Effects on tumor development and metastatic dissemination by the NKG2D lymphocyte receptor expressed on cancer cells

The stimulatory NKG2D lymphocyte receptor together with its tumor-associated ligands enable the immune system to recognize and destroy cancer cells. However, with dynamic changes unfolding, cancers exploit NKG2D and its ligands for immune evasion and suppression. Recent findings have added yet another functional dimension wherein cancer cells themselves coopt NKG2D for their own benefit to complement the presence of its ligands for self stimulation of parameters of tumorigenesis. Those findings are here extended to in vivo tumorigenicity testing by employing orthotopic xenotransplant breast cancer models in mice. Using human cancer lines with ectopic NKG2D expression and RNAi-mediated protein depletion among other controls, we show that NKG2D self-stimulation has tumor promoting capacity. NKG2D signals had no notable effects on cancer cell proliferation and survival but acted at the level of angiogenesis, thus promoting tumor growth, tumor cell intravasation and dissemination. NKG2D-mediated effects on tumor initiation may represent another factor in the observed overall enhancement of tumor development. Altogether, these results may impact immunotherapy approaches, which currently do not account for such NKG2D effects in cancer patients and thus could be misdirected as underlying assumptions are incomplete.

Frequency of allogeneic hematopoietic cell transplantation among patients with high- or intermediate-risk acute myeloid leukemia in first complete remission

PURPOSE

To determine the frequency of allogeneic hematopoietic cell transplantation (HCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1).

PATIENTS AND METHODS

Between January 1, 2008, and March 1, 2011, 212 newly diagnosed patients with AML received treatment at our center. Ninety-five patients age less than 75 years with intermediate- or high-risk AML achieved a complete remission, and 21 patients achieved a morphologic remission with incomplete blood count recovery.

RESULTS

Seventy-eight (67%; 95% CI, 58% to 76%) of 116 patients received HCT at a median of 2.8 months (range, 0.5 to 19 months) from their CR1 date. The median age was 57 years in both the HCT patient group (range, 18 to 75 years) and the non-HCT patient group (range, 24 to 70 years; P = .514). Between the HCT patients and the non-HCT patients, the mean Eastern Cooperative Oncology Group performance status was 1.1 compared with 1.5, respectively (P = .005), and the average HCT comorbidity score within 60 days of CR1 was 1.7 and 2.1, respectively (P = .68). Twenty-nine (76%) of 38 non-HCT patients were HLA typed, and matched donors were found for 13 of these 29 patients (34% of all non-HCT patients). The most common causes for patients not receiving transplantation in CR1 were early relapse (within 6 months) in 12 patients (32%), poor performance status in eight patients (21%), and physician decision in five patients (13%).

CONCLUSION

HCT can be performed in CR1 in the majority of patients with AML for whom it is currently recommended. The main barriers to HCT were early relapse and poor performance status, highlighting the need for improved therapies for patients with AML of all ages.

Characteristics of chronic GVHD after cord blood transplantation

Most reports of chronic GVHD after cord blood transplantation (CBT) have utilized traditional diagnostic criteria. We used traditional criteria and National Institutes of Health (NIH) criteria prospectively to evaluate chronic GVHD in a cohort of 87 adult and pediatric recipients of single or double unrelated CBT for treatment of hematologic malignancies. Fifty-four patients developed traditionally defined chronic GVHD, for an estimated 2-year probability of 64%. Among 54 patients, 25 (46%) met the NIH criteria for persistent, recurrent or late acute GVHD at onset. Twenty-four (44%) had overlap chronic GVHD, including one who presented initially with late acute GVHD, and only seven (13%) had classic chronic GVHD, including one who also presented initially with late acute GVHD. Among patients who successfully discontinued all systemic immunosuppression (SI), the median time to discontinuation of corticosteroid treatment was 315 days (range 28-977), and the median time to discontinuation of all SI was 353 days (range 67-977). Chronic GVHD diagnosed by traditional criteria after CBT had a predominance of acute GVHD clinical features.

A phase I study of pulse high-dose vorinostat (V) plus rituximab (R), ifosphamide, carboplatin, and etoposide (ICE) in patients with relapsed lymphoma

Given the poor outcomes of relapsed aggressive lymphomas and preclinical data suggesting that ≥2·5 μmol/l concentrations of vorinostat synergize with both etoposide and platinums, we hypothesized that pulse high-dose vorinostat could safely augment the anti-tumour activity of (R)ICE [(rituximab), ifosphamide, carboplatin, etoposide] chemotherapy. We conducted a phase I dose escalation study using a schedule with oral vorinostat ranging from 400 mg/d to 700 mg bid for 5 d in combination with the standard (R)ICE regimen (days 3, 4 and 5). Twenty-nine patients [median age 56 years, median 2 prior therapies, 14 chemoresistant (of 27 evaluable), 2 prior transplants] were enrolled and treated. The maximally tolerated vorinostat dose was defined as 500 mg twice daily × 5 d. Common dose limiting toxicities included infection (n = 2), hypokalaemia (n = 2), and transaminitis (n = 2). Grade 3 related gastrointestinal toxicity was seen in 9 patients. The median vorinostat concentration on day 3 was 4·5 μmol/l (range 4·2-6·0 μmol/l) and in vitro data confirmed the augmented antitumour and histone acetylation activity at these levels. Responses were observed in 19 of 27 evaluable patients (70%) including 8 complete response/unconfirmed complete response. High-dose vorinostat can be delivered safely with (R)ICE, achieves potentially synergistic drug levels, and warrants further study, although adequate gastrointestinal prophylaxis is warranted.

HLA-C-dependent prevention of leukemia relapse by donor activating KIR2DS1

BACKGROUND

Of the cancers treated with allogeneic hematopoietic stem-cell transplantation (HSCT), acute myeloid leukemia (AML) is most sensitive to natural killer (NK)-cell reactivity. The activating killer-cell immunoglobulin-like receptor (KIR) 2DS1 has ligand specificity for HLA-C2 antigens and activates NK cells in an HLA-dependent manner. Donor-derived NK reactivity controlled by KIR2DS1 and HLA could have beneficial effects in patients with AML who undergo allogeneic HSCT.

METHODS

We assessed clinical data, HLA genotyping results, and donor cell lines or genomic DNA for 1277 patients with AML who had received hematopoietic stem-cell transplants from unrelated donors matched for HLA-A, B, C, DR, and DQ or with a single mismatch. We performed donor KIR genotyping and evaluated the clinical effect of donor KIR genotype and donor and recipient HLA genotypes.

RESULTS

Patients with AML who received allografts from donors who were positive for KIR2DS1 had a lower rate of relapse than those with allografts from donors who were negative for KIR2DS1 (26.5% vs. 32.5%; hazard ratio, 0.76; 95% confidence interval [CI], 0.61 to 0.96; P=0.02). Of allografts from donors with KIR2DS1, those from donors who were homozygous or heterozygous for HLA-C1 antigens could mediate this antileukemic effect, whereas those from donors who were homozygous for HLA-C2 did not provide any advantage (24.9% with homozygosity or heterozygosity for HLA-C1 vs. 37.3% with homozygosity for HLA-C2; hazard ratio, 0.46; 95% CI, 0.28 to 0.75; P=0.002). Recipients of KIR2DS1-positive allografts mismatched for a single HLA-C locus had a lower relapse rate than recipients of KIR2DS1-negative allografts with a mismatch at the same locus (17.1% vs. 35.6%; hazard ratio, 0.40; 95% CI, 0.20 to 0.78; P=0.007). KIR3DS1, in positive genetic linkage disequilibrium with KIR2DS1, had no effect on leukemia relapse but was associated with decreased mortality (60.1%, vs. 66.9% without KIR3DS1; hazard ratio, 0.83; 95% CI, 0.71 to 0.96; P=0.01).

CONCLUSIONS

Activating KIR genes from donors were associated with distinct outcomes of allogeneic HSCT for AML. Donor KIR2DS1 appeared to provide protection against relapse in an HLA-C-dependent manner, and donor KIR3DS1 was associated with reduced mortality. (Funded by the National Institutes of Health and others.).

Early CD3 peripheral blood chimerism predicts the long-term engrafting unit following myeloablative double-cord blood transplantation

After double-cord blood transplantation, long-term hematopoietic dominance of a single-cord blood donor graft is established in the majority of patients; however, the mechanism behind this observation remains largely unknown. Beginning at day 7 posttransplantation, we prospectively measured weekly lineage-specific peripheral blood donor chimerisms in patients undergoing myeloablative double-cord blood transplantation to evaluate whether the degree of early donor contribution to specific lineage(s) would predict the long-term engrafting unit. Our results demonstrate that the donor unit with higher CD3 chimerism at day 7 became the dominant engrafting unit in 26 of 31 evaluable patients (P = .0002) and in 34 of 34 evaluable patients at day 14 (P < .0001). Similarly, higher donor unit CD33 chimerism was associated with dominant engraftment in 8 of 8 (day 7) and in 31 of 32 (day 14) evaluable patients. No statistically significant correlation between the dominant unit and order of infusion, infused total nucleated cells, CD34, or CD3 cell doses, unit viability, or HLA disparity was observed. The correlation of higher early posttransplantation donor CD3 peripheral blood chimerism with the dominant unit suggests a rapid immune-mediated response as a primary mechanism of action for long-term single-donor dominance. This finding may have clinical implications for early selection of the winning unit after double-cord blood transplantation and for novel cord blood manipulation strategies.

Predicting relapse prior to transplantation in chronic myeloid leukemia by integrating expert knowledge and expression data

MOTIVATION

Selecting a small number of signature genes for accurate classification of samples is essential for the development of diagnostic tests. However, many genes are highly correlated in gene expression data, and hence, many possible sets of genes are potential classifiers. Because treatment outcomes are poor in advanced chronic myeloid leukemia (CML), we hypothesized that expression of classifiers of advanced phase CML when detected in early CML [chronic phase (CP) CML], correlates with subsequent poorer therapeutic outcome.

RESULTS

We developed a method that integrates gene expression data with expert knowledge and predicted functional relationships using iterative Bayesian model averaging. Applying our integrated method to CML, we identified small sets of signature genes that are highly predictive of disease phases and that are more robust and stable than using expression data alone. The accuracy of our algorithm was evaluated using cross-validation on the gene expression data. We then tested the hypothesis that gene sets associated with advanced phase CML would predict relapse after allogeneic transplantation in 176 independent CP CML cases. Our gene signatures of advanced phase CML are predictive of relapse even after adjustment for known risk factors associated with transplant outcomes.

Pretransplantation therapy with azacitidine vs induction chemotherapy and posttransplantation outcome in patients with MDS

Although allogeneic hematopoietic cell transplantation (HCT) has proven curative potential for myelodysplastic syndrome, relapse after HCT remains a problem. Pretransplantation cytoreduction with induction chemotherapy (IC) has been used to reduce relapse rates but is associated with significant toxicity and mortality. Hypomethylating agents may achieve cytoreduction with limited toxicity; however, data on the effect of pre-HCT hypomethylation on post-HCT outcomes are limited. We retrospectively reviewed results in 68 patients who underwent allogeneic HCT for myelodysplastic syndrome or acute myeloid leukemia transformed from MDS. Thirty-five patients had received cytoreduction with azacitidine before HCT with either a high-dose (40%) or a reduced-intensity (60%) conditioning regimen, and 33 had undergone IC before HCT with high-dose conditioning. The estimated 1-year overall survival (OS) was 57% in the azacitidine group and 36% in the IC group. The risk of post-HCT mortality (hazard ratio, 0.68; 95% confidence interval, 0.35-1.30), nonrelapse mortality (hazard ratio, 0.99; 95% confidence interval, 0.41-2.34), and relapse (hazard ratio, 0.34; 95% confidence interval, 0.41-2.34) were lower in the azacitidine group compared to the IC group, but only the hazard for relapse was significantly lower. After adjustment for cytogenetic risk, International Prognostic Scoring System, and donor, the rates of post-HCT relapse for the 2 cohorts were similar. Although the current study was retrospective and nonrandomized and needs to be interpreted in this context, the results add to the growing evidence that pre-HCT therapy with azacitidine is associated with less toxicity than IC and may allow for similar post-HCT outcomes.

Autologous hematopoietic cell transplantation following high-dose immunosuppressive therapy for advanced multiple sclerosis: long-term results

The purpose of the study was to determine the long-term safety and effectiveness of high-dose immunosuppressive therapy (HDIT) followed by autologous hematopoietic cell transplantation (AHCT) in advanced multiple sclerosis (MS). Total body irradiation, cyclophosphamide, and antithymocyte globulin were followed by transplantation of autologous, CD34-selected peripheral blood stem cells (PBSC). Neurological examinations, brain MRIs and cerebrospinal fluid (CSF) for oligoclonal bands (OCB) were serially evaluated. Patients (n=26, mean EDSS=7.0, 17 secondary progressive, 8 primary progressive, 1 relapsing/remitting) were followed for a median of 48 months after HDIT followed by AHCT. The 72-month probability of worsening ≥ 1.0 EDSS point was 0.52 (95% CI, 0.30 to 0.75). Five patients had an EDSS at baseline of ≤ 6.0; four of these had not failed treatment at last study visit. OCB in CSF persisted with minor changes in the banding pattern. Four new or enhancing lesions were seen on MRI, all within 13 months of treatment. In this population with high baseline EDSS, a significant proportion of patients with advanced MS remained stable as long as 7 years after transplant. Non-inflammatory events may have contributed to neurological worsening after treatment. HDIT/AHCT may be more effective in patients with less advanced relapsing/remitting MS.

Who will manage American patients with diabetes? Residents' career preferences and perceptions of diabetes care

OBJECTIVE

To identify the factors that encourage or discourage internal medicine and pediatric residents regarding specializing in endocrinology with a focus on diabetes.

METHODS

We conducted an electronic survey of internal medicine and pediatric residents using a $10 participation incentive. A total of 653 residents responded to the survey (estimated response rate of 9.2%)-626 from residency programs that were contacted for our survey and 27 from referrals.

RESULTS

Among internal medicine and pediatric residents surveyed, 39 respondents (6.0%) planned to specialize in endocrinology, and 27 of these (4.1% of total respondents) planned to focus on diabetes. "Intellectual satisfaction," "emotional satisfaction," and "work-life balance" were identified by respondents as the most important factors in their choice of a specialty, with ratings of 5.5, 5.4, and 5.3 on a 6-point Likert scale. Among these factors identified as most important to a medical career, endocrinology with a focus on diabetes scored poorly with regard to intellectual and emotional satisfaction but received high ranking with regard to lifestyle. With regard to other factors, endocrinology was rated negatively on "compensation," "number of procedures," and "patient adherence to prescribed treatment." Exposure to diabetes during training had no major influence on the decision to enter endocrinology.

CONCLUSION

Endocrinology with a focus on diabetes care is not an attractive specialty for most internal medicine and pediatric residents. Therefore, new strategies to attract residents to the field of diabetes care are needed.

Histology and time to progression predict survival for lymphoma recurring after reduced-intensity conditioning and allogeneic hematopoietic cell transplantation

Reduced-intensity conditioning (RIC) before allogeneic hematopoietic cell transplantation (HCT) is increasingly used as a potentially curative option for patients with advanced lymphoma; however, relapse remains a major challenge. Unfortunately, little data are available on outcomes, predictors of survival, and results of specific management strategies in these patients. In the present study, a total of 101 consecutive relapses occurred and were evaluated in 280 patients with lymphoma who underwent RIC HCT. Diseases included aggressive non-Hodgkin lymphoma (NHL) (n = 42), indolent NHL (n = 33), and Hodgkin lymphoma (HL) (n = 26). Median time to relapse was 90 days (range, 3-1275 days), and graft-versus-host disease at relapse was present in 56 patients (55%). Interventions after relapse included no therapy (n = 14), withdrawal of immunosuppression alone (n = 11), chemoradiotherapy (n = 60), and donor lymphocyte infusion/second HCT (n = 16). Overall survival (OS) was 33% (95% confidence interval [CI], 23%-44%) at 3 years after relapse and 23% (95% CI, 13%-34%) at 5 years after relapse. Both aggressive NHL (vs indolent disease; hazard ratio, 2.29; P = .008) and relapse within 1 month post-HCT (vs >6 months; hazard ratio, 3.17; P = .004) were associated with increased mortality. Estimated 3-year OS was 16% (95% CI, 5%-32%) after relapse for aggressive NHL, 40% (95% CI, 19%-61%) after relapse for indolent NHL, and 47% (95% CI, 29%-64%) after relapse for HL. The 1-year survival was 24% for patients relapsing within 1 month post-HCT, compared with 52% for those relapsing at 1-3 months, 74% for those relapsing at 3-6 months, and 77% for those relapsing at more than 6 months. We conclude that despite relapse of lymphoma after RIC HCT, some patients may experience prolonged survival, with better postrelapse outcomes occurring in patients with indolent NHL, HL, or late relapse.

Expression, signaling proficiency, and stimulatory function of the NKG2D lymphocyte receptor in human cancer cells

The stimulatory natural killer group 2 member D (NKG2D) lymphocyte receptor and its tumor-associated ligands are important mediators in the immune surveillance of cancer. With advanced human tumors, however, persistent NKG2D ligand expression may favor tumor progression. We have found that cancer cells themselves express NKG2D in complex with the DNAX-activating protein 10 (DAP10) signaling adaptor. Triggering of NKG2D on ex vivo cancer cells or on tumor lines which express only few receptor complexes activates the oncogenic PI3K-protein kinase B (PKB/AKT)-mammalian target of rapamycin (mTOR) signaling axis and downstream effectors, the ribosomal protein S6 kinase 1 (S6K1) and the translation initiation factor 4E-binding protein 1 (4E-BP1). In addition, as in lymphocytes, NKG2D ligand engagement stimulates phosphorylation of JNK and ERK in MAP kinase cascades. Consistent with these signaling activities, above-threshold expression of NKG2D-DAP10 in a ligand-bearing tumor line increases its bioenergetic metabolism and proliferation, thus suggesting functional similarity between this immunoreceptor and tumor growth factor receptors. This relationship is supported by significant correlations between percentages of cancer cells that are positive for surface NKG2D and criteria of tumor progression. Hence, in a conceptual twist, these results suggest that tumor co-option of NKG2D immunoreceptor expression may complement the presence of its ligands for stimulation of tumor growth.

Impact of pretransplantation minimal residual disease, as detected by multiparametric flow cytometry, on outcome of myeloablative hematopoietic cell transplantation for acute myeloid leukemia

PURPOSE

Allogeneic hematopoietic cell transplantation (HCT) benefits many patients with acute myeloid leukemia (AML) in first remission. Hitherto, little attention has been given to the prognostic impact of pretransplantation minimal residual disease (MRD).

PATIENTS AND METHODS

We retrospectively studied 99 consecutive patients receiving myeloablative HCT for AML in first morphologic remission. Ten-color multiparametric flow cytometry (MFC) was performed on bone marrow aspirates before HCT. MRD was identified as a cell population showing deviation from normal antigen expression patterns compared with normal or regenerating marrow. Any level of residual disease was considered MRD positive.

RESULTS

Before HCT, 88 patients met morphologic criteria for complete remission (CR), whereas 11 had CR with incomplete blood count recovery (CRi). Twenty-four had MRD before HCT as determined by MFC. Two-year estimates of overall survival were 30.2% (range, 13.1% to 49.3%) and 76.6% (range, 64.4% to 85.1%) for MRD-positive and MRD-negative patients; 2-year estimates of relapse were 64.9% (range, 42.0% to 80.6%) and 17.6% (range, 9.5% to 27.9%). After adjustment for all or a subset of cytogenetic risk, secondary disease, incomplete blood count recovery, and abnormal karyotype pre-HCT, MRD-positive HCT was associated with increased overall mortality (hazard ratio [HR], 4.05; 95% CI, 1.90 to 8.62; P < .001) and relapse (HR, 8.49; 95% CI, 3.67 to 19.65; P < .001) relative to MRD-negative HCT.

CONCLUSION

These data suggest that pre-HCT MRD is associated with increased risk of relapse and death after myeloablative HCT for AML in first morphologic CR, even after controlling for other risk factors.

Allogeneic hematopoietic cell transplantation with full-intensity conditioning for adult acute lymphoblastic leukemia: results from a single center, 1998-2006

A retrospective analysis identified 161 consecutive adults with acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation (HCT) with full-intensity (myeloablative) conditioning between 1998 and 2006. Median patient age was 36.1 years. Seventy-six patients were in first complete remission (CR1), and 85 were in second or greater CR or in relapse. Fifty-nine patients had Philadelphia chromosome-positive acute lymphoblastic leukemia. A total of 159 patients received chemotherapy plus total body irradiation for conditioning. Graft-versus-host disease prophylaxis included a calcineurin inhibitor plus methotrexate or mycophenolate mofetil. Sixty of the donors were related, and 101 were unrelated. A total of 110 patients received granulocyte-colony stimulating factor-stimulated peripheral blood, 47 received bone marrow, and 4 received cord blood as the stem cell source. Fifty-five patients relapsed at a median of 231 days after transplantation. The estimated 5-year probabilities of relapse-free survival, relapse, and nonrelapse mortality were 47%, 30%, and 29%, respectively. By multivariate analyses, transplantation while in CR1 was the most important predictor of successful transplantation. Pretransplantation evidence of minimal residual disease, especially as detected by flow cytometric analysis, was associated with both lower overall survival and lower relapse-free survival. Compared with a similar cohort of patients undergoing transplantation between 1990 and 1997, overall survival was similar for patients undergoing transplantation in CR1, with lower nonrelapse mortality being offset by higher rates of relapse in patients who underwent transplantation more recently.

Extracorporeal photopheresis in addition to pentostatin in conditioning for canine hematopoietic cell transplantation: role in engraftment

Extracorporeal photopheresis (ECP) and the purine analog pentostatin exert potent immunomodulatory effects, but have not been evaluated for their ability to enhance engraftment of hematopoietic stem cells. We evaluated, in a canine model of dog leukocyte antigen (DLA)-identical hematopoietic cell transplantation (HCT), whether ECP in combination with pentostatin could enhance engraftment using a nonmyeloablative regimen consisting of 100 cGy TBI and postgrafting immunosuppression with mycophenolate mofetil and CYA. We have shown previously that with 100 cGy TBI alone as conditioning, all of the six dogs rejected their grafts 2-12 weeks after HCT. With the addition of pentostatin to 100 cGy TBI, 6 of 10 dogs rejected their graft. We now tested the additional use of ECP alone (n=2) or ECP and 3-6 doses of pentostatin (n=7) before 100 cGy TBI and HCT. Eight out of nine dogs rejected their grafts within 6-11 weeks after HCT. Compared with data without ECP, we failed to demonstrate a positive impact of the use of either ECP or pentostatin for prevention of rejection.

Reduced mortality after allogeneic hematopoietic-cell transplantation

BACKGROUND

Over the past decade, advances have been made in the care of patients undergoing transplantation. We conducted a study to determine whether these advances have improved the outcomes of transplantation.

METHODS

We analyzed overall mortality, mortality not preceded by relapse, recurrent malignant conditions, and the frequency and severity of major complications of transplantation, including graft-versus-host disease (GVHD) and hepatic, renal, pulmonary, and infectious complications, among 1418 patients who received their first allogeneic transplants at our center in Seattle in the period from 1993 through 1997 and among 1148 patients who received their first allogeneic transplants in the period from 2003 through 2007. Components of the Pretransplant Assessment of Mortality (PAM) score were used in regression models to adjust for the severity of illness at the time of transplantation.

RESULTS

In the 2003-2007 period, as compared with the 1993-1997 period, we observed significant decreases in mortality not preceded by relapse, both at day 200 (by 60%) and overall (by 52%), the rate of relapse or progression of a malignant condition (by 21%), and overall mortality (by 41%), after adjustment for components of the PAM score. The results were similar when the analyses were limited to patients who received myeloablative conditioning therapy. We also found significant decreases in the risk of severe GVHD; disease caused by viral, bacterial, and fungal infections; and damage to the liver, kidneys, and lungs.

CONCLUSIONS

We found a substantial reduction in the hazard of death related to allogeneic hematopoietic-cell transplantation, as well as increased long-term survival, over the past decade. Improved outcomes appear to be related to reductions in organ damage, infection, and severe acute GVHD. (Funded by the National Institutes of Health.).

Efficacy and safety of gemcitabine, carboplatin, dexamethasone, and rituximab in patients with relapsed/refractory lymphoma: a prospective multi-center phase II study by the Puget Sound Oncology Consortium

We conducted a multi-center phase II trial of gemcitabine (G), carboplatin (C), dexamethasone (D), and rituximab (R) in order to examine its safety and efficacy as an outpatient salvage regimen for lymphoma. Fifty-one patients received 2-4 21-day cycles of G (1000 mg/m(2), days 1 and 8), C (AUC = 5, day 1), D (40 mg, daily days 1-4), and R (375 mg/m(2), day 8 for CD20-positive disease) and were evaluable for response. Characteristics included: median age 58 years (19-79 years), stage III/IV 88%, elevated LDH 33%, median prior therapies 2, prior stem cell transplant 12%, chemoresistant 62%, median prior remission duration 2.5 months. The overall and complete response rates were 67% (95% confidence interval [CI] 54-80%) and 31% (95% CI 19-44%), respectively, with activity seen in a broad variety of histologies. Responses occurred in 16 of 17 (94%, 95% CI 83-100%) transplant-eligible patients and 15 of 28 (54%, 95% CI 34-71%) with chemoresistant disease. The median CD34 yield in patients attempting peripheral blood stem cell (PBSC) collection following this regimen was 10.9 x 10(6) CD34+ cells/kg (range 5.0-24.1 x 10(6)). Hematologic toxicity was common, but febrile neutropenia (2.5%) and grade 4 non-hematologic adverse events (n = 2) were rare, with no treatment-related deaths. GCD(R) is a safe and effective outpatient regimen for relapsed lymphoma, and successfully mobilizes PBSCs.

Allogeneic hematopoietic cell transplantation for chronic myelomonocytic leukemia: relapse-free survival is determined by karyotype and comorbidities

Hematopoietic cell transplantation (HCT) offers potentially curative therapy for chronic myelomonocytic leukemia (CMML). We evaluated HCT outcomes in 85 patients with CMML, 1.0-69.1 (median 51.7) years of age, with follow-up extending to 19 years. CMML was considered de novo in 71 and secondary in 14 patients. Conditioning regimens were of various intensities. Thirty-eight patients had related (34 HLA identical), and 47 (39 HLA matched) unrelated donors. The source of stem cells was marrow in 32 and peripheral blood progenitor cells in 53 patients. Acute graft-versus-host disease (aGVHD) grades II-IV occurred in 72% and chronic GVHD (cGVHD) in 26% of patients. Relapse incidence was 27% at 10 years. Relapse correlated with increasing scores by the MD Anderson prognostic score (P = .01). The major causes of death were relapse and infections ±GVHD. Progression-free survival (PFS) was 38% at 10 years. Mortality was negatively correlated with pre-HCT hematocrit (P = .007), and increased with high-risk cytogenetics (P = .02), higher HCT Comorbidity Index (P = .0008), and increased age (P = .02). WHO classification did not statistically significantly affect outcome. Thus, a proportion of patients with CMML have lasting remissions following allogeneic HCT and appear to be cured of their disease.

Blood and gastric FOXP3+ T cells are not decreased in human gastric graft-versus-host disease

Previous studies suggest regulatory T cells (Tregs) inhibit graft-versus-host disease (GVHD) in mouse and human hematopoietic cell transplant (HCT) recipients. As the gastrointestinal tract represents one of the most common and severe sites of GVHD-related tissue damage, we sought to determine whether a deficit in circulating or gastric mucosal Treg numbers correlates with the clinical onset of gastric GVHD. We used the marker FOXP3 to quantify Tregs in blood and in gastric antral biopsies in a cohort of 60 allogeneic HCT recipients undergoing endoscopy at a single center to evaluate symptoms suspicious for gastrointestinal GVHD. We show for the first time in the gastric mucosa and, contrary to existing reports, in the blood, that the percent of T cells expressing FOXP3 is at least as high in the presence as in the absence of GVHD involving the upper gut. There was no correlation of Treg frequency with the histologic or clinical severity of gastrointestinal GVHD. We conclude that Treg depletion is not a central feature in the pathogenesis of gastric GVHD in humans.

Comparison of matched unrelated and matched related donor myeloablative hematopoietic cell transplantation for adults with acute myeloid leukemia in first remission

Hematopoietic cell transplantation (HCT) from a matched related donor (MRD) benefits many adults with acute myeloid leukemia (AML) in first complete remission (CR1). The majority of patients do not have such a donor, however, requiring use of an alternative donor if HCT is undertaken. We retrospectively analyzed 226 adult AML CR1 patients undergoing myeloablative unrelated donor (URD) (10/10 match, n=62; ≤9/10, n=29) or MRD (n=135) HCT from 1996–2007. Five-year estimates of overall survival (OS), relapse, and non-relapse mortality (NRM) were 57.9%, 29.7%, and 16.0%, respectively. Failure for each of these outcomes was slightly higher for 10/10 URD than MRD HCT, although statistical significance was not reached for any endpoint. The adjusted hazard ratios (HR) were 1.43 (0.89–2.30, p=0.14) for overall mortality, 1.17 (0.66–2.08, p=0.60) for relapse, and 1.79 (0.86–3.74, p=0.12) for NRM, respectively, and the adjusted odds ratio (OR) for grades 2–4 acute graft-versus-host disease was 1.50 (0.70–3.24, p=0.30). Overall mortality among 9/10 and 10/10 URD recipients was similar (adjusted HR=1.16 [0.52–2.61], p=0.71). These data indicate that URD HCT can provide long-term survival for CR1 AML; outcomes for 10/10 URD HCT, and possibly 9/10 URD HCT, suggest that this modality should be considered in the absence of a suitable MRD.

HLA-allele matched unrelated donors compared to HLA-matched sibling donors: role of cell source and disease risk category

To determine whether the risks of allogeneic transplantation are different when the donor is a fully matched unrelated donor (MUD; based on 10/10 HLA alleles) compared to an HLA-identical sibling, we performed a retrospective analysis of 1448 patients with high-risk or advanced hematologic malignancies given T-replete grafts after myeloablative conditioning. No statistically significant differences were found between recipients of a matched sibling donor (MSD) and 10/10 MUD in survival, disease-free survival (DFS), and nonrelapse mortality (NRM) for patients with high-risk disease or those given bone marrow as a graft source. However, for patients with intermediate-risk disease receiving peripheral blood grafts, we observed higher NRM and lower overall survival (OS) in the 10/10 MUD group compared to the MSD cohort. Graft-versus-host disease (GVHD) was higher in the MUD group compared to the MSD group. These results suggest that if a patient has high-risk disease and an MSD is not available, selection of an HLA-allele-matched MUD may provide similar OS and DFS, and therefore lack of an MSD in and of itself should not preclude such a patient from undergoing transplantation. However, for patients with intermediate-risk disease, transplantation with peripheral blood from a 10/10 MUD is associated with lower survival than an MSD.

Pharmacological treatment of obstructive sleep apnea with a combination of pseudoephedrine and domperidone

OBJECTIVES

To determine the effect of the drug combination domperidone and pseudoephedrine on nocturnal oximetry measurements and daytime sleepiness in patients with obstructive sleep apnea.

METHODS

We recruited patients with severe snoring and apneic episodes willing to undergo repeated nocturnal oximetry testing. Following baseline clinical history, Epworth Sleepiness Scale administration, and home overnight nocturnal oximetry, patients were started on weight-adjusted doses of domperidone and pseudoephedrine. Follow-up oximetry studies were performed at the patient's convenience. On the final visit, a repeat clinical history, Epworth score, and oximetry were obtained.

RESULTS

Seventeen of 23 patients noted disappearance of snoring and apneic episodes. Another 2 patients reported improvement in snoring and no apneic episodes. All but one patient had a decrease in Epworth scores (mean decrease 9.4 (95% CI, 6.8-12.1, p < 0.0001). Mean oxygen saturation (2.5; 95% Cl, 0.66-4.41, p = 0.008), percent time with oxygen saturation < 90% (14.8; 95% CI, 24.4 to 5.2, p = 0.003), and the 4% oxygen desaturation index (18.2; 95% CI, 27.3 to 9.1, p < 0.0001) improved significantly. No adverse effects of treatment were noted.

CONCLUSIONS

The combination of domperidone and pseudoephedrine improved self reported snoring and sleepiness, and may have improved apneic episodes and sleep-related nocturnal oxygen desaturation in patients with obstructive sleep apnea provided the proportion of time spent asleep did not diminish. This drug combination warrants further study as a treatment for obstructive sleep apnea.

KEYWORDS

Obstructive sleep apnea; oximetry; sleepiness; domperidone; pseudoephedrine; pharmacotherapy; desaturation; treatment

CITATION

Larrain A; Kapur VK; Gooley TA; Pope CE. Pharmacological treatment of obstructive sleep apnea with a combination of pseudoephedrine and domperidone.

Influence of oral beclomethasone dipropionate on early non-infectious pulmonary outcomes after allogeneic hematopoietic cell transplantation: results from two randomized trials

Early non-infectious pulmonary complications represent a significant cause of mortality after hematopoietic cell transplantation (HCT). We tested the hypothesis that oral beclomethasone dipropionate (BDP) is effective for preventing early non-infectious pulmonary complications after allogeneic HCT. We retrospectively reviewed the medical records of 120 patients, 60 in each treatment arm, to identify non-infectious and infectious pulmonary events and pulmonary function test results from all patients who participated in two randomized trials of oral BDP for treatment of acute gastrointestinal GVHD. 17-Beclomethasone monopropionate (17-BMP), the active metabolite of BDP, was evaluated in blood from the right atrium in four patients. Thirty-three of 42 (79%) placebo-treated patients experienced a decrease of the DL(CO) from pretransplant to day 80 after transplant, compared with 27 of 49 (55%) BDP-treated patients (P=0.02). In the first 200 days after randomization, there were no cases of non-infectious pulmonary complications in BDP-treated patients, vs four cases among placebo-treated patients (P=0.04). Levels of 17-BMP were detected in atrial blood at steady state. Delivery of a potent glucocorticoid such as 17-BMP to the pulmonary artery after oral dosing of BDP may be useful in modulating pulmonary inflammation and preventing the development of non-infectious pulmonary complications after allogeneic HCT.

Adjusted estimates for time-to-event endpoints

In the analysis of retrospective data or when interpreting results from a single-arm phase II clinical trial relative to historical data, it is often of interest to show plots summarizing time-to-event outcomes comparing treatment groups. If the groups being compared are imbalanced with respect to factors known to influence outcome, these plots can be misleading and seemingly incompatible with results obtained from a regression model that accounts for these imbalances. We consider ways in which covariate information can be used to obtain adjusted curves for time-to-event outcomes. We first review a common model-based method and then suggest another model-based approach that is not as reliant on model assumptions. Finally, an approach that is partially model free is suggested. Each method is applied to an example from hematopoietic cell transplantation.

High-dose therapy and autologous stem cell transplantation for chemoresistant Hodgkin lymphoma: the Seattle experience

BACKGROUND

High-dose therapy (HDT) with autologous stem cell transplantation (ASCT) is the standard treatment for patients with chemosensitive relapsed/refractory Hodgkin lymphoma (HL), but this therapy is commonly denied to patients with resistant disease. We explored the utility of HDT and ASCT for chemoresistant HL because there are few established therapies for these patients.

METHODS

Sixty-four chemoresistant HL patients underwent HDT followed by ASCT at our center. Baseline characteristics included median age = 35 years (range, 14-59 years), stage III/IV = 49 (77%), nodular sclerosis histology = 51 (80%), and prior radiation = 32 (50%). Twenty-six patients (41%) received total body irradiation (TBI)-based regimens, and 38 (59%) underwent non-TBI conditioning.

RESULTS

The estimated 5-year overall survival (OS) and progression-free survival (PFS) were 31% and 17%, respectively (median follow-up = 4.2 years). Multivariate analysis only identified year of transplant as independently associated with improved OS (P = .008) and PFS (P = .04), with patients receiving transplants in later years having better outcome. The probabilities of 3-year PFS for patients receiving transplants during 1986 to 1989, 1990 to July 1993, August 1993 to 1999, and 2000 to 2005 were 9%, 21%, 33%, and 31%, respectively.

CONCLUSIONS

These data suggest that HDT and ASCT may result in prolonged remissions and survival for a subset of chemoresistant HL patients, with improved outcomes in patients receiving transplants more recently.

HLA-haploidentical bone marrow transplantation for hematologic malignancies using nonmyeloablative conditioning and high-dose, posttransplantation cyclophosphamide

We evaluated the safety and efficacy of high-dose, posttransplantation cyclophosphamide (Cy) to prevent graft rejection and graft-versus-host disease (GVHD) after outpatient nonmyeloablative conditioning and T cell-replete bone marrow transplantation from partially HLA-mismatched (haploidentical) related donors. Patients with advanced hematologic malignancies (n = 67) or paroxysmal nocturnal hemoglobinuria (n = 1) received Cy 50 mg/kg i.v. on day 3 (n = 28) or on days 3 and 4 (n = 40) after transplantation. The median times to neutrophil (>500/microL) and platelet recovery (>20,000/microL) were 15 and 24 days, respectively. Graft failure occurred in 9 of 66 (13%) evaluable patients, and was fatal in 1. The cumulative incidences of grades II-IV and grades III-IV acute (aGVHD) by day 200 were 34% and 6%, respectively. There was a trend toward a lower risk of extensive chronic GVHD (cGVHD) among recipients of 2 versus 1 dose of posttransplantation Cy (P = .05), the only difference between these groups. The cumulative incidences of nonrelapse mortality (NRM) and relapse at 1 year were 15% and 51%, respectively. Actuarial overall survival (OS) and event-free survival (EFS) at 2 years after transplantation were 36% and 26%, respectively. Patients with lymphoid malignancies had an improved EFS compared to those with myelogenous malignancies (P = .02). Nonmyeloablative HLA-haploidentical BMT with posttransplantation Cy is associated with acceptable rates of fatal graft failure and severe aGVHD or cGVHD.

HLA-haploidentical bone marrow transplantation for hematologic malignancies using nonmyeloablative conditioning and high-dose, posttransplantation cyclophosphamide

We evaluated the safety and efficacy of high-dose, posttransplantation cyclophosphamide (Cy) to prevent graft rejection and graft-versus-host disease (GVHD) after outpatient nonmyeloablative conditioning and T cell-replete bone marrow transplantation from partially HLA-mismatched (haploidentical) related donors. Patients with advanced hematologic malignancies (n = 67) or paroxysmal nocturnal hemoglobinuria (n = 1) received Cy 50 mg/kg i.v. on day 3 (n = 28) or on days 3 and 4 (n = 40) after transplantation. The median times to neutrophil (>500/microL) and platelet recovery (>20,000/microL) were 15 and 24 days, respectively. Graft failure occurred in 9 of 66 (13%) evaluable patients, and was fatal in 1. The cumulative incidences of grades II-IV and grades III-IV acute (aGVHD) by day 200 were 34% and 6%, respectively. There was a trend toward a lower risk of extensive chronic GVHD (cGVHD) among recipients of 2 versus 1 dose of posttransplantation Cy (P = .05), the only difference between these groups. The cumulative incidences of nonrelapse mortality (NRM) and relapse at 1 year were 15% and 51%, respectively. Actuarial overall survival (OS) and event-free survival (EFS) at 2 years after transplantation were 36% and 26%, respectively. Patients with lymphoid malignancies had an improved EFS compared to those with myelogenous malignancies (P = .02). Nonmyeloablative HLA-haploidentical BMT with posttransplantation Cy is associated with acceptable rates of fatal graft failure and severe aGVHD or cGVHD.

Myeloablative 131I-tositumomab radioimmunotherapy in treating non-Hodgkin's lymphoma: comparison of dosimetry based on whole-body retention and dose to critical organ receiving the highest dose

Myeloablative radioimmunotherapy using (131)I-tositumomab (anti-CD20) monoclonal antibodies is an effective therapy for B-cell non-Hodgkin's lymphoma. The amount of radioactivity for radioimmunotherapy may be determined by several methods, including those based on whole-body retention and on dose to a limiting normal organ. The goal of each approach is to deliver maximal myeloablative amounts of radioactivity within the tolerance of critical normal organs.

METHODS

Records of 100 consecutive patients who underwent biodistribution and dosimetry evaluation after tracer infusion of (131)I-tositumomab before radioimmunotherapy were reviewed. We assessed organ and tissue activities over time by serial gamma-camera imaging to calculate radiation-absorbed doses. Organ volumes were determined from CT scans for organ-specific dosimetry. These dose estimates helped us to determine therapy on the basis of projected dose to the critical normal organ receiving a maximum tolerable radiation dose. We compared organ-specific dosimetry for treatment planning with the whole-body dose-assessment method by retrospectively analyzing the differences in projected organ-absorbed doses and their ratios.

RESULTS

Mean organ doses per unit of administered activity (mGy/MBq) estimated by both methods were 0.33 for liver and 0.33 for lungs by the whole-body method and 1.52 for liver and 1.74 for lungs by the organ-specific method (P=0.0001). The median differences between methods were 0.92 mGy/MBq (range, 0.36-2.2 mGy/MBq) for lungs, 0.82 mGy/MBq (range, 0.28-1.67 mGy/MBq) for liver, and -0.01 mGy/MBq (range, -0.18-0.16 mGy/MBq) for whole body. The median ratios of the treatment activities based on limiting normal-organ dose were 5.12 (range, 2.33-10.01) for lungs, 4.14 (range, 2.16-6.67) for liver, and 0.94 (range, 0.79-1.22) for whole body. We found substantial differences between the dose estimated by the 2 methods for liver and lungs (P=0.0001).

CONCLUSION

Dosimetry based on whole-body retention will underestimate the organ doses, and a preferable approach is to evaluate organ-specific doses by accounting for actual radionuclide biodistribution. Myeloablative treatments based on the latter approach allow administration of the maximum amount of radioactivity while minimizing toxicity.

Mapping MHC-resident transplantation determinants

Graft-versus-host disease (GVHD) accounts for increased morbidity and mortality after HLA-identical unrelated hematopoietic cell transplantation (HCT). To test the hypothesis that the major histocompatibility complex (MHC) encodes functional variation other than the classical HLA genes, we measured risks associated with donor-recipient MHC microsatellite (Msat) marker mismatching in 819 HCT recipients and their HLA-A, -B, -C, -DRB1, and -DQB1 allele-matched unrelated donors. Suggestive trends of association with transplant outcome were observed for 5 Msats. Donor-recipient mismatching for the extended class I D6S105, class III D6S2787, and class II D6S2749 markers was each associated with an increased risk of death (hazard ratio, 1.32; 95% confidence interval, 1.02-1.71; P=.03; hazard ratio, 1.26; 95% confidence interval, 1.03-1.53; P=.02; hazard ratio, 1.37; 95% confidence interval, 1.08-1.72; P=.007, respectively) whereas mismatching for the class I D6S2811 marker was associated with a decreased risk of death (hazard ratio, 0.80; 95% confidence interval, 0.66-0.98; P=.03). Mismatching for the class I D6S265 marker was associated with a decreased risk of grades III-IV acute GVHD (odds ratio, 0.67; 95% confidence interval, 0.45-0.98; P=.04). These results suggest that Msats may be informative for mapping MHC-resident genetic variation of clinical importance in HCT.

Mutation at the polymerase active site of mouse DNA polymerase delta increases genomic instability and accelerates tumorigenesis

Mammalian DNA polymerase delta (Pol delta) is believed to replicate a large portion of the genome and to synthesize DNA in DNA repair and genetic recombination pathways. The effects of mutation in the polymerase domain of this essential enzyme are unknown. Here, we generated mice harboring an L604G or L604K substitution in highly conserved motif A in the polymerase active site of Pol delta. Homozygous Pold1(L604G/L604G) and Pold1(L604K/L604K) mice died in utero. However, heterozygous animals were viable and displayed no overall increase in disease incidence, indicative of efficient compensation for the defective mutant polymerase. The life spans of wild-type and heterozygous Pold1(+/L604G) mice did not differ, while that of Pold1(+/L604K) mice was reduced by 18%. Cultured embryonic fibroblasts from the heterozygous strains exhibited comparable increases in both spontaneous mutation rate and chromosome aberrations. We observed no significant increase in cancer incidence; however, Pold1(+/L604K) mice bearing histologically diagnosed tumors died at a younger median age than wild-type mice. Our results indicate that heterozygous mutation at L604 in the polymerase active site of DNA polymerase delta reduces life span, increases genomic instability, and accelerates tumorigenesis in an allele-specific manner, novel findings that have implications for human cancer.

CD33 expression and P-glycoprotein-mediated drug efflux inversely correlate and predict clinical outcome in patients with acute myeloid leukemia treated with gemtuzumab ozogamicin monotherapy

Gemtuzumab ozogamicin (GO) contains an anti-CD33 antibody to facilitate uptake of a toxic calicheamicin-gamma(1) derivative. While recent in vitro data demonstrated a quantitative relationship between CD33 expression and GO cytotoxicity, previous correlative studies failed to identify a significant association between CD33 expression and clinical outcome. Studying patients undergoing GO monotherapy for relapsed acute myeloid leukemia (AML), we now find that AML blasts of responders have a significantly higher mean CD33 level and lower P-glycoprotein (Pgp) activity compared with nonresponders. CD33 expression and Pgp activity are inversely correlated. While both variables are associated with outcome, Pgp remains significantly associated with outcome even after adjusting for CD33, whereas CD33 does not show such an association after adjusting for Pgp. The inverse relationship between CD33 and Pgp suggests a maturation-stage-dependent expression of both proteins, and offers the rationale for using cell differentiation-promoting agents to enhance GO-induced cytotoxicity.

Efficacy of communication skills training for giving bad news and discussing transitions to palliative care

BACKGROUND

Few studies have assessed the efficacy of communication skills training for postgraduate physician trainees at the level of behaviors. We designed a residential communication skills workshop (Oncotalk) for medical oncology fellows. The intervention design built on existing successful models by teaching specific communication tasks linked to the patient's trajectory of illness. This study evaluated the efficacy of Oncotalk in changing observable communication behaviors.

METHODS

Oncotalk was a 4-day residential workshop emphasizing skills practice in small groups. This preintervention and postintervention cohort study involved 115 medical oncology fellows from 62 different institutions during a 3-year study. The primary outcomes were observable participant communication skills measured during standardized patient encounters before and after the workshop in giving bad news and discussing transitions to palliative care. The standardized patient encounters were audiorecorded and assessed by blinded coders using a validated coding system. Before-after comparisons were made using each participant as his or her own control.

RESULTS

Compared with preworkshop standardized patient encounters, postworkshop encounters showed that participants acquired a mean of 5.4 bad news skills (P<.001) and a mean of 4.4 transitions skills (P<.001). Most changes in individual skills were substantial; for example, in the bad news encounter, 16% of participants used the word "cancer" when giving bad news before the workshop, and 54% used it after the workshop (P<.001). Also in the bad news encounter, blinded coders were able to identify whether a standardized patient encounter occurred before or after the workshop in 91% of the audiorecordings.

CONCLUSION

Oncotalk represents a successful teaching model for improving communication skills for postgraduate medical trainees.

High-dose [131I]tositumomab (anti-CD20) radioimmunotherapy and autologous hematopoietic stem-cell transplantation for adults > or = 60 years old with relapsed or refractory B-cell lymphoma

PURPOSE

The majority of patients with relapsed or refractory B-cell non-Hodgkin's lymphoma (NHL) are older than 60 years, yet they are often denied potentially curative high-dose therapy and autologous stem-cell transplantations (ASCT) because of the risk of excessive treatment-related morbidity and mortality. Myeloablative anti-CD20 radioimmunotherapy (RIT) can deliver curative radiation doses to tumor sites while limiting exposure to normal organs and may be particularly suited for older adults requiring high-dose therapy.

PATIENTS AND METHODS

Patients older than 60 years with relapsed B-cell NHL (B-NHL) received infusions of tositumomab anti-CD20 antibody labeled with 185 to 370 Mbq (5 to 10 mCi) [131I]-tracer for dosimetry purposes followed 10 days later by individualized therapeutic infusions of [131I]tositumomab (median, 19.4 Gbq [525 mCi]; range, 12.1 to 42.7 Gbq [328 to 1,154 mCi]) to deliver 25 to 27 Gy to the critical normal organ receiving the highest radiation dose. ASCT was performed approximately 2 weeks after therapy.

RESULTS

Twenty-four patients with a median age of 64 years (range, 60 to 76 years), who had received a median of four prior regimens (range, two to 14 regimens), were treated. Thirteen patients (54%) had chemotherapy-resistant disease. The estimated 3-year overall and progression-free survival rates were 59% and 51%, respectively, with a median follow-up of 2.9 years (range, 1 to 6 years). All patients experienced expected myeloablation with engraftment of platelets (> or = 20 K/microL) and neutrophils ( 500/microL), occurring at a median of 9 and 15 days after ASCT, respectively. There were no treatment-related deaths, and only two patients experienced grade 4 nonhematologic toxicity.

CONCLUSION

Myeloablative RIT and ASCT is a safe and effective therapeutic option for older adults with relapsed B-NHL.

MHC haplotype matching for unrelated hematopoietic cell transplantation

BACKGROUND

Current criteria for the selection of unrelated donors for hematopoietic cell transplantation (HCT) include matching for the alleles of each human leukocyte antigen (HLA) locus within the major histocompatibility complex (MHC). Graft-versus-host disease (GVHD), however, remains a significant and potentially life-threatening complication even after HLA-identical unrelated HCT. The MHC harbors more than 400 genes, but the total number of transplantation antigens is unknown. Genes that influence transplantation outcome could be identified by using linkage disequilibrium (LD)-mapping approaches, if the extended MHC haplotypes of the unrelated donor and recipient could be defined.

METHODS AND FINDINGS

We isolated DNA strands extending across 2 million base pairs of the MHC to determine the physical linkage of HLA-A, -B, and -DRB1 alleles in 246 HCT recipients and their HLA-A, -B, -C, -DRB1, -DQB1 allele-matched unrelated donors. MHC haplotype mismatching was associated with a statistically significantly increased risk of severe acute GVHD (odds ratio 4.51; 95% confidence interval [CI], 2.34-8.70, p < 0.0001) and with lower risk of disease recurrence (hazard ratio 0.45; 95% CI, 0.22-0.92, p = 0.03).

CONCLUSIONS

The MHC harbors genes that encode unidentified transplantation antigens. The three-locus HLA-A, -B, -DRB1 haplotype serves as a proxy for GVHD risk among HLA-identical transplant recipients. The phasing method provides an approach for mapping novel MHC-linked transplantation determinants and a means to decrease GVHD-related morbidity after HCT from unrelated donors.

Gastrointestinal graft-versus-host disease in recipients of autologous hematopoietic stem cells: incidence, risk factors, and outcome

Graft-versus-host disease (GVHD) is seen in skin, intestinal mucosa, and liver after autologous stem cell transplantation. We reviewed 681 consecutive patients to estimate the probability of gastrointestinal (GI) GVHD, response to treatment, risk factors for development, and effect on survival. GI GVHD was defined by persistent symptoms, mucosal abnormalities at endoscopy, and histology showing apoptotic crypt cells with or without lymphoid infiltrates. The proportion of patients with GI GVHD was 90/681 (13%). Nausea and vomiting occurred in 90% and diarrhea in 40%. The mean time to developing symptoms was day +15, that to histologically proven diagnosis was day +42, and that to starting prednisone treatment was day +45 after stem cell infusion. Treatment with a short course of prednisone effected durable responses in 79% of patients, and an additional 18% responded to a second course of prednisone. A multivariable logistic regression model demonstrated that the combined factor of a diagnosis of breast cancer or hematologic malignancy and female sex was statistically significantly associated with the probability of GI GVHD (P = .003). Survival in patients with GI GVHD was not statistically different than that in those without GVHD. We conclude that women with breast cancer or hematologic malignancy are more likely to develop GI GVHD after autologous transplantation, and that treatment with prednisone was effective.

Risk of ruling out severe acute respiratory syndrome by ruling in another diagnosis: variable incidence of atypical bacteria coinfection based on diagnostic assays

BACKGROUND

Severe acute respiratory syndrome (SARS) caused the first epidemic of the 21st century and continues to threaten the global community.

OBJECTIVE

To assess the incidence of coinfection in patients confirmed to have SARS-associated coronavirus (SARS-CoV) infection, and thus, to determine the risk of ruling out SARS by ruling in another diagnosis.

METHODS

The present report is a retrospective study evaluating the incidence and impact of laboratory-confirmed SARS-CoV and other pulmonary pathogens in 117 patients. These patients were evaluated in a Toronto, Ontario, community hospital identified as the epicentre for the second SARS outbreak.

RESULTS

Coinfection with other pulmonary pathogens occurred in patients with SARS. Seventy-three per cent of the patient population evaluated had laboratory-confirmed SARS-CoV infection. Serology showing acute or recent Chlamydophila pneumoniae or Mycoplasma pneumoniae infection revealed an incidence of 30% and 9%, respectively, in those with SARS. These rates are similar to previously published studies on coinfection in pneumonia. All nucleic acid diagnostic assays were negative for C pneumoniae and M pneumoniae in respiratory samples from patients with SARS having serological evidence for these atypical pathogens.

CONCLUSIONS

Diagnostic assays for well-recognized pulmonary pathogens have limitations, and ruling out SARS-CoV by ruling in another pulmonary pathogen carries significant risk. Despite positive serology for atypical pathogens, in a setting where clinical suspicion for SARS is high, specific tests for SARS should be performed to confirm or exclude a diagnosis.

Imatinib therapy prior to myeloablative allogeneic stem cell transplantation

It is unknown whether imatinib prior to myeloablative haematopoietic stem cell transplantation (HSCT) increases transplant-related toxicity. Among the side effects induced by imatinib, myelosuppression and liver injury might worsen HSCT outcomes. We retrospectively analysed engraftment, liver toxicity, acute graft-versus-host disease (aGVHD) incidence and 100-day mortality in 30 patients with BCR/ABL-positive leukaemias who received imatinib before HSCT and compared results of 48 age-matched controls who did not receive preceding imatinib. Both neutrophil and platelet engraftment occurred more rapidly among imatinib patients but the differences adjusted for Gratwohl scale were not statistically significant (P = 0.18 and 0.22, respectively). The adjusted hazards of having liver function tests (LFTs) >1.5 normal increased and the adjusted durations of elevated LFTs were not significantly different. The estimated adjusted difference in mean peak bilirubin values was also not significantly different (P = 0.48). However, the adjusted hazard of increased creatinine >1.5 normal was significantly higher in the imatinib group (HR = 4.09, P = 0.02). The adjusted odds of grades II-IV aGVHD were similar in both groups (OR = 0.86, P = 0.78), and while the adjusted odds of 100-day mortality were lower among imatinib patients, the difference was not significant (OR = 0.65, P = 0.60). These data do not provide any evidence that imatinib preceding HSCT increases acute transplant-related toxicities.

Allogeneic hematopoietic cell transplantation for infants with acute lymphoblastic leukemia

The role of transplantation in infants with acute lymphoblastic leukemia (ALL) is not defined. We analyzed results of 40 infants diagnosed before age 12 months who received a hematopoietic cell transplant (HCT) between July 1982 and February 2003 in first complete remission (CR1; n = 17), CR2/3 (n = 7), or relapse (n = 16). Patients were conditioned with cyclophosphamide with total body irradiation (n = 39) or busulfan (n = 1). Donors were matched related (n = 8), mismatched related (n = 16), or unrelated (n = 16). Graft-versus-host disease (GVHD) prophylaxis was methotrexate or cyclosporine (n = 7) or methotrexate plus cyclosporine (n = 33). Thirty-nine patients engrafted, 20 developed acute GVHD, and 7 developed chronic GVHD. Sixteen patients relapsed and 7 died of other causes. Patients in CR1 had disease-free survival (DFS) of 76% compared with 45% for CR2/CR3 and 8% for relapse (P < .001). Of 33 patients with cytogenetic data, 26 (79%) had MLL gene rearrangement. Fourteen of these 26 were in CR1 and 11 survive in remission. Outcome was associated with phase of disease, but having the MLL gene was not a factor predictive of outcome. Late effects included growth and other hormone deficiencies. These data demonstrate that infants with ALL and MLL gene have excellent DFS when they received transplants in CR1, and consideration for transplantation in CR1 is warranted.

Outcome of allogeneic bone marrow transplantation for children with advanced acute myeloid leukemia

Allogeneic bone marrow transplantation (BMT) may offer the only chance of cure for children with acute myeloid leukemia (AML) in second complete remission (CR2) or with relapsed disease, but the outcome of these patients has not been clearly defined. We conducted a retrospective study of 58 children, median age 7.4 years (range 0.8-17.3), who received matched related or unrelated BMT at our institution for AML in CR2 (n = 12), in untreated first relapse (n = 11) or with refractory disease (n = 35), to identify risk factors associated with disease-free survival (DFS). Life threatening to fatal regimen-related toxicity was observed in 22% of patients. Estimates of DFS at 5 years (95% confidence interval) for patients in CR2, with untreated first relapse and refractory disease were 58% (27-80%), 36% (11-63%) and 9% (2-21%), respectively. Non-relapse mortality estimates were 0%, 27% (0-54%) and 17% (5-30%), and relapse estimates were 42% (14-70%), 36% (8-65%) and 74% (60-89%), respectively. Advanced disease phase and cytogenetic abnormalities at the time of transplantation were each associated with decreased DFS and increased relapse in multivariable regression models. Survival for children transplanted in CR2 or untreated first relapse is higher than that previously reported, but relapse remains the major cause of treatment failure regardless of disease stage.

Serum bilirubin levels and mortality after myeloablative allogeneic hematopoietic cell transplantation

Many patients who undergo hematopoietic cell transplantation experience liver injury. We examined the association of serum bilirubin levels with nonrelapse mortality by day +200, testing the hypothesis that the duration of jaundice up to a given point in time provides more prognostic information than either the maximum bilirubin value or the value at that point in time. We studied 1,419 consecutive patients transplanted from allogeneic donors. Total serum bilirubin values up to day +100, death, or relapse were retrieved-along with nonrelapse mortality by day +200 as an outcome measure--using Cox regression models with each bilirubin measure modeled as a time-dependent covariate. The bilirubin value at a particular point in time provided the best fit to the model for mortality. With bilirubin at a point in time modeled as an 8th-degree polynomial, an increase in bilirubin from 1 to 3 mg/dL is associated with a mortality hazard ratio of 6.42. An increase from 4 to 6 mg/dL yields a hazard ratio of 2.05, and an increase from 10 to 12 mg/dL yields a hazard ratio of 1.17. Among patients who were deeply jaundiced, survival was related to the absence of multiorgan failure and to higher platelet counts. In conclusion, the value of total serum bilirubin at a particular point in time after transplant carries more informative prognostic information than does the maximum or average value up to that point in time. The increase in mortality for a given increase in bilirubin value is larger when the starting value is lower.

Allogeneic bone marrow transplantation in children with myelodysplastic syndrome or juvenile myelomonocytic leukemia: the Seattle experience

The purpose of this study was to evaluate the role of allogeneic bone marrow transplantation (BMT) in children with myelodysplastic syndrome (MDS). In total, 94 consecutive pediatric patients with MDS received an allogeneic BMT from 1976 to 2001 for refractory anemia (RA) (n=25), RA with ringed sideroblasts (RARS) (n=2), RA with excess blasts (RAEB) (n=20), RAEB in transformation (RAEB-T) (n=14), juvenile myelomonocytic leukemia (JMML) (n=32) or chronic myelomonocytic leukemia (CMML) (n=1). The estimated 3-year probabilities of survival, event-free survival (EFS), nonrelapse mortality and relapse were 50, 41, 28 and 29%, respectively. Patients with RA/RARS had an estimated 3-year survival of 74% compared to 68% in those with RAEB and 33% in patients with JMML/CMML. In multivariable analysis, patients with RAEB-T or JMML were 3.9 and 3.7 times more likely to die compared to those with RA/RARS and RAEB (P=0.005 and 0.004, respectively). Patients with RAEB-T were 5.5 times more likely to relapse (P=0.01). The median follow-up among the 43 surviving patients is 10 years (range 1-25). We conclude that allogeneic BMT for children with MDS is well tolerated and can be curative.

Disparity for a newly identified minor histocompatibility antigen, HA-8, correlates with acute graft-versus -host disease after haematopoietic stem cell transplantation from an HLA-identical sibling

We recently identified a new minor histocompatibility antigen, termed HA-8, which is presented by human leucocyte antigen (HLA)-A*0201 or HLA-A*0202 and expressed ubiquitously among tissues. A retrospective analysis of 577 Caucasian patients with HLA-A*0201 or A*0202 who had received a haematopoietic stem cell transplant from a human leucocyte antigen (HLA)-identical sibling was conducted to determine whether HA-8 disparity correlated with clinical outcome. HA-8 disparity was detected in 72 recipients, and grades II-IV graft-versus-host disease (GVHD) occurred in 46 (64%), compared with 251 (50%) of the 503 patients without HA-8 disparity. After adjusting for known risk factors for acute GVHD, this difference was statistically significant (odds ratio, 1.8; 95% confidence interval, 1.0-3.1; P = 0.04). However, the hazards of clinical extensive chronic GVHD, overall mortality and recurrent malignancy were not statistically significantly different between the two groups. These data suggest that the increased risk of acute GVHD associated with recipient HA-8 disparity was not sufficient to change other clinical outcomes.

Airflow obstruction after myeloablative allogeneic hematopoietic stem cell transplantation

Despite advances in the management of myeloablative allogeneic hematopoietic stem cell transplants, airflow obstruction (AFO) remains a significant complication. We conducted a 12-year study to examine the recent epidemiology of AFO and its associated mortality. Using the rate of percent predicted FEV1 decline after transplant, we defined AFO as a more than 5% per year decline in percent predicted FEV1 with the lowest post-transplant FEV1/FVC ratio less than 0.8. New obstruction was more frequent than previous estimates (26% overall, 32% among patients with chronic graft-versus-host disease [GVHD]) and was significantly associated with older age at transplant, lower pretransplant FEV1/FVC ratio, history of both acute and chronic GVHD, and respiratory viral infection within the first 100 days after transplant. AFO was associated with significant attributable mortality rates of 9% at 3 years, 12% at 5 years, and 18% at 10 years after transplant, which were much higher for the subpopulation of patients with chronic GVHD (22% at 3 years, 27% at 5 years, and 40% at 10 years). These results suggest that the incidence of AFO may have been underestimated previously, and its presence significantly increases the mortality of long-term survivors of myeloablative allogeneic hematopoietic stem cell transplant patients.

Human herpesvirus 6 reactivation and encephalitis in allogeneic bone marrow transplant recipients

To determine whether receipt of an investigational anti-CD3 monoclonal antibody (BC3) increased the risk of human herpesvirus 6 (HHV-6) reactivation and development of encephalitis in bone marrow transplant (BMT) recipients, persons who had and had not received BC3 were compared. Odds of HHV-6 reactivation were higher among BC3 recipients than among control patients (odds ratio, 2.5; 95% confidence interval [CI], 1.3-4.7). In addition, BC3 recipients were more likely than control patients to develop encephalitis (risk ratio [RR], 3.5; 95% CI, 1.3-9.5), and this association followed a BC3 dose-dependent relationship (P=.03, by Mantel-Haenszel chi(2) test). In a multivariable model, HHV-6 reactivation and receipt of BC3 were associated with increased risk of encephalitis (RR, 5.4; 95% CI, 1.9-15.3, and RR, 3.3; 95% CI, 1.2-9.1, respectively). In conclusion, both HHV-6 reactivation and receipt of BC3 for prophylaxis of acute graft-versus-host disease independently increased the risk of encephalitis in allogeneic BMT recipients. Prospective studies to better define the relationship between HHV-6 reactivation and encephalitis in allogeneic BMT recipients are warranted.

Multidrug-resistance phenotype and clinical responses to gemtuzumab ozogamicin

Expression of multidrug resistance (MDR) features by acute myeloid leukemia (AML) cells predicts a poor response to many treatments. The MDR phenotype often correlates with expression of P-glycoprotein (Pgp), and Pgp antagonists such as cyclosporine (CSA) have been used as chemosensitizing agents in AML. Gemtuzumab ozogamicin, an immunoconjugate of an anti-CD33 antibody linked to calicheamicin, is effective monotherapy for CD33(+) relapsed AML. However, the contribution of Pgp to gemtuzumab ozogamicin resistance is poorly defined. In this study, blast cell samples from relapsed AML patients eligible for gemtuzumab ozogamicin clinical trials were assayed for Pgp surface expression and Pgp function using a dye efflux assay. In most cases, surface expression of Pgp correlated with Pgp function, as indicated by elevated dye efflux that was inhibited by CSA. Among samples from patients who either failed to clear marrow blasts or failed to achieve remission, 72% or 52%, respectively, exhibited CSA-sensitive dye efflux compared with 29% (P =.003) or 24% (P <.001) among samples from responders. In vitro gemtuzumab ozogamicin--induced apoptosis was also evaluated using an annexin V--based assay. Low levels of drug-induced apoptosis were associated with CSA-sensitive dye efflux, whereas higher levels correlated strongly with achievement of remission and marrow blast clearance. In vitro drug-induced apoptosis could be increased by CSA in 14 (29%) of 49 samples exhibiting low apoptosis in the absence of CSA. Together, these findings indicate that Pgp plays a role in clinical resistance to gemtuzumab ozogamicin and suggest that treatment trials combining gemtuzumab ozogamicin with MDR reversal agents are warranted. (Blood. 2001;98:988-994)