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H J Sutherland

Publications and source records attributed to H J Sutherland.

At least 37 records · Page 2Linked to original sources

Expression of HOX genes, HOX cofactors, and MLL in phenotypically and functionally defined subpopulations of leukemic and normal human hematopoietic cells.

To explore the possibility that deregulated HOX gene expression might commonly occur during leukemic hematopoiesis, we compared the relative levels of expression of these and related genes in phenotypically and functionally defined subpopulations of AML blasts and normal hematopoietic cells. Initially, a semi-quantitative RT-PCR technique was used to amplify total cDNA from total leukemic blast cell populations from 20 AML patients and light density cells from four normal bone marrows. Expression of HOX genes (A9, A10, B3 and B4), MEIS1 and MLL was easily detected in the majority of AML samples with the exception of two samples from patients with AML subtype M3 (which expressed only MLL). Low levels of HOXA9 and A10 but not B3 or B4 were seen in normal marrow while MLL was easily detected. PBX1a was difficult to detect in any AML sample but was seen in three of four normal marrows. Cells from nine AML patients and five normal bone marrows were FACS-sorted into CD34+CD38-, CD34+CD38+ and CD34-subpopulations, analyzed for their functional properties in long-term culture (LTC) and colony assays, and for gene expression using RT-PCR. 93 +/- 14% of AML LTC-initiating cells, 92 +/- 14% AML colony-forming cells, and >99% of normal LTC-IC and CFC were CD34+. The relative level of expression of the four HOX genes in amplified cDNA from CD34- as compared to CD34+CD38- normal cells was reduced >10-fold. However, in AML samples this down-regulation in HOX expression in CD34- as compared to CD34+CD38- cells was not seen (P < 0.05 for comparison between AML and normal). A similar difference between normal and AML subpopulations was seen when the relative levels of expression of MEIS1, and to a lesser extent MLL, were compared in CD34+ and CD34- cells (P < 0.05). In contrast, while some evidence of down-regulation of PBX1a was found in comparing CD34- to CD34+ normal cells it was difficult to detect expression of this gene in any subpopulation from most AML samples. Thus, the down-regulation of HOX, MEIS1 and to some extent MLL which occurs with normal hematopoietic differentiation is not seen in AML cells with similar functional and phenotypic properties.

ADP-ribosyl Cyclase↗

Most acute myeloid leukemia progenitor cells with long-term proliferative ability in vitro and in vivo have the phenotype CD34(+)/CD71(-)/HLA-DR-.

Acute myeloid leukemia (AML) occurs as the result of malignant transformation in a hematopoietic progenitor cell, which proliferates to form an accumulation of AML blasts. Only a minority of these AML cells are capable of proliferation in vitro, suggesting that AML cells may be organized in a hierarchy, with only the most primitive of these cells capable of maintaining the leukemic clone. To further investigate this hypothesis, we have evaluated a strategy for purifying these primitive cells based on surface antigen expression. As an in vitro endpoint, we have determined the phenotype of AML progenitor cells which are capable of producing AML colony-forming cells (CFU) for up to 8 weeks in suspension culture (SC) and compared the phenotype with that of cells which reproduce AML in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice. AML cells were fluorescence-activated cell sorted (FACS) for coexpression of CD34 and CD71, CD38, and/or HLA-DR and the subfractions were assayed in vitro and in vivo at various cell doses to estimate purification. While the majority of primary AML CFU lacked expression of CD34, most cells capable of producing CFU after 2 to 8 weeks in SC were CD34(+)/CD71(-). HLA-DR expression was heterogeneous on cells producing CFU after 2 to 4 weeks. However, after 6 to 8 weeks in SC, the majority of CFU were derived from CD34(+)/HLA-DR- cells. Similarly, the majority of cells capable of long-term CFU production from SC were CD34(+)/CD38(-). Most cells that were capable of engrafting NOD/SCID mice were also CD34(+)/CD71(-) and CD34(+)/HLA-DR-. Engraftment was not achieved with CD34(+)/CD71(+) or HLA-DR+ subfractions, however, in two patients, both the CD34(+) and CD34(-) subfractions were capable of engrafting the NOD/SCID mice. A three-color sorting strategy combining these antigens allowed approximately a 2-log purification of these NOD/SCID leukemia initiating cells, with engraftment achieved using as few as 400 cells in one experiment. Phenotyping studies suggest even higher purification could be achieved by combining lack of CD38 expression with the CD34(+)/CD71(-) or CD34(+)/HLA DR- phenotype. These results suggest that most AML cells capable of long-term proliferation in vitro and in vivo share the CD34(+)/CD71(-)/HLA-DR- phenotype with normal stem cells. Our data suggests that in this group of patients the leukemic transformation has occurred in a primitive progenitor, as defined by phenotype, with some degree of subsequent differentiation as defined by functional assays.

Acute Disease↗

Cytogenetic abnormalities in primary myelodysplastic syndrome are highly predictive of outcome after allogeneic bone marrow transplantation.

Allogeneic bone marrow transplantation (BMT) is the only curative therapy available for patients with myelodysplastic syndrome (MDS). In an attempt to identify prognostic factors influencing outcome, we collected data retrospectively on 60 consecutive adult patients who had undergone BMT at our center for primary MDS or acute myelogenous leukemia evolving from preexisting primary MDS (sAML). Patients were divided into subgroups according to cytogenetic abnormalities based on a recently described International MDS Workshop categorization system. The 7-year actuarial event-free survival (EFS), relapse rate, and nonrelapse mortality (NRM) for all patients were 29% (95% confidence interval [CI], 16% to 43%), 42% (CI, 24% to 67%), and 50% (CI, 37% to 64%), respectively. The EFS for the good-, intermediate-, and poor-risk cytogenetic subgroups were 51% (CI, 30% to 69%), 40% (CI, 16% to 63%), and 6% (CI, 0% to 24%), respectively (P = .003). The corresponding actuarial relapse rates were 19% (CI, 6% to 49%), 12% (CI, 2% to 61%), and 82% (CI, 48% to 99%), respectively (P = . 002) with no difference in NRM between the subgroups. Univariate analysis showed cytogenetic category, French-American-British (FAB) subtype, and graft-versus-host disease (GVHD) prophylaxis used to be predictive of relapse and EFS. In multivariate analysis, only the cytogenetic category was predictive of EFS, with the relative risk of treatment failure for the good-, intermediate-, and poor-risk cytogenetic subgroups being 1.0, 1.5, and 3.5, respectively (P = . 004). For adults with primary MDS and sAML, even after BMT, poor-risk cytogenetics are predictive of an unfavorable outcome; novel treatment strategies will be required to improve results with allogeneic BMT in this patient population.

Adolescent↗

Self-reported physical and emotional health of women in a low-fat, high-carbohydrate dietary trial (Canada).

OBJECTIVES: While decreased intake of dietary fat may have significant positive effects on women's health by reducing the risk of cancer and other diseases, little research has been carried out to determine the potential adverse effects of dietary fat reduction. This study compares the self-reported physical and emotional health of 402 low fat intervention and control group participants in the Canadian Diet and Breast Cancer Prevention Trial. METHODS: Subjects who had been participating in the dietary intervention trial for at least 2 years completed 3 mailed questionnaires: two designed to assess physical and emotional health (MOS 36-Item Short-Form Health Survey (SF-36) and the Women's Health Questionnaire (WHQ)) and a Health Practices Survey. RESULTS: There were no significant differences between the study groups on total scores or any of the subscales/health domains for the SF-36 or the WHQ. In premenopausal women only, intervention group subjects scored significantly lower on the vasomotor symptoms scale, indicating less symptom experience. Frequency of visits to physicians and alternative health practitioners were not significantly different between the study groups. CONCLUSIONS: The results of this study suggest that participation in a low-fat, high-carbohydrate dietary intervention did not have any detrimental effects on participants' self-reported physical health or emotional well-being.

Adult↗

Admission of bone marrow transplant recipients to the intensive care unit: outcome, survival and prognostic factors.

The role of ICU support in BMT patients is controversial. In an era of constrained resources, the use of prognostic factors predicting outcome may be helpful in identifying patients who are most likely (or unlikely) to benefit from this intervention. We attempted to define the survival of patients admitted to ICU following autologous or allogeneic BMT and to identify those factors important in determining patient outcome. A retrospective study of all adult BMT recipients admitted to intensive care over a 6 year study period was performed to determine overall and prognostic indicators of poor outcome. Pre-treatment, pre-ICU admission and ICU admission data were analyzed to identify factors predicting long-term survival. 116 patients were admitted to ICU on 135 separate occasions with the primary reasons for admission being respiratory failure (66%), sepsis associated with hypotension (10%), and cardiorespiratory failure (8%). No pre-ICU characteristics were predictive of survival. Univariate analysis identified the number of support measures required, the need for ventilation or hemodynamic support, the APACHE II score, the year of ICU admission and the serum bilirubin as significant predictors of post-discharge survival. On multivariate analysis the year of ICU admission, the need for hemodynamic support and the serum bilirubin remained significant. The APACHE II score significantly underestimated survival in the 46% of patients with scores less than 35, and could only be used to predict 100% mortality when it exceeded 45. Twenty-three percent of all BMT patients admitted to the ICU and 17% of ventilated patients survived to hospital discharge. Of the 27 patients surviving to leave hospital, 16 remain alive with a median follow-up of 4.2 years and a mean Karnofsky performance status of 90. Although mortality in BMT recipients admitted to ICU is high our results indicate that intensive care support can be lifesaving and that the outcome in patients requiring ventilation and ICU support may not be as poor as has been previously reported. No single variable was identified which could be used to predict futility but patients requiring both hemodynamic support and mechanical ventilation, and those with an APACHE II score greater than 45 have a very poor prognosis and are unlikely to benefit from lengthy ICU support.

Adolescent↗

High incidence of extramedullary relapse of AML after busulfan/cyclophosphamide conditioning and allogeneic stem cell transplantation.

While allogeneic stem cell transplantation (SCT) is curative for a significant number of patients with AML, relapse of disease within the bone marrow and/or extramedullary (EM) sites following high-dose therapy continues to limit the success of this treatment. Between October 1985 and December 1996, 81 adults underwent allogeneic SCT for de novo AML at our centre. Forty-two patients remain alive and free of leukaemia with a median follow-up of 50 months. The 5-year actuarial event-free survivals (EFS) for all patients and for those undergoing SCT in CR1 or with advanced disease were 46% (95% confidence interval (CI) 34-58%), 63% (CI 46-76%), and 19% (CI 7-36%), respectively. Twenty-two patients relapsed at a median of 8 (range 1.6-54.5) months with the actuarial risk of relapse for all, CR1 and advanced disease patients being 38%, (CI 27-52%), 23% (CI 13-40%) and 68% (CI 46-88%), respectively. Ten patients relapsed at EM sites; six of these (27% of relapses) had an isolated EM relapse at a median of 31 (range 8.5-54) months. Three of the patients with isolated EM relapse survived > or =24 months following relapse and two patients remain disease-free at 29+ and 33+ months. BuCy conditioning followed by allogeneic SCT in AML results in satisfactory EFS although there is a significant risk of late isolated EM relapse.

Adolescent↗

Lymphoproliferative disorders following allogeneic bone marrow transplantation: the Vancouver experience.

Between June 1988 and May 1996, 428 patients underwent allogeneic BMT (288 related donor (RD) and 140 unrelated donor (UD)) at the Vancouver General Hospital. Eight patients (UD six and RD two) developed a post-transplant lymphoproliferative disorder (PTLD). Median age at BMT was 38 years (range 22-51). Five of the six UD allografts were T cell depleted. Cyclosporine+/-methotrexate was used for GVHD prophylaxis. All eight patients developed GVHD; in six this was refractory to treatment with corticosteroids. Rabbit antithymocyte globulin (ATG) or an anti-CD5-ricin A chain immunotoxin (Xomazyme) was used as second-line therapy for GVHD. Presentation with PTLD occurred at median day 90.5 (range 34-282) post BMT. Five of the eight patients had a rapidly progressive course characterized by fever, lymphadenopathy, lung and liver involvement and died within 3-8 days. PTLD was an incidental finding at post mortem examination in two patients. The remaining patient had localized disease and recovered. Pathological analysis revealed two morphological patterns; diffuse large B cell lymphoma (DLBC lymphoma, five patients) and polymorphous B cell hyperplasia (PBCH, three patients). EBV expression was positive in all eight cases and monoclonality was demonstrated in seven cases. In multivariate analysis, T cell depletion of the allograft (P=0.0001, relative risk (RR)=30.5), anti-T cell therapy for GVHD (P=0.006, RR=12.7) and acute GVHD grades 3-4 (P=0.04, RR=7.7) were the significant factors for development of PTLD. In conclusion, we have identified two forms of PTLD after BMT: one is characterized by disseminated disease with a rapidly progressive and often fulminant course and the other by localized, relatively indolent disease. Morphology, EBV positivity and clonality do not appear to correlate with the clinical course. The major risk factors for development of PTLD after BMT are ex vivo T cell depletion of the allograft and in vivo anti-T cell therapy for GVHD.

Adolescent↗

Bone marrow transplantation for adults with acute leukaemia and 11q23 chromosomal abnormalities.

Adults with acute leukaemia and abnormalities of chromosome 11q23 have a poor prognosis when treated with conventional chemotherapy. To determine whether more intensive therapy can improve outcome for patients with this karyotypic finding, a retrospective analysis of all patients with acute leukaemia and 11q23 abnormalities treated at our centre was performed. 12 patients were treated with conventional chemotherapy alone (CC); 20 patients received high-dose chemo/radiotherapy (HDCT) with autologous (seven patients) or allogeneic (13 patients) bone marrow transplantation (BMT). The treatment-related mortality was 25% [95% Confidence Interval (CI) 7-69%] for the CC group and 46% (CI 25-73%) for the BMT group (P = 0.69). Cumulative risk of leukaemia progression was 89% (CI 61-100%) in the CC patients and 38% (CI 12-69%) in the BMT patients (P = 0.001). The 2-year event-free survival for patients treated with CC was 8% (CI 0-31%) and for patients receiving HDCT and BMT was 34% (CI 14-54%) (P = 0.03). These results confirm that conventional chemotherapy is rarely curative for adults with acute leukaemia and 11q23 abnormalities but that HDCT with BMT can result in long-term survival in a significant proportion of patients.

Acute Disease↗

Lack of expression of Thy-1 (CD90) on acute myeloid leukemia cells with long-term proliferative ability in vitro and in vivo.

Acute myeloid leukaemia (AML) is thought to be maintained by a small population of leukemic progenitor cells. To define the phenotype of such cells with long-term proliferative capacity in vitro and in vivo, we have used the production of leukemic clonogenic cells (CFU) after 2 to 8 weeks in suspension culture as a measure of these cells in vitro and compared their phenotype with that of cells capable of engrafting nonobese diabetic severe combined immune deficient (NOD/SCID) mice. Leukemic blast peripheral blood cells were evaluated for expression of CD34 and Thy-1 (CD90) antigens. The majority of AML blast cells at diagnosis lacked expression of Thy-1. Most primary CFU-blast and the CFU detected at up to 8 weeks from suspension cultures were CD34+/Thy-1-. AML cells that were capable of engrafting NOD/SCID mice were also found to have the CD34+/Thy-1- phenotype. However, significant engraftment was achieved using both CD34+/Thy-1- and CD34- subfractions from one AML M5 patient. These results suggest that while heterogeneity exists between individual patients, the leukemic progenitor cells that are capable of maintaining the disease in vitro and in vivo differ from normal hematopoietic progenitor cells in their lack of expression of Thy-1.

Animals↗

Quality of life following bone marrow transplantation: a comparison of patient reports with population norms.

All surviving patients who had received an allogeneic bone marrow transplant at the Princess Margaret Hospital were asked to participate in a health-related quality of life (HQL) study using the Medical Outcomes Survey-Short Form 36 (MOS SF-36), the Satisfaction with Life Domains Scale-Bone Marrow Transplantation (SLDS-BMT) and a current symptoms checklist. The main objective was to compare the health status of BMT survivors with age-adjusted population norms. Of the 251 patients contacted, 93% returned questionnaires. The median follow-up after BMT was 40 months, ranging from 1-253 months. On average, survivors had some diminished HQL relative to the health status of the population in general. Time since transplant had a significant influence on HQL; those less than 3 years from transplant experienced considerable impairment while those who had survived beyond this point were indistinguishable from the normal population in most domains and significantly better in certain psychosocial aspects of health. Many patients still reported symptoms months after BMT; some were mildly affected while others experienced more troublesome symptoms. However, 81% of patients were satisfied with the HQL outcome that they had achieved and 94% would recommend a transplant for someone in similar circumstances.

Adult↗

Induction failure in de novo acute myelogenous leukemia is associated with expression of high levels of CD34 antigen by the leukemic blasts.

The prognostic significance of CD34 antigen expression in acute myelogenous leukemia (AML) is controversial. Most studies to date have reported on CD34 positivity and not the level of antigen present. In this study of 62 patients with de novo AML, 48 (77%) patients were CD34+ in varying levels (0-85 mean channels of fluorescence (MCF)). Forty seven of 62 were treated with combination chemotherapy and 39 (83%) of them achieved complete remission (CR). Patients with CD34- blasts were more likely to achieve CR; however, this trend was not statistically significant (p = .11). On the other hand, patients with higher levels of CD34 antigen on the blasts were less likely to attain CR (p < 0.001, multivariate analysis). The patients who achieved CR expressed lower levels of CD34 (0-57; median 9 MCF) as compared to those who did not achieve CR (15-85; median 30 MCF). Of the other antigens tested, partial or complete absence of CD33 (CD33 absent in > or =25% blasts) correlated with failure to achieve CR (p = 0.0029). These results are in keeping with the hypothesis that more primitive AML blasts with high levels of CD34 are chemoresistant.

Adult↗

Characterization of a hierarchy in human acute myeloid leukemia progenitor cells.

Despite the usual uniform and primitive appearance of cells derived from the leukemic clone in most patients with acute myeloid leukemia (AML), there is considerable heterogeneity among leukemic blasts, particularly with respect to their capacity to proliferate and/or self renew. We have assessed whether these differences in proliferative potential are correlated with the phenotypic changes that characterize normal hematopoiesis, which might suggest an analogous hierarchy of AML progenitors. We have used the ability of primitive AML cells to persist or produce blast colony forming cells (CFU-blast) detected after 2 to 8 weeks in the presence of growth factors in suspension cultures (SC) termed SC-initiating cells (IC), or with stroma in long-term cultures (LTC-IC) as a quantitative assay for a cell that may have primitive characteristics. This SC assay is linear, cell concentration independent, and the frequency of SC-IC by limiting dilution analysis is lower than primary CFU-blast. The average output of CFU-blast after 2 to 8 weeks by individual SC-IC varied between 2 and more than 100 in individual patients. Leukemic blasts were sorted based on their expression of antigens previously found useful to characterize normal progenitor differentiation, and analyzed for the percentage of CFU-blast SC-IC, and leukemic LTC-IC within each fraction. All of these progenitor types were heterogeneous in their expression of CD45RA and CD33, but expressed uniformly low levels of CD15 and differed from normal primitive progenitors in their high expression of HLA-DR. CFU-blast had a significantly higher expression of CD71 and CD38 as compared with SC-IC or leukemic LTC-IC. In patients with CD34+ blasts, the majority of their SC-IC at 4 weeks were CD34+/CD38-; however, patients with CD34- blasts had at least some CD34- progenitors. These results show that while heterogeneity exists between patients, it is possible to physically separate subpopulations of AML cells with different proliferative potentials. It also provides some support for the concept that quantitation of leukemic cells capable of producing CFU-blast for 4 weeks or more in vitro measures a less frequent leukemic progenitor with higher proliferative potential that may be the only relevant cell for maintaining the leukemic clone in vivo.

Acute Disease↗

A randomized trial of the total design method for the postal follow-up of women in a cancer prevention trial.

Mail surveys have been used to follow-up early participants in a Canadian breast cancer prevention trial. To minimize non-response bias, we undertook a randomized study of two postal strategies, of which one was our usual procedure and the other was a systematic application, known as the total design method (TDM) and described by Dillman. The response rates to the two methods were 62 and 88% respectively. The TDM is a practical, cost-efficient approach to reducing non-response bias in postal surveys and as such has an important role in epidemiological research which involves healthy participants.

Adult↗

High-dose cyclophosphamide, carmustine (BCNU), and etoposide (VP16-213) with or without cisplatin (CBV +/- P) and autologous transplantation for patients with Hodgkin's disease who fail to enter a complete remission after combination chemotherapy.

Patients with Hodgkin's disease (HD) who fail to enter a complete remission after an initial course of combination chemotherapy are usually considered to have an induction failure (IF); this subset of patients has an extremely poor outcome with further conventional therapy. Since 1985, we have entered 30 IF patients into protocols using conditioning with high-dose cyclophosphamide, carmustine (BCNU), and etoposide (VP16-213) with or without cisplatin (CBV +/- P) followed by autologous stem cell transplantation (ASCT) with bone marrow (19 patients), peripheral blood stem cells (PBSCs; 8 patients), or both (3 patients). All except 2 patients had previously received chemotherapy regimens for HD that contained at least 7 drugs, and 9 had received prior radiotherapy (RT). After documentation of IF, the majority of patients received some cytoreductive therapy as specified by protocol (local RT in 9, two cycles of conventional chemotherapy in 2, both modalities in 2, or high-dose cyclophosphamide to enhance PBSC collection in 11) before CBV +/- P. Five treatment-related deaths occurred, all before day 150 posttransplant. Eleven patients have had progressive HD at a median of 6 months (range, 0.1 to 45 months) after ASCT. The actuarial progression-free survival (PFS) at a median follow-up of 3.6 years (range, 0.2 to 8.2 years) is 42% (95% confidence intervals, 21% to 61%). The statistical analysis identified only prior clinical bleomycin lung toxicity as an adverse risk factor for PFS, mainly because of the increased nonrelapse mortality seen in these patients. CBV +/- P and ASCT can produce durable remission in a substantial proportion of IF HD patients who otherwise have a poor survival, and we believed ASCT approaches represent the best therapy currently available for these patients. Additional measures are needed to reduce the primary problem of disease progression despite high-dose chemotherapy and stem cell transplantation.

Actuarial Analysis↗

Platelet refractoriness and alloimmunization in pediatric oncology and bone marrow transplant patients.

BACKGROUND: The purposes of this study were to determine the overall incidence of platelet refractoriness and alloimmunization among multiply transfused children on a medical oncology and bone marrow transplant service and to evaluate the effect of routine white cell reduction in blood components on that incidence. STUDY DESIGN AND METHODS: The platelet transfusion records of 128 consecutive children admitted to the hospital and requiring blood component support for the treatment of disease were evaluated retrospectively. Mean corrected count increments (CCIs) for each patient were calculated for all random-donor platelet transfusions given within 7 days of the routine weekly testings of the patient's serum for lymphocytotoxic antibodies (LCTAbs). Mean CCIs for HLA-matched platelet transfusions were calculated separately for the patients receiving them. RESULTS: Thirty-one patients (24%) had or developed persistently positive LCTAbs (patient's serum reacted with > or = 3/10 panel lymphocytes); 22 (71%) of these patients had a mean CCI < 7.5 to random-donor platelet transfusions. In contrast, of the 97 patients with negative or transiently positive LCTAbs, only 25 (26%) had a mean CCI < 7.5. The overall incidence of platelet refractoriness (CCI < 7.5) was 37 percent. Patients with acute myelogenous leukemia had a significantly (p < 0.01) reduced incidence (17%) of low CCIs, with or without positive LCTAbs, as compared to patients with other malignant or nonmalignant disorders (41%). No difference in the incidence of LCTAbs or low CCIs was seen in patients undergoing allogeneic or autologous bone marrow transplant or receiving drug therapy only. Among the 24 patients who received HLA-matched platelets, only those with positive LCTAbs showed a significant improvement in CCIs over that achieved with random-donor platelet transfusions. Routine white cell reduction in red cell and platelet components with third-generation white cell filters was performed prior to transfusion in 73 of the patients. There was no significant difference between the incidence of LCTAbs and/or low CCIs in this group and that in the 55 children receiving unfiltered transfusions. CONCLUSION: Alloimmunization and platelet refractoriness occur in pediatric oncology and bone marrow transplant patients, but the incidence--particularly in children with acute myelogenous leukemia--appears to be low. The detection of LCTAbs predicts a poor response to random-donor platelet transfusion, but most such patients show improved CCIs with HLA-matched platelets. Routine use of white cell-reduction filters has thus far failed to eliminate alloimmunization in children requiring prolonged blood component support.

Adolescent↗

Quantitation, mobilization, and clinical use of long-term culture-initiating cells in blood cell autografts.

Mobilized peripheral blood is increasingly used as a source of cells to provide hematopoietic reconstitution in marrow ablated patients. There is controversy as to how the engraftment potential of these preparations should be evaluated. The long-term culture-initiating cell is a very primitive hematopoietic with unique phenotypic feature. The potential role and significance of these cells in peripheral blood cell autografts is discussed.

Animals↗

Acute monocytic leukemia: a single institution experience.

Using strict FAB criteria, 39 cases of monocytic leukemia were identified in 463 consecutive cases of AML. Patients had a median age of 49 with no sex predominance. Extramedullary disease and hyperleukocytosis were common (54% and 36% of patients respectively). Cytogenetic analysis was successful in 38 of 39 patients; 71% had a cytogenetic abnormality and 42% of these involved chromosome 11; 14 of 16 chromosome 11 abnormalities involved the region of 11q23. Non-chromosome 11 abnormalities tended to occur in older patients and to be associated with a lower platelet count; patients with the translocation 9;11 tended to have a lower white count and a higher incidence of therapy-related leukemia. 35 patients were treated with induction therapy including intensive chemotherapy (n = 33) and allogeneic BMT at presentation (n = 2). Patients who entered remission underwent consolidation chemotherapy, autologous BMT, or allogeneic BMT depending on policies at the time of diagnosis. Of 6 patients who underwent further intensive chemotherapy there is 1 long-term disease-free survivor. 3 of 8 patients undergoing autologous BMT and 2 of 3 patients undergoing allogeneic BMT are long-term disease-free survivors. We conclude that this specific subtype of AML, relatively rare when strict criteria are applied, is associated with unique biologic and clinical features and that the high relapse rate associated with conventional therapy makes new treatment approaches involving stem cell transplantation or immunomodulation necessary.

Adult↗