are transplanted for correction of genetic disease. In these recipients complete donor engraftment may not be needed. The results with KL and 5-FU are encouraging for the further refinement of non-TBI, nonbusulfan techniques to achieve stable mixed chimerism.

Description: The spatial organization of hematopoietic cell subsets of differing proliferative potential within the bone marrow microenvironment has come under increasing interest. In particular, it has been suggested that hematopoietic stem cells (HSCs) normally reside in a regulatory niche situated at the endosteal bone surface and in close proximity to osteoblasts. In the present study we have investigated how different hematopoietic cell subsets are distributed along a Hoechst dye perfusion gradient that may reflect the distance from marrow blood vessels and the level of oxygenation. C57BL/6J mice were intravenously injected with two doses of Hoechst 33342 at 10 and 5 min before marrow cell harvesting, a period that we determined was insufficient for active dye exclusion in vitro. Flow cytometric analysis revealed a wide distribution of Hoechst staining over 3 logs fluorescence intensity. The cells were then sorted from 6 different regions of the Hoechst gradient and evaluated for short- and long-term in vitro repopulating cells in the cobblestone area-forming cell (CAFC) assay. The primitive CAFC subset appearing at day 28 in culture was shown to be progressively enriched with decreasing Hoechst fluorescence while the short-term repopulating day 7 CAFC subset frequencies was the highest at an intermediate level of Hoechst staining. We further investigated whether primitive HSCs exist in a very low oxygen tension by administering the reductive 2-nitroimidazole compound pimonidazole in vivo and performed flow cytometric analysis on sorted primitive HSCs residing in high Hoechst dye effluxing side population (SP). In comparison to whole bone marrow or non-SP cells, the SP fraction showed increased intracellular staining with an anti-pimonidazole antibody that recognizes pimonidazole adducts formed only under hypoxic conditions (less than pO2 of 10 mm Hg). Comparison with thymocytes that are already known to be hypoxic in vivo (Hale et al. Am J Physiol Heart Circ Physiol282: H1467–H1477, 2002) showed both low Hoechst dye perfusion and positive anti-pimonidazole antibody staining. These results represent the first direct evidence that the hematopoietic cell hierarchy is spatially organized in relation to blood vessels and that the stem cell niche exists at the lowest end of an oxygen gradient. These findings have important implications in hematopoiesis and stem cell lodgement, and suggest that the location of hematopoietic stem cells in situ may render them more resistant to oxygen-dependent mutagenic and cytotoxic agents.

Description: High dose therapy and autologous stem cell transplantation (ASCT) has been employed as salvage therapy for patients (pts) with relapsed follicular non-Hodgkin’s lymphoma (FL). Recently, the randomized European CUP trial demonstrated that following 3 cycles of CHOP, ASCT significantly improved both disease free and overall survival when compared to continued CHOP in pts with relapsed FL. In an attempt to improve the results of high dose therapy in FL, we undertook 2 sequential studies for pts with FL in first remission. In the first study, 77 pts with previously untreated advanced stage FL (median age 43), received 6–8 cycles of standard dose CHOP (SD-CHOP) + involved field radiotherapy followed by high dose chemoradiotherapy and anti-B cell purged autologous bone marrow transplantation (ABMT). Following SD-CHOP induction, 27 of 77 pts (36%) were in CR and 50 in a minimal disease state (〈 2 cm masses, 〈 20% BM involvement). At BM harvest, 36 pts had histologic evidence of BM involvement. In the second trial, 19 pts with advanced stage disease (median age 44) were treated with 4 cycles of dose intensified CHOP (HD-CHOP) (cyclophosphamide 1.5 g/m2 day 1 and 2) with G-CSF support followed by high dose chemoradiotherapy and anti-B cell purged autologous ABMT. Following HD-CHOP, 13 of 19 pts were in CR. At BM harvest, 7 of the 19 HD-CHOP pts had histologic BM involvement. Following ABMT, there were 2 acute in-hospital deaths in the pts receiving SD-CHOP induction and none in the pts who received HD-CHOP induction. Nine late deaths in remission were observed in the SD-CHOP pts including 6 from MDS/AML, and 2 late deaths in the HD-CHOP pts. Thirty-three pts who received SD-CHOP remain alive without relapse, with a median follow up of 12 years. Ten pts who received HD-CHOP induction remain alive without relapse, with a median follow up of 9.1 years. For pts receiving SD-CHOP induction, the DFS and overall survival at 10 years are 42% (90% CI: 33%–52%) and 64% (90% CI: 55%–73%), respectively. For pts who received HD-CHOP induction, the DFS and overall survival at 10 years are 59% (90% CI: 38%–79%) and 75% (90% CI: 57%–93%), respectively. The impact of BM treatment and DFS was examined. Pts with known bcl-2 translocations for whom post-BM purging samples were available for pcr examination were analyzed. Following ABMT, pts who were reinfused with pcr negative BM had a significantly better DFS than the pts who were reinfused with pcr positive BM. This study suggests that a subset of pts with FL experience long term remission following ABMT in first remission.

Description: Purpose: To describe changes in pulmonary function and subjective dyspnea over time in patients who received bleomycin-based chemotherapy for Hodgkin’s disease (HD) and to identify predictors for decline in pulmonary function and subjective dyspnea after HD therapy Methods: 52 patients with newly-diagnosed classical HD receiving bleomycin-based chemotherapy with or without mediastinal radiation therapy were enrolled. Patients underwent baseline pulmonary function tests (PFTs), and completed the Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-M) pre-treatment. The PFSDQ-M is a 40-item, validated questionnaire measuring the 3 areas of dyspnea, fatigue and activity. The scores range from 0–10, with higher scores representing worse health status. The PFTs and PFSDQ-M were repeated at 1 month, 6 months, 1 year and 2 years post-treatment. Other information collected were number of cycles of bleomycin, radiation dosimetric parameters, and smoking history. This report is based on the 33 patients who had completed treatment and had at least follow-up at 1 month post-treatment. 19 patients received chemotherapy alone and 14 received combined modality therapy. Three-dimensional radiation planning was used and lung dose-volume histograms were generated. Wilcoxon rank sum tests were used to compare the baseline and 1-month objective and subjective lung function results, and to determine whether the addition of radiation therapy to chemotherapy, and among patients who received combined modality therapy, whether the percentage of lung volume receiving 20 Gray (V20), contribute to the changes. A general linear model was used to identify predictors for decline in percentage of predicted carbon monoxide diffusing capacity (%DLCO) at 1 month. Results: At baseline, the median %DLCO was 94% (range: 53–139%). At 1 month post treatment, it was significantly lower at 82% (range: 46–133%) (p=0.0003). Decline in %DLCO at 1 month was not significantly predicted by the addition of mediastinal irradiation (p=0.84), number of cycles of bleomycin (p=0.6), and smoking history (p=0.14), but it was significantly predicted by the baseline %DLCO, with a lower baseline %DLCO associating with less decline in %DLCO (p=0.03). However, the baseline %DLCO also significantly correlated with treatment, with 72% of patients who received chemotherapy alone having a baseline %DLCO =〈 94% (median), compared with 23% of patients treated with combined modality therapy (p=0.011). The median general dyspnea and fatigue scores pre-treatment were 0 (range: 0–6) and 2 (range: 0–7), respectively, and remained the same at 1 month post-treatment. For the 14 patients treated with combined modality therapy, the median V20 was 31.5 % (range: 12–36%). There was no significant effect of V20 on the decline in %DLCO or changes in general dyspnea and general fatigue scores at 1 month. Conclusions: Preliminary results of this study showed significant decline of %DLCO at 1 month post-treatment, but no significant changes in subjective dyspnea and fatigue. None of the treatment-related variables significantly predicted for changes in the pulmonary function at 1 month. The baseline %DLCO was negatively associated with decline in %DLCO, which may be due to response of the mediastinal disease to treatment. However, this association may be confounded by the type of treatment received. Further follow-up is needed to determine the long-term effect of the treatment on lung function.

Description: ASCT improves progression-free and likely overall survival in patients with relapsed follicular lymphoma. Randomized trials of ASCT as upfront therapy have generally also found an improvement in progression-free survival, but this benefit has been counterbalanced by an increase in second malignancies. We report the long-term outcome of two sequential prospective clinical trials of autologous bone marrow transplantation for advanced stage follicular lymphoma patients under 60 in first remission. In the 1st study 83 previously untreated patients received 6–8 cycles of CHOP induction and in the 2nd study 20 patients received 4 cycles of high-dose CHOP induction (cyclophosphamide 1.5 g/m2 d1–2 with g-csf support). The median age of the patients was 42 (range 19–57). 17% had high FLIPI scores, 58% intermediate and 25% low; all patients were under 60 and 21% had missing data required in the FLIPI. 96% had stage III or IV disease. 77 of 83 patients on the 1st study, and 19 of 20 on the 2nd study (N=96 total), achieved a protocol-defined minimal disease state after CHOP induction (〈 2 cm masses,

Description: Previous trials of allogeneic bone marrow transplantation (BMT) in patients with multiple myeloma (MM) have demonstrated high response rates but also high transplantation-related mortality (TRM) and high relapse rates. Exploitation of this strategy remains of interest because donor lymphocyte infusions (DLIs) can induce a potent graft-versus-myeloma (GVM) effect. CD6 T-cell–depleted allogeneic BMT was combined with prophylactic CD4+ DLI administered 6 to 9 months after BMT in an effort to reduce TRM and to induce a GVM response after BMT. Twenty-four patients with matched sibling donors and chemotherapy-sensitive disease underwent BMT. CD6 T-cell depletion of donor bone marrow was the sole method of graft-versus-host disease (GVHD) prophylaxis. GVHD after BMT was minimal, 1 (4%) grade III and 4 (17%) grade II GVHD. Fourteen patients received DLI, 3 in complete response and 11 with persistent disease after BMT. Significant GVM responses were noted after DLI in 10 patients with persistent disease, resulting in 6 complete responses and 4 partial responses. After DLI, 50% of patients developed acute (≥ II) or extensive chronic GVHD. Two-year estimated overall survival and current progression-free survival (PFS) for all 24 patients is 55% and 42%, respectively. The 14 patients receiving DLI had an improved 2-year current PFS (65%) when compared with a historical cohort of MM patients who underwent CD6-depleted BMT survived 6 months with no GVHD and did not receive DLI (41%) (P = .13). Although this study suggests that prophylactic DLI induces significant GVM responses after allogeneic BMT, only 58% of patients were able to receive DLI despite T-cell–depleted BMT. Therefore, less toxic transplantation strategies are needed to allow a higher proportion of patients to receive DLI and the benefit from the GVM effect after transplantation.

Description: The excess risk of second malignancy after Hodgkin disease is an increasing problem. In light of the long-term data, guidelines for follow-up of survivors of Hodgkin disease need to be redefined. In this study we attempt to analyze the long-term risks and temporal trends, identify patient- and treatment-related risk factors, and determine the prognosis of patients who develop a second malignancy after radiation treatment with or without chemotherapy for Hodgkin disease. Among 1319 patients with clinical stage I-IV Hodgkin disease, 181 second malignancies and 18 third malignancies were observed. With a median follow-up of 12 years, the relative risk (RR) and absolute excess risk of second malignancy were 4.6 and 89.3/10 000 person-years. The RR was significantly higher with combined chemotherapy and radiation therapy (6.1) than with radiation therapy alone (4.0, P = .015). The risk increased with increasing radiation field size (P = .03) in patients who received combined modality therapy, and with time after Hodgkin disease. After 15 and 20 years, there was a 2.3% and 4.0% excess risk of second malignancy per person per year. The 5-year survival after development of a second malignancy was 38.1%, with the worst prognosis seen after acute leukemia and lung cancer. The excess risk of second malignancy after Hodgkin disease continues to be increased after 15 to 20 years, and there does not appear to be a plateau. Our analysis suggests that the risk may be reduced with smaller radiation fields, as are used in current trials of abbreviated chemotherapy and limited-field radiation therapy.

Description: We report here on the long-term follow-up on 162 patients with high-risk chronic lymphocytic leukemia (CLL) who have undergone hematopoietic stem cell transplantation (SCT) at a single center from 1989 to 1999. Twenty-five patients with human leukocyte antigen (HLA)-matched sibling donors underwent T-cell-depleted allogeneic SCT, and 137 patients without HLA-matched sibling donors underwent autologous SCT. The 100-day mortality was 4% for both groups, but later morbidity and mortality were negatively affected on outcome. Progression-free survival was significantly longer following autologous than allogeneic SCT, but there was no difference in overall survival and no difference in the cumulative incidence of disease recurrence or deaths without recurrence between the 2 groups. At a median follow-up of 6.5 years there is no evidence of a plateau of progression-free survival. The majority of patients treated with donor lymphocyte infusions after relapse responded, demonstrating a significant graft-versus-leukemia effect in CLL. From these findings we have altered our approach for patients with high-risk CLL and are currently exploring the role of related and unrelated allogeneic SCT following reduced-intensity conditioning regimens.