European LeukemiaNet-defined primary refractory acute myeloid leukemia: the value of allogeneic hematopoietic stem cell transplant and overall response

We sought to appraise the value of overall response and salvage chemotherapy, inclusive of allogeneic hematopoietic stem cell transplant (AHSCT), in primary refractory acute myeloid leukemia (prAML). For establishing consistency in clinical practice, the 2017 European LeukemiaNet (ELN) defines prAML as failure to attain CR after at least 2 courses of intensive induction chemotherapy. Among 60 consecutive patients (median age 63 years) correspondent with ELN-criteria for prAML, salvage was documented in 48 cases, 30/48 (63%) being administered intensive chemotherapy regimens and 2/48 consolidated with AHSCT as first line salvage. 13/48 (27%) attained response: CR, 7/13 (54%), CRi, 2/13 (15%), MLFS, 4/13 (31%). The CR/CRi rate was 9/48 (19%), with CR rate of 7/48 (15%). On univariate analysis, intermediate-risk karyotype was the only predictor of response (44% vs 17% in unfavorable karyotype; P = 0.04). Administration of any higher-dose (>1 g/m²) cytarabine intensive induction (P = 0.50), intensive salvage chemotherapy (P = 0.72), targeted salvage (FLT3 or IDH inhibitors) (P = 0.42), greater than 1 salvage regimen (P = 0.89), age < 60 years (P = 0.30), and de novo AML (P = 0.10) did not enhance response achievement, nor a survival advantage. AHSCT was performed in 12 patients with (n = 8) or without (n = 4) CR/CRi/MLFS. 1/2/5-year overall survival (OS) rates were 63%/38%/33% in patients who received AHSCT (n = 12) vs 27%/0%/0% in those who achieved CR/CRi/MLFS but were not transplanted (n = 5), vs 14%/0%/0% who were neither transplanted nor achieved CR/CRi/MLFS (n = 43; P < 0.001); the median OS was 18.6, 12.6 and 5.6 months, respectively. Although CR/CRi/MLFS bridged to AHSCT (n = 8), appeared to manifest a longer median OS (20 months), vs (13.4 months) for those with no response consolidated with AHSCT (n = 4), the difference was not significant P = 0.47. We conclude AHSCT as indispensable for securing long-term survival in prAML (p = 0.03 on multivariate analysis), irrespective of response achievement.

Differential expression of interferon-induced genes and other tissue-based biomarkers in acute graft-versus-host disease vs. lupus erythematosus in skin

BACKGROUND

In both acute graft-versus-host disease (GVHD) and lupus erythematosus (LE), the patient's own tissues are subjected to immunological assault via complex mechanisms influenced by interferon (IFN) and other cytokines. Although not typically confused clinically, these entities have overlapping histopathological findings in the skin.

AIM

To assess whether GVHD can be differentiated from LE using molecular methods on skin specimens.

METHODS

We developed a quantitative reverse transcription PCR assay based on previously identified tissue-based biomarkers of cutaneous GVHD, and compared gene expression in GVHD with that in LE.

RESULTS

Both entities showed robust expression of IFN-induced genes and of genes encoding proteins involved in antigen presentation, cell signalling and tissue repair. Levels of gene expression differed significantly in GVHD compared with LE, particularly those of IFN-induced genes such as MX1, OAS3, TAP1 and STAT3 (P < 0.01). Three logistic regression models could differentiate the two entities with a high degree of certainty (receiver operating characteristic area under the curve of 1.0).

CONCLUSION

The study demonstrates the feasibility of distinguishing between microscopically similar inflammatory dermatoses using tissue-based molecular techniques.

A vicious loop of fatty acid-binding protein 4 and DNA methyltransferase 1 promotes acute myeloid leukemia and acts as a therapeutic target

Aberrant DNA methylation mediated by deregulation of DNA methyltransferases (DNMT) is a key hallmark of acute myeloid leukemia (AML), yet efforts to target DNMT deregulation for drug development have lagged. We previously demonstrated that upregulation of fatty acid-binding protein 4 (FABP4) promotes AML aggressiveness through enhanced DNMT1-dependent DNA methylation. Here, we demonstrate that FABP4 upregulation in AML cells occurs through vascular endothelial growth factor (VEGF) signaling, thus elucidating a crucial FABP4-DNMT1 regulatory feedback loop in AML biology. We show that FABP4 dysfunction by its selective inhibitor BMS309403 leads to downregulation of DNMT1, decrease of global DNA methylation and re-expression of p15INK4B tumor suppressor gene by promoter DNA hypomethylation in vitro, ex vivo and in vivo. Functionally, BMS309403 suppresses cell colony formation, induces cell differentiation, and, importantly, impairs leukemic disease progression in mouse models of leukemia. Our findings highlight AML-promoting properties of the FABP4-DNMT1 vicious loop, and identify an attractive class of therapeutic agents with a high potential for clinical use in AML patients. The results will also assist in establishing the FABP4-DNMT1 loop as a target for therapeutic discovery to enhance the index of current epigenetic therapies.

The evolving role of chemotherapy and hematopoietic cell transplants in Ph-positive acute lymphoblastic leukemia in adults

The introduction of the tyrosine kinase inhibitors (TKI) into the treatment of patients with Ph or BCR-ABL1-positive acute lymphoblastic leukemia has revolutionized the treatment of this poor prognosis acute leukemia. The combination of TKI with chemotherapy has improved response rates and allowed more patients to proceed to allogeneic hematopoietic cell transplant (alloHCT). Older patients have excellent responses to TKI and corticosteroids or in combination with minimal chemotherapy. This raises the question as to whether patients require full-intensity chemotherapy with TKI to achieve molecular remissions. The pediatricians have proposed that cure is achievable without alloHCT in children. These results have suggested that many patients may not require traditional chemotherapy in addition to TKI to achieve remission, and that patients who achieve a negative minimal residual disease state may not require alloHCT. The data in support of these questions is presented here and a suggested future clinical trial design based on these data is proposed.

Prognostic relevance of lymphocytopenia, monocytopenia and lymphocyte-to-monocyte ratio in primary myelodysplastic syndromes: a single center experience in 889 patients

Current prognostic models for myelodysplastic syndromes (MDS), including the Revised International Prognostic Scoring System (IPSS-R), do not account for host immunity. We retrospectively examined the prognostic relevance of monocytopenia, lymphocytopenia and lymphocyte-to-monocyte ratio (LMR) in a cohort of 889 patients with primary MDS. After a median follow-up of 27 months, 712 (80%) deaths and 116 (13%) leukemic transformation were documented. In univariate analysis, subnormal absolute lymphocyte count (ALC) <0.9 × 10⁹/l; P=0.001), ALC<1.2 × 10⁹/l (P=0.0002), subnormal absolute monocyte count (AMC) <0.3 × 10⁹/l (P=0.0003), LMR (P⩽0.0001) and LMR⩾5 (P=0.03) were all associated with inferior overall survival. In multivariable analysis that included other risk factors, significance was retained for LMR (P=0.02) and became borderline for ALC <1.2 × 10⁹/l (P=0.06). Analysis in the context of IPSS-R resulted in P-values of 0.06 for ALC<1.2 × 10⁹/l, 0.7 for monocytopenia and 0.2 for LMR. Leukemia-free survival was not affected by ALC, AMC or LMR. The observations from the current study suggest a possible detrimental role for altered host immunity in primary MDS, which might partly explain the therapeutic benefit of immune-directed therapy, including the use of immune modulators; however, IPSS-R-independent prognostic value for either ALC or AMC was limited.

Fatty acid-binding protein FABP4 mechanistically links obesity with aggressive AML by enhancing aberrant DNA methylation in AML cells

Obesity is becoming more prevalent worldwide and is a major risk factor for cancer development. Acute myeloid leukemia (AML), the most common acute leukemia in adults, remains a frequently fatal disease. Here we investigated the molecular mechanisms by which obesity favors AML growth and uncovered the fatty acid-binding protein 4 (FABP4) and DNA methyltransferase 1 (DNMT1) regulatory axis that mediates aggressive AML in obesity. We showed that leukemia burden was much higher in high-fat diet-induced obese mice, which had higher levels of FABP4 and interleukin (IL)-6 in the sera. Upregulation of environmental and cellular FABP4 accelerated AML cell growth in both a cell-autonomous and cell-non-autonomous manner. Genetic disruption of FABP4 in AML cells or in mice blocked cell proliferation in vitro and induced leukemia regression in vivo. Mechanistic investigations showed that FABP4 upregulation increased IL-6 expression and signal transducer and activator of transcription factor 3 phosphorylation leading to DNMT1 overexpression and further silencing of the p15^INK4B tumor-suppressor gene in AML cells. Conversely, FABP4 ablation reduced DNMT1-dependent DNA methylation and restored p15^INK4B expression, thus conferring substantial protection against AML growth. Our findings reveal the FABP4/DNMT1 axis in the control of AML cell fate in obesity and suggest that interference with the FABP4/DNMT1 axis might be a new strategy to treat leukemia.

Voriconazole exposure and the risk of cutaneous squamous cell carcinoma in allogeneic hematopoietic stem cell transplant patients

BACKGROUND

Voriconazole is a commonly used antifungal medication in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients. In solid organ transplantation, voriconazole use has been associated with the development of cutaneous squamous cell carcinoma (SCC). We sought to determine if voriconazole use was associated with SCC in patients undergoing allo-HSCT.

METHODS

We retrospectively reviewed consecutive adult patients who underwent allo-HSCT at Mayo Clinic from January 2007 through July 2012. Multivariable Cox models were created to assess the relationship of SCC with two time-dependent voriconazole exposure variables: (i) history of voriconazole exposure (yes/no), and (ii) cumulative days of voriconazole use.

RESULTS

In our cohort of 381 allo-HSCT patients, SCC developed in 26 of 312 patients exposed to voriconazole (25 post-voriconazole) and in 1 of 69 patients who received alternative antifungal agent(s). Cumulative incidence of SCC was estimated to be 19% at 5 years post allo-transplant. Cumulative days of voriconazole use was found to be a risk factor for SCC, and this relationship persisted in a multivariable model using previously identified risk factors as covariates (hazard ratio 1.859 for each 180 days of use, P < 0.001).

CONCLUSION

This is the first study, to our knowledge, to identify cumulative days of voriconazole use as a risk factor for SCC development following allo-HSCT, and may help guide appropriate antifungal use in this patient population.

Impact of lymphocyte and monocyte recovery on the outcomes of allogeneic hematopoietic SCT with fludarabine and melphalan conditioning

We have recently shown that lymphocyte and monocyte recovery by day +100 are associated with survival post myeloablative allogeneic hematopoietic transplant for acute leukemia. We hypothesized that lymphocyte and monocyte recovery would have a similar impact on survival in the reduced intensity setting. To test this hypothesis, we analyzed clinical data from 118 consecutive fludarabine/melphalan-conditioned patients by correlating peripheral blood absolute lymphocyte counts and monocyte counts (ALC and AMC, respectively) at days +15, +30, +60 and +100 with the outcomes. Multivariate analysis revealed that day +100 AMC (risk ratio (RR) 0.22, 95% confidence interval (CI) 0.07-0.73, P=0.01) and mild chronic GVHD (RR 0.09, 95% CI 0.005-0.43, P=0.008) were independently associated with survival. To explore whether the patterns of lymphocyte and monocyte recovery had a prognostic value, we performed unsupervised hierarchical clustering on the studied hematopoietic parameters and identified three patient clusters, A-C. Patient clusters A and B both had improved OS compared with cluster C (77.8 months vs not reached vs 22.3 months, respectively, P<0.001). No patient in cluster C had a day +100 AMC >300. Both severe acute GVHD and relapse occurred more frequently in cluster C. Our data suggest that patients with low AMC by day +100 post fludarabine/melphalan-conditioned allogeneic hematopoietic SCT may be at risk for poor outcomes.

Low risk of symptomatic venous thromboembolic events during growth factor administration for PBSC mobilization

The use of erythropoietic agents has been associated with an increased risk of venous thromboembolic events (VTEs), especially in patients with underlying malignancies. However, it is not known whether there is an increased risk of VTE associated with granulocyte growth factors. We reviewed 621 patients undergoing PBSC mobilization using granulocyte growth factors, alone or in combination with CY. Patients with a diagnosis of AL amyloidosis (AL: 114; 18%), multiple myeloma (MM: 278; 44%) Hodgkin lymphoma (HL: 20; 3%) or non-Hodgkin lymphoma (NHL: 209; 33%) were included. Symptomatic VTE occurred in six (0.97%) patients: two AL, two MM and two NHL. Of the six patients, two had pulmonary embolism, one developed deep vein thrombosis and three developed symptomatic catheter related thrombosis. Two patients with AL had heparin-induced thrombocytopenia and thrombosis. We found a low incidence of VTE among patients undergoing PBSC mobilization.

JAK2 germline genetic variation affects disease susceptibility in primary myelofibrosis regardless of V617F mutational status: nullizygosity for the JAK2 46/1 haplotype is associated with inferior survival

A common JAK2 germline haplotype (46/1) has been associated with JAK2V617F (VF)-positive myeloproliferative neoplasms. The rs12343867 SNP (C/T) tags this haplotype. A total of 130 patients (77 VF-positive) with primary myelofibrosis (PMF) were analyzed for this informative SNP, using bone marrow-derived DNA. The observed 46/1 C allele frequencies in VF-positive (50%) and VF-negative (36%) patients were both significantly higher than expected in population controls (P<0.01). Genotype distributions in VF-positive/VF-negative patients were CC 31%/9%, CT 38%/53% and TT 31%/38% (P=0.01). CC genotype/C-allele frequencies in patients with <20% VF mutation burden (12%/37%) were similar (P=0.95) to those seen in VF-negative patients (9%/36%), but were significantly lower (P<0.01) than those seen in the presence of >50% mutation burden ( approximately 67%/71%). The rs12343867 genotype did not correlate with the International Prognostic Scoring System (IPSS) score or karyotype. Unexpectedly, the TT genotype was associated with shortened survival (P<0.01), which was not accounted for by IPSS score or VF allele burden. We conclude that JAK2 germline genetic variation affects disease susceptibility, and possibly survival, in PMF, regardless of VF mutational status. Allelic distortion from acquired uniparental disomy contributes to the appearance of a more pronounced effect on disease susceptibility in VF-positive patients, when studying clonally affected tissue.

Kinetics of interferon-gamma producing cytomegalovirus (CMV)-specific CD4+ and CD8+ T lymphocytes and the risk of subsequent CMV viremia after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Deficiencies in cytomegalovirus (CMV)-specific T lymphocytes impair the immunologic response against CMV reactivation after allogeneic hematopoietic stem cell transplantation (HSCT).

METHODS

A time-dependent analysis was conducted to determine the association between the percentages and kinetics of interferon-gamma-producing CMV-specific CD4+ and CD8+ T lymphocytes and CMV viremia among 30 allogeneic HSCT recipients.

RESULTS

Higher percentages of CD4+ T lymphocytes activated with CMVpp65 (hazard ratio [HR]: 2.06; 95% confidence interval [95% CI]: 1.18-3.6; P=0.011) and CMV lysate (HR: 1.18; 95% CI: 0.99-1.42; P=0.072), and higher percentages of CD8+ T lymphocytes activated by CMV immediate early-1 (HR: 1.2; 95% CI: 1.01-1.43; P=0.038) and CMVpp65 (HR: 1.12; 95% CI: 1.0-1.27; P=0.060) were associated with time-to-CMV viremia. Furthermore, a higher degree in the decline of CMV lysate-activated CD4+ T lymphocytes (HR: 1.14; 95% CI: 0.96-1.36; P=0.125) and CMVpp65-activated CD8+ T lymphocytes (HR: 1.36; 95% CI: 1.03-1.78; P=0.031) was suggestive of or significantly associated with time-to-CMV viremia.

CONCLUSIONS

Higher levels of CMV-specific CD4+ and CD8+ T lymphocytes were associated with subsequent CMV viremia after HSCT. The association between CMV viremia and the degree of decline in CMV-specific T lymphocytes suggests that severe disruption in homeostatic CMV-specific immune environment contributes to the immunopathogenesis of CMV after allogeneic HSCT.

A randomized trial of anthracycline dose intensification during induction of younger patients with acute myeloid leukemia: Results of Eastern Cooperative Oncology Group study E1900

7003

Background: In younger adults with newly diagnosed acute myeloid leukemia (AML), anthracycline dose intensification during induction may improve complete remission (CR) rates; however, an improvement in overall survival (OS) in a randomized trial has not been demonstrated. This unresolved issue led the ECOG to compare standard dose (SDD) to high-dose daunorubicin (HDD) in induction. Methods: Adult patients with previously untreated AML were randomized to receive either SDD (45 mg/m2/d) or HDD (90 mg/m2/d) each for 3days combined with standard-dose cytarabine (100 mg/m2/d) for 7 days by continuous intravenous infusion. Those achieving a CR were allocated to allogeneic hematopoietic stem cell transplantation (HSCT) or high-dose cytarabine (with or without a single dose of gemtuzumab ozogamicin) prior to autologous HSCT. Intravenous busulfan and cyclophosphamide was the preparative regimen for both allogeneic and autologous HSCT. The primary end point of this study was OS from the time of induction randomization. Results: 633 patients, age 18 to 60 (median 48) years, were entered in this study. There were no differences in patient demographics or disease characteristics between the two groups at presentation. In an intention-to-treat analysis, HDD resulted in a significantly higher CR rate (63.3% vs. 47.7%, p = 0.0003) than SDD. Induction deaths were similar between the two groups (5.4 vs. 5.0%, p = ns). 334 (52.8%) patients entered the consolidation phase. 57.4% of HDD and 48.1% of the SDD patients, received consolidation therapy on study, and 28.7% and 23.1% proceeded to HSCT respectively. Median OS was superior for the HDD (23.7 months) over the SDD (15.1 months) group (p = 0.005). In subgroup analysis, patients with favorable or intermediate-risk cytogenetics or age <55 years benefited from the HDD. Conclusions: We demonstrate for the first time in a prospective randomized trial that intensifying induction therapy through a higher daily anthracycline dose, in the setting of identical intensive consolidation therapy, results in a higher CR rate as well as prolonged OS. In younger AML patients a higher dose of anthracycline in induction should be considered the new standard of care.

No significant financial relationships to disclose.

Low risk for symptomatic venous thromboembolic events (vte) during cytokine administration for peripheral blood stem cell mobilization

7039

Background: Erythropoiesis-stimulating agents are known to increase the risk for VTE events, especially in patients with underlying malignancies. However, there is a paucity of information on other hematopoietic growth factors such as granulocyte colony-stimulating factor (GSCF) granulocyte-macrophage colony stimulating factor (GM-CSF) AMD 3001 and risk for VTE. Methods: Between January 2000 and October 2008, a total of 631 patients underwent peripheral blood stem cell mobilization (PBSCM) using either GCSF, GMCSF, cyclophosphamide, AMD 3100, or with any of the above combination. We included only patients with a diagnosis of AL amyloidosis (AL), multiple myeloma (MM) Hodgkin's lymphoma (HL) and non Hodgkin's lymphoma (NHL). Patients’ demographic details and diagnosis of VTE were collected from electronic medical records. Results: Of the 631 patients who underwent PBSCM the median age of the patients was 57 years (range 17–77). 448 patients (71%) received single agent GCSF, 82 (13%) received combination of GMCSF and cyclophosphamide, 52 (8%) received cyclophosphamide and GCSF, 30 patients received a combination of GMCSF and GCSF, 10 (1.5%) patients received GCSF and AMD 3100. Of the 631 patients, 278 (44%) MM, 209 (33%) NHL, 114 (18%) AL, and 20 (3%) had HL. We found 7 (1.1%) patients with symptomatic VTE occurring between administration of growth factors and stem cell transplant. The median duration from the administration of growth factors to detection of VTE was 5 days (range 1–30). Two AL,3 MM and 2 NHL. Of the 7 patients, 2 patients had pulmonary embolism and 1 patient developed deep vein thrombosis. Two patients with AL developed heparin induced thrombocytopenia (HIT). The remaining 4 patients developed symptomatic catheter related thrombosis. Only 1 patient had past history of VTE. Of the 7 patients, 5 received GCSF alone, 1 received GMCSF, and cyclophosphamide, 1 received GCSF and cyclophosphamide. Of the 4 patients who developed catheter related thrombosis, catheter was removed in 2 patients. None of the patients developed VTE related morality. Conclusions: The risk for symptomatic VTE during PBSCM is low. HIT should be considered as a possible cause for VTE in patients undergoing PBSCM.

No significant financial relationships to disclose.

Comparison of high-dose CY and growth factor with growth factor alone for mobilization of stem cells for transplantation in patients with multiple myeloma

We retrospectively analyzed outcomes of 716 patients with multiple myeloma who were mobilized using CY and growth factor (n=370) or growth factor alone (n=346) before SCT. Patients receiving CY had higher stem cell yields than the growth factor only group (median number of apheresis sessions needed to achieve stem cell collection goals, two vs four sessions, respectively (P=0.001)). However, patients treated with CY required more time for engraftment of platelets and neutrophils (P<0.001 for both). For patients receiving CY, 75% achieved engraftment (defined as a platelet count of 50 x 10(9)/l) by day 39, whereas 75% of patients not receiving CY achieved engraftment by day 18. Similar results were observed for neutrophil engraftment. These differences did not affect the duration of hospitalization, but patients treated with CY had a higher incidence of post transplant nonstaphylococcal bacteremia. For CY-mobilized patients, considerably faster platelet engraftment (5 fewer days) resulted if stem cell reinfusion occurred more than 30 days after the first apheresis session. Our data suggested that CY damaged the microenvironment and slowed engraftment. By lengthening the period between the completion of apheresis and stem cell reinfusion, the microenvironment may recover and result in faster engraftment.

Impact of lenalidomide therapy on stem cell mobilization and engraftment post-peripheral blood stem cell transplantation in patients with newly diagnosed myeloma

While initial therapies have become highly effective with introduction of lenalidomide and bortezomib and patients may opt for delayed stem cell transplantation, it is important to collect stem cells for future transplant. Given its increasing use as initial therapy, we examined if lenalidomide had any impact on the ability to collect peripheral blood stem cells (PBSC). We studied the entire cohort of patients with myeloma undergoing PBSC mobilization at our institution during a 5-year period, comparing the results between patients receiving different initial therapies. Among those mobilized with granulocyte-colony stimulating factor (G-CSF) alone, there was a significant decrease in total CD34(+) cells collected (P<0.001), average daily collection (P<0.001), day 1 collection (P<0.001) and increased number of aphereses (P=0.004) in patients treated with lenalidomide compared to those receiving dexamethasone, thalidomide-dexamethasone or VAD. A similar trend was seen in those mobilized with chemotherapy and G-CSF. A trend was seen towards decreased PBSC yield with increasing duration of lenalidomide therapy as well as increasing age (P=0.002). There was no effect on quality of PBSC collected based on similar engraftment across all groups. We recommend collection of PBSC within 6 months of initiation of therapy with lenalidomide containing regimens to minimize the risk of mobilization failures.

Outcome after second stem cell transplantation for relapsed multiple myeloma

8118

Background: Autologous stem cell transplantation (ASCT) improves survival and remains the standard of care for patients with newly diagnosed myeloma considered eligible for transplant. However, ASCT is not curative and patients relapse after a median interval of 24–30 months. While new therapeutic options have become available for relapsed MM, repeat ASCT remains an option especially when previously collected stem cells are available. The outcome of pts going to a second SCT in the relapsed setting has not been studied extensively. Methods: We identified pts with myeloma who received a second SCT from a prospectively maintained database. Planned tandem ASCTs were excluded. 56 pts received a second SCT for relapsed MM, including 11 allogeneic SCTs. Among the 45 second ASCTs, 5 were followed by reduced intensity allogeneic SCT and were analyzed with the allogeneic group. Results: The median age at second ASCT was 60.2 yrs (range, 41.3–74.4) and 27 (68%) were males. The median time to second ASCT from diagnosis, first ASCT and relapse were 47.4 mos (22.8–158.6), 36.3 mos (13.5–129.8) and 7.2 mos (1–32) respectively. Among patients receiving second APBSC, 14 (35%) patients were alive with a median follow up of 10.5 mos (1–45 mos). All patients received melphalan conditioning. The median time to neutrophil engraftment was 15 days and platelet engraftment was 16 days. The median hospitalization was 4 days (range 0–33) and there was one transplant related death in the group. The best response included 13 pts with CR (33%), 4 with VGPR (10%), and 19 with PR (48%). MM has relapsed in 22 (55%) pts with a median PFS of 12.5 mos from second ASCT. The median estimated OS from diagnosis, first ASCT and second ASCT were 100.5 mos, 65.9 mos, and 30.6 mos respectively. Among the 16 pts receiving allogeneic SCT, 8 pts (50%) were alive at analysis with a median PFS and OS from transplant of 17.9 mos and 33.5 mos respectively. Conclusions: Second ASCT as salvage therapy for relapsed MM is a viable approach and has a favorable outcome in this selected group of patients. The toxicity, engraftment kinetics, hospitalization and the response rates are comparable to patients undergoing initial ASCT. Allogeneic SCT with or with out a preceding ASCT results in comparable survival in selected patients with high risk disease.

No significant financial relationships to disclose.

Outcome of patients relapsing early after autologous stem cell transplantation for multiple myeloma

8022

Background: Autologous stem cell transplant (ASCT) is the standard approach for eligible patients (pts) with multiple myeloma (MM). The median time to relapse after early ASCT is 2–3 yrs and overall survival (OS) is 4–5 yrs. Though various risk factors have been identified for early relapse, the outcome of this group of pts is not clearly described. With the advent of newer therapies, it is important to understand the natural history of MM in these pts to design treatment strategies. Methods: A total of 432 pts with MM, undergoing ASCT within 12 months (mos) of diagnosis, with a minimum follow up of 12 mos were studied. Clinical and laboratory data were obtained from a prospectively maintained database and clinical records. Pts were divided into 2 groups: early relapse (relapse <12 mos from ASCT) and late relapse (either relapsed >12 mos after ASCT or disease free at last follow up). Results: There were 94 pts (22%) in the early relapse group and among the late relapse group (N=338), 171 had relapsed beyond 12 mos and 167 were disease free at last follow up. The median time to ASCT was similar in all groups. The early relapse group had a significantly shorter median OS from diagnosis (23.9 vs. 82.2 months; P < 0.001) and from transplant (17.6 mos vs. not reached; P < 0.001). The median OS from relapse was 7.9 mos in this group compared to 39.6 months for the rest. In univariate analysis, elevated CRP, high BM plasma cell%, labeling index (PCLI) >1%, abnormal cytogenetics, presence of circulating PCs at harvest and lack of CR from ASCT predicted for early relapse. In multivariate analysis, an elevated PCLI (RR=2.9; P=0.002) and failure to achieve CR (RR 2.7; P=0.002) was associated with early relapse. Conclusions: Pts who relapse within 12 mos of an ASCT have a very short survival and should be offered trials evaluating novel therapies and combinations. Survival figures from this study represent the benchmark for the comparison of novel approaches in this population. Pts with poor prognostic factors have a short PFS after ASCT and should be considered for alternative approaches. Inability to achieve CR appears to predict shorter PFS and clinical trials evaluating maintenance therapy should be offered in these pts.

No significant financial relationships to disclose.

Trisomy 13 in patients with hematological malignancies

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Introduction: Cytogenetic abnormalities have been shown to be the most important determinant of prognosis in patients with acute myeloid leukemia (AML). In AML, trisomy 13 has been placed in the intermediate prognostic category although recent reports associate it with a more dismal outcome. The number of cases reported in the literature are relatively few, we reviewed our experience with trisomy 13 in hematologic malignancies to determine its significance and prognosis. Methods: We conducted a clinicopathological review of cases seen in our institution from January of 1990 to October of 2006. Our cytogenetic records were searched for patients, who had a hematological disorder whose non-stimulated bone marrow karyotype was found to have trisomy 13 as a sole abnormality. In men the absence of the Y chromosome was not regarded as a separate abnormality. Results: A total of 27 patients were identified. The median age was 76 years (range 25–87), 22/27 were male. The number of cases and diseases identified were 15 with AML, 5 with a myelodysplastic syndrome, 4 with an uncategorized myelodysplastic/myeloproliferative disorder, 2 with acute lymphoblastic leukemia and 1 with a chronic myeloproliferative disorder. Of the AML group 7 were M0 according to the FAB classification, 2 patients were identified to have M4 and another two M2. A single case each of M1 and M6 was also identified. In these 15 patients, 9 underwent induction chemotherapy, which consisted of intermediate dose Ara-C in 3 cases, anthracycline plus Ara-C in 5 patients, and daunorubicin, vincristine and prednisone in 1. Another 3 patients were given palliative treatment. For the rest of the subjects the type of treatment was unknown. A CR was obtained in 6 patients, 1 patient underwent a myeloablative stem cell transplant. Death has occurred in 24 patients, the median survival of the entire group was 5.4 months. In the patients with AML the median survival was 4.7 months, of the patients who achieved a CR the median survival was 9.5 months. Conclusions: We describe one of the largest series reported to date of trisomy 13 in hematologic malignancies and found that trisomy 13 is associated with male gender and an older age at presentation, as well as a poor prognosis. In AML its presence is associated with an FAB-M0 phenotype and its occurrence should be regarded as a high-risk feature.

No significant financial relationships to disclose.

Prognostic value of chromosome 1q21 gain by fluorescent in situ hybridization and increase CKS1B expression in myeloma

A specific role for increased level of expression of CKS1B, as a consequence of chromosome 1q21 copy number gain, has been postulated as both pathogenic, as well as a powerful clinical prognostic factor in multiple myeloma (MM). The purpose of this study is to determine the clinical associations and prognostic impact of copy number gain at chromosome 1q21 (with a bacteria artificial chromosome clone containing CKS1B) and CKS1B gene level of expression in MM. We studied the chromosome region 1q21 for copy number change in a cohort of myeloma patients treated by high-dose therapy with stem-cell rescue (HDT) (n = 159). A separate cohort of patients, treated by HDT was studied for CKS1B messenger RNA expression by gene expression profiling (n = 67). 1q21 gain was then correlated with clinical parameters and survival. Gain of 1q21 copy number was detected in about a third of MM and was associated with more proliferative disease and poor-risk cytogenetic categories such as t(4;14), and chromosome 13 deletion. Both 1q21 gain and increase gene expression level were significantly associated with reduced survival. However, neither is an independent prognostic marker in MM on multivariate Cox proportional hazard analysis.

Absolute lymphocyte count recovery after induction chemotherapy predicts superior survival in acute myelogenous leukemia

Absolute lymphocyte count (ALC) recovery postautologous stem cell transplantation is an independent predictor for survival in acute myelogenous leukemia (AML). The role of ALC recovery after induction chemotherapy (IC) in AML is unknown. We hypothesize that ALC recovery after IC has a direct impact on survival. We have now evaluated the impact of ALC recovery after IC on overall survival (OS) and leukemia-free survival (LFS) in 103 consecutive, newly diagnosed AML patients treated with standard IC and consolidation chemotherapy (CC) from 1998 to 2002. ALC recovery was studied at days 15 (ALC-15), 21 (ALC-21), 28 (ALC-28) after IC and before the first CC (ALC-CC). Superior OS and LFS at each time point were observed with an ALC-15, ALC-21, ALC-28, and ALC-CC > or = 500 cells/microl. Patients with an ALC > or = 500 cells/microl at all time points vs those who did not have superior OS and LFS (not reached vs 13 months, P<0.0001; and not reached vs 11 months, P<0.0001, respectively). Multivariate analysis demonstrated ALC > or = 500 cells/microl at all time points to be an independent prognostic factor for survival. Our data suggest a critical role of lymphocyte (immune) recovery on survival after IC in AML.

Autologous hematopoietic stem cell transplantation for older patients with relapsed non-Hodgkin's lymphoma

To evaluate autologous stem cell transplant (ASCT) in older patients with intermediate grade non-Hodgkin's lymphoma (NHL), the Mayo Clinic Rochester BMT database was reviewed for all patients 60 years of age and older who received ASCT for NHL between September 1995 and February 2003. Factors evaluated included treatment-related mortality (TRM), event-free survival (EFS) and overall survival (OS). Ninety-three patients were identified, including twenty-four (26%) over the age of 70 years. Treatment-related mortality (5.4%) was not significantly different when compared to a younger cohort (2.2%). At a median follow-up of 14 months (0.6-87.6 months), the estimated median survival is 25 months (95% confidence interval (CI) 12-38) in the older group compared to 56 months (95% CI 37-75) (P=0.037) in the younger group. The estimated 4-year EFS was 38% for the older group compared to 42% in the younger cohort (P=0.1). By multivariate analysis, the only factor found to influence survival in the older group was age-adjusted International Prognostic Index at relapse, 0-1 better than 2-3 (P=0.03). Autologous stem-cell transplant can be safely performed in patients 60 years or older with chemotherapy sensitive relapsed or first partial remission NHL. The outcome may not be different from that of younger patients in terms of TRM and EFS.

Prediction of survival using absolute lymphocyte count for newly diagnosed patients with multiple myeloma

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Background: In the setting of autologous stem cell transplantation (ASCT) in multiple myeloma (MM), it has been shown that peripheral blood absolute lymphocyte count (ALC) on day 15 is an independent prognostic factor for clinical outcomes. Recently the International Staging System (ISS) for MM has been developed as a simple staging system to assess survival in newly diagnosed MM patients. The role of ALC on survival in newly diagnosed MM patients is unknown. Methods: Between 1994 and 2002, 1,835 consecutive MM patients were evaluated at the Mayo Clinic, Rochester. Of these patients, we retrospectively analyzed 584 MM patients that were originally diagnosed and followed at the Mayo Clinic. The primary end point was to assess the role of ALC at the time of MM diagnosis on overall survival (OS). OS was measured from the date of diagnosis to time of death or last follow-up. ALC was analyzed as a continuous variable and dichotomized based on finding the optimal cut point based on the log-rank statistic. ALC was then compared to the ISS. Results: The median age of the cohort was 67 years (range: 29–94 years), including 234 females and 350 males. The median follow-up was 32 months (range: 1–136 months). The median ALC at diagnosis was 1.2 x 109/L (range: 0.12–5.44 x 109/L). ALC, as a continuos variables was identified as a prognostic factor for OS (HR= 0.466, 95%CI= 0.396–0.547, p < 0.0001). MM patients with an ALC ≥ 1.3 x 109/L experienced a superior OS compared with MM patients with an ALC < 1.3 x 109/L (55.5 months versus 22.6 months, p< 0.0001). In the multivariate analysis, ALC was independent prognostic factor when compared to the ISS (HR = 0.580, 95%CI=0.518–0.647, p< 0.0001). Conclusions: Our study shows that ALC at diagnosis for MM is an independent prognostic factor for OS, suggesting how the host immune status plays a critical role in the survival of patients with MM.

No significant financial relationships to disclose.

Allogeneic stem cell transplantation and donor lymphocyte infusions for chronic myelomonocytic leukemia

Prognosis in chronic myelomonocytic leukemia (CMML) is unfavorable and the optimal therapy remains uncertain. Currently, allogeneic stem cell transplantation is the only known curative therapeutic option. However, the data available are limited and restricted to small retrospective series. There is even less information on the use of donor lymphocyte infusions (DLI) for this disease. We reviewed our experience of allogeneic stem cell transplantation and DLI for adults with CMML. Seventeen consecutive adults underwent allogeneic stem cell transplantation from related (n=14) or unrelated (n=3) donors. Median age was 50 years (range 26-60). Seven patients (41%) demonstrated relapse or persistent disease at a median of 6 months (range 3-55.5). Five patients underwent DLI for morphologic relapse and one for mixed donor chimerism. Two patients achieved durable complete remissions of 15 months each. The overall transplant-related mortality was 41% (n=7). With a median follow-up of 34.5 months, three patients (18%) currently remain alive and in continuous CR. The current study demonstrates a graft-versus-leukemia effect in CMML, both for allogeneic stem cell transplantation and for DLI. Nevertheless, consistent with reported experience of others, overall outcomes remain less than optimal and unpredictable.

Testing the safety of clinical-grade mature autologous myeloid DC in a phase I clinical immunotherapy trial of CML

BACKGROUND

We conducted a phase I clinical immunotherapy trial of CML to evaluate the safety of a clinical-grade leukemic DC product standardized for purity and mature phenotype.

METHODS

We injected autologous DC into patients in late chronic or accelerated phases of CML. The patients received mature CD83+ and bcr-abl+ DC prepared from CD14+ cells. Two cohorts of three patients received four injections each of 3 x 10(6) DC and 15 x 10(6) DC/injection, respectively. The first patient was studied before imatinib mesylate (IM) was available, four patients were treated concurrently with IM therapy and one did not tolerate the IM and was off the drug at the time of DC therapy. IM effects on WBC counts precluded DC preparation in numbers sufficient for further dose escalation. The first patient received DC s.c. and all subsequent patients received DC into a cervical lymph node under ultrasound guidance.

RESULTS

DC injections were well tolerated. We observed no clinical responses. T cells drawn later in the course of therapy were more sensitive to stimulation by CML DC in vitro.

DISCUSSION

The increase in T-cell sensitivity to CML-specific stimulation that accompanied active immunization by CML DC justifies further clinical studies, possibly with modifications such as an increased frequency and number of DC injections.

Emergence of quinolone resistance among viridans group streptococci isolated from the oropharynx of neutropenic peripheral blood stem cell transplant patients receiving quinolone antimicrobial prophylaxis

In neutropenic patients receiving quinolone prophylaxis, bacteremia with viridans group streptococci resistant to quinolones is a known complication. The frequency of occurrence of quinolone-resistant organisms colonizing the oropharynx during antibacterial prophylaxis with a quinolone is not well defined. In 48 patients undergoing hematopoietic stem cell transplantation, the prevalence of quinolone resistance in viridans group streptococci colonizing the oropharynx before and during antibacterial prophylaxis with gatifloxacin or moxifloxacin (most with concomitant penicillin) was determined. For quinolone-resistant isolates, mutations in the genes gyrA and parC, which confer resistance to quinolones, were analyzed. Seventy-four isolates before and 27 isolates during quinolone use were recovered from patients' oropharynxes. The numbers of susceptible isolates recovered before versus during quinolone use were as follows: 52 (70%) versus three (11%) for ciprofloxacin, 66 (89%) versus eight (30%) for levofloxacin, 66 (89%) versus ten (37%) for gatifloxacin, and 67 (91%) versus 11 (41%) for moxifloxacin (p<0.0001). Mutations in gyrA and/or parC were detected in quinolone-resistant isolates. Quinolone-resistant viridans group streptococci are frequently found in the oropharynx of neutropenic patients after a brief (median, 8 days) exposure to gatifloxacin or moxifloxacin.

Risk-adjusted manipulation of melphalan dose before stem cell transplantation in patients with amyloidosis is associated with a lower response rate

High-dose chemotherapy and autologous stem cell transplantation are used increasingly to treat patients with light-chain-related amyloidosis (AL). Treatment-related mortality is approximately 15%. To enable more patients to undergo stem cell transplantation, a risk-adapted strategy has been developed to treat with lower chemotherapy doses those patients who are at excessive risk. It is unclear whether reducing the chemotherapy dose in patients at excessive risk of treatment toxicity reduces the overall response. We retrospectively reviewed 171 AL patients who underwent conditioning chemotherapy with stem cell transplantation. The patients comprised two groups: those receiving standard high-dose melphalan and those receiving intermediate-dose melphalan. Responses were categorized as hematologic response, which used criteria for myeloma response. The two groups showed statistically significant differences; the overall response rates were 75% in the high-dose group and 53% in the intermediate-dose group although treatment-related mortality was the same in both groups. Reducing the melphalan dose appeared to render more AL patients eligible for stem cell transplantation but sacrificed an element of response. Methods are needed to reduce treatment-related toxicity so that more patients can receive full-dose conditioning chemotherapy.

Single agent dexamethasone for pre-stem cell transplant induction therapy for multiple myeloma

Given the survival advantage, high-dose therapy (HDT) remains the standard of care for patients with multiple myeloma eligible for the procedure. For those undergoing HDT, initial therapy aimed at reducing tumor burden is given prior to stem cell harvest. Various regimens, mostly variations of VAD (vincristine, doxorubicin, dexamethasone), are used for induction therapy. We retrospectively evaluated if single agent dexamethasone would be an effective induction therapy, given that it is the most active drug in these combinations. A total of 35 patients who received induction therapy with dexamethasone alone were compared to a similar group of 72 patients who received VAD as the initial therapy. We found a 63% response rate with dexamethasone compared to 74% with VAD (P=0.25). Including minimal responses, the overall response rate for Dex and VAD was 74 and 86%, respectively (P=0.13). The overall and complete response rates to transplant, respectively, were 97 and 26% for the dexamethasone group and 100 and 39% for the VAD group; P=0.33 and 0.18. No significant differences were observed in the progression-free and overall survival at 1 year post transplant. Single agent dexamethasone appears to be an effective alternative to VAD for induction therapy prior to HDT in myeloma.

High-dose therapy and autologous stem cell transplantation for multiple myeloma poorly responsive to initial therapy

Autologous stem cell transplant (SCT) improves survival in multiple myeloma (MM) and remains the standard of care for eligible patients. Nearly a third of patients with newly diagnosed MM fail initial therapy aimed at reducing tumor burden preceding SCT (primary refractory). It is unclear if an initial response is important for successful SCT. We evaluated our experience with SCT in 50 patients with primary refractory MM and compared it to 101 patients with chemosensitive disease receiving SCT. The study cohort had a median age of 56 years (range 29-72) consisting of 87 males (58%). A total of 46 patients (92%) in the refractory group and 100 (99%) in the chemosensitive group had a response to transplant (50% or greater reduction in the M-protein). In all, 10 refractory patients (20%) and 35 (35%) in the chemosensitive group achieved a CR (P=0.06). The 1-year estimated progression-free survival from the time of transplant for the refractory group was 70% compared to 83% for the chemosensitive group (P=0.65). The lack of response to initial induction therapy does not appear to preclude a good response to SCT. We recommend that patients with primary refractory MM be offered early SCT.

A phase I study of 153Sm-EDTMP with fixed high-dose melphalan as a peripheral blood stem cell conditioning regimen in patients with multiple myeloma

Despite response rates of 30% after high-dose chemotherapy with autologous hematopoietic stem cell transplant, patients with multiple myeloma are not cured. 153Samarium ethylenediaminetetramethylenephosphonate (153Sm-EDTMP; Quadramet) is a short-range, beta-emitting therapeutic radiopharmaceutical with avid skeletal uptake. In total, 12 patients were treated with escalating doses of 153Sm-EDTMP (N=3/group; 6, 12, 19.8, and 30 mCi/kg) and a fixed dose of melphalan (200 mg/m(2)). No dose limiting toxicity was seen. To better standardize the marrow compartment radiation dose, the study was modified such that an additional six patients were treated at a targeted absorbed radiation dose to the red marrow of 40 Gy based on a trace labeled infusion 1 week prior to the therapy. Despite rapid elimination of unbound radiopharmaceutical via kidneys and bladder, no episodes of nephrotoxicity, hemorrhagic cystitis, or delayed radiation nephritis were observed with a median follow-up of 31 months (range 8.5-44). Median times to ANC>0.5 and platelet >20 x 10(6)/l were 12 and 11 days, respectively, with no graft failures. Overall response rate was 94% including seven very good partial responses and five complete responses. Addition of 153Sm EDTMP to melphalan conditioning appears to be safe, well-tolerated and worthy of further study.

Infused peripheral blood autograft absolute lymphocyte count correlates with day 15 absolute lymphocyte count and clinical outcome after autologous peripheral hematopoietic stem cell transplantation in non-Hodgkin's lymphoma

Absolute lymphocyte count at day 15 (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) is an independent prognostic factor for survival in non-Hodgkin's lymphoma (NHL). Factors affecting ALC-15 remain unknown. We hypothesized that dose of infused autograft lymphocytes (A-ALC) directly impacts upon ALC-15. A total of 190 consecutive NHL patients received A-ALC between 1993 and 2001. The primary end point was correlation between A-ALC and ALC-15. A strong correlation was identified (r=0.71). A higher A-ALC was infused into patients achieving an ALC-15 > or =500/microl vs ALC-15 <500/microl (median of 0.68 x 10(9)/kg (0.04-2.21 x 10(9)/kg), vs 0.34 x 10(9)/kg (0.04-1.42 x 10(9)/kg), P<0.0001). The median follow-up for all patients was 36 months (maximum of 109 months). The A-ALC threshold was determined at 0.5 x 10(9)/kg. The median overall survival (OS) and progression-free survival (PFS) times were longer in patients who received an A-ALC >/=0.5 x 10(9)/kg vs A-ALC <0.5 x 10(9)/kg (76 vs 17 months, P<0.0001; 49 vs 10 months, P<0.0001, respectively). Multivariate analysis demonstrated A-ALC to be an independent prognostic indicator for OS and PFS. These data support our hypothesis that ALC-15 and survival are dependent upon the dose of infused A-ALC in NHL.

Second transplant for acute and chronic leukemia relapsing after first HLA-identical sibling transplant

Treatment options for persons with leukemia relapsing after allogeneic transplantation are limited. We analyzed the outcome of 279 patients with acute and chronic leukemia, who relapsed after HLA-identical sibling transplantation and received a second allogeneic transplant. The influence of potential risk factors on treatment-related mortality (TRM), relapse, treatment failure (relapse or death) and overall survival after second transplantation were assessed using proportional-hazards regression. The cumulative incidences (95% confidence interval) of relapse and TRM at 5 years were 42 (36-48)% and 30 (24-36)%, respectively. The 5-year probabilities of both overall and leukemia-free survival were 28 (23-34)%. In multivariate analyses, risks of treatment failure and mortality were lower in younger patients (< or =20 years) and patients who relapsed after 6 months from first transplantation. Risks of relapse were lower in patients who relapsed after 6 months from first transplantation and in complete remission prior to second transplantation. Risks of relapse were higher after reduced-intensity conditioning regimens. Any potential advantage of using a different matched related donor for a second transplantation is not supported by these data. Although age, disease status and conditioning regimen are important, duration of remission after first transplantation appear to be the most important determinant of outcome.

The dose of infused lymphocytes in the autograft directly correlates with clinical outcome after autologous peripheral blood hematopoietic stem cell transplantation in multiple myeloma

Absolute lymphocyte count at day 15 (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) is an independent prognostic factor for survival in multiple myeloma (MM); however, factors affecting ALC-15 in MM remain unknown. We hypothesized that the dose of infused peripheral blood autograft lymphocytes (autograft absolute lymphocyte count: A-ALC) impacts ALC-15 recovery. Between 1989 and 2001, 267 consecutive MM patients underwent APHSCT. We set out to determine the correlation between A-ALC and ALC-15 and the utility of A-ALC as a marker for ALC-15 recovery. A-ALC was found to be both a strong predictor for area under curve (AUC=0.93; P=0.0001) and strongly correlated with (r(s)=0.83; P=0.0001) ALC-15 recovery. Higher infused A-ALC was significantly correlated with an ALC-15>/=500/microl. In addition, median post-transplant overall survival (OS) and time to progression (TTP) were longer in patients who received an A-ALC>/=0.5 x 10(9) lymphocytes/kg versus A-ALC <0.5 x 10(9) lymphocytes/kg (58 vs 30 months, P=0.00022; 22 vs 15 months, P<0.00012, respectively). Multivariate analysis demonstrated A-ALC as an independent prognostic indicator for OS and TTP. These results indicate that an infused dose of autograft lymphocytes significantly impacts clinical outcome post-APHSCT in MM.

Effect of allogeneic stem cell transplantation on bone marrow angiogenesis in chronic myelogenous leukemia

Increased bone marrow angiogenesis is a poor prognostic marker in patients with chronic myelogenous leukemia (CML). Allogeneic stem cell transplantation (ASCT) can be curative for patients with CML. Studies in myeloma have shown persistent increased bone marrow microvessel density (MVD) after autologous transplantation. It is not clear if abnormal bone marrow angiogenesis persists following a curative intervention like allogeneic transplantation. We evaluated MVD from bone marrow samples obtained just prior to and at 3-5 months after ASCT in 24 patients with CML. The median MVD pre-transplant was 14 (4-37), with 11 patients having high-grade angiogenesis and 13 having low grade. The median post transplant MVD was 20 (range 5-36), with 12 patients having high-grade angiogenesis and 12 low grade. The median time between biopsies was 4 months (range 1-6 months). The microvessels in the post transplant bone marrow appeared morphologically different with striking dilatation and sinusoidal appearance compared to the pre-transplant marrow. However, there was no significant change in MVD following transplant (P=0.8, paired t-test). Abnormal bone marrow angiogenesis appears to persist in the bone marrow following ASCT for CML, at least in the short term.

Effect of thalidomide on stem cell collection and engraftment in patients with multiple myeloma

The purpose of this study was to determine the effect of thalidomide on stem cell collection and engraftment in patients with multiple myeloma. We performed a retrospective review of 67 patients newly diagnosed with multiple myeloma at Mayo Clinic and treated with a single regimen prior to stem cell transplantation between January of 2000 and September of 2001. Stem cells were collected from 24 patients who received thalidomide, 200 mg/day, with dexamethasone as initial therapy before stem cell collection. These patients were compared with 43 control patients seen during the same period who had received only one previous regimen before stem cell collection and transplantation. The cumulative thalidomide dose before stem cell collection was 17 000 mg over a median of four cycles (range, 2-7 cycles). The thalidomide and control groups were not significantly different in their baseline characteristics, number of stem cells collected, time to collection, or time to engraftment of neutrophils or platelet count of 50 000/microl. Time to platelet count of 20 000/microl was delayed by a median of 4 days (P=0.008), but platelet transfusion requirements did not differ (P=0.95). We concluded that thalidomide does not substantially affect peripheral cell mobilization or engraftment.

Lymphocyte recovery after allogeneic bone marrow transplantation predicts risk of relapse in acute lymphoblastic leukemia

Allogeneic blood and marrow transplantation (BMT) is curative for many patients with high-risk and relapsed acute lymphoblastic leukemia (ALL). However, relapse is an important cause of post-transplantation failure, and there are no reliable markers to predict relapse. A retrospective review of patients with ALL who underwent matched related allogeneic BMT was carried out to examine whether the rate of lymphocyte recovery after transplantation had any prognostic value in ALL. The absolute lymphocyte count (ALC) at days 21 and 30 after transplantation was obtained for 43 patients who received transplants during an 18-year period. Patients with an ALC of 175 x 10(6)/l or less on day 21 were more likely to relapse than those with ALC greater than 175 x 10(6)/l (relative risk, 4; 95% confidence interval, 1.5-11.2). Patients with slower lymphocyte recovery had significantly lower relapse-free survival than those with faster recovery (P=0.0028). There was also a trend toward poorer overall survival among those with a slow lymphocyte recovery (log-rank test; P=0.028). The rate of lymphocyte recovery is prognostic in patients with ALL undergoing allogeneic BMT, and this should be integrated with other predictors to identify patients at high risk of relapse. Such patients could be considered for interventions aimed at prevention of relapse, including rapid withdrawal of immunosuppressive medication or donor lymphocyte infusion.

Secondary myelodysplastic syndrome and acute myelogenous leukemia are significant complications following autologous stem cell transplantation for lymphoma

Secondary myelodysplastic syndrome (sMDS) and acute myelogenous leukemia (AML) have been recognized with increasing frequency following autologous stem cell transplantation (ASCT). A retrospective analysis of 230 consecutive patients with Hodgkin's lymphoma (HL, 64) and non-Hodgkin's lymphoma (NHL, 166) who underwent ASCT was conducted to assess the incidence and risk factors for the development of sMDS/AML. At a median follow up of 41 months (range 0.1-177 months), 10 of 230 patients (4.3%) developed sMDS/AML. The 5-year-actuarial incidence of sMDS/AML was 13.1% and 5-year cumulative incidence by competing risk analysis was 4.2%. The median time to development of sMDS/AML was 39.9 months from the time of ASCT (range 12.1-62.0 months). Complex karyotypes at diagnosis of sMDS/AML included structural anomalies and/or loss of chromosome 5 (eight patients), 7 (five patients), 17 (two patients) and 20 (two patients). All patients subsequently died, at a median of 6.8 months (range 0-39.9) from diagnosis of sMDS/AML. Fluorescent in situ hybridization (FISH) analysis for -5/5q- and -7/7q- were normal in all six patients whose pre-ASCT bone marrow was available for testing. Five of the six had samples available for testing at diagnosis of sMDS/AML and all had abnormal FISH results. By univariate statistical analysis, male gender (P=0.01), prior alkylating agents (mechlorethamine for HL, P=0.001 and cyclophosphamide for NHL, P=0.05) and the number of prior treatment regimens (P=0.04) were significantly associated with the development of sMDS/AML. Given the relatively low incidence rate of sMDS/AML, these analyses are primarily exploratory in nature but provide some insight into relevant risk factors and illustrate the risk of developing sMDS/AML after myeloablative conditioning and ASCT for lymphoma.