News in therapeutic management of chronic lymphoid leukemia

Chronic lymphocytic leukemia follows an extremely variable clinical course with survival range from months to decades. Some patients present minimal symptoms and others organomegaly requiring rapidly therapy. Therapeutic options take into account efficacy, toxicity and prognostic factors. One of the well known prognosis factor is the clinical staging developed either by Rai et al. or by Binet et al. However, there is an important heterogeneity concerning the course of the disease among patients within a single stage group. Recently, several important observations related to the biologic significance of VH gene mutational status, expression of CD38, over-expression of ZAP-70 and chromosomal aberrations have led to the ability to identify high risk patients with rapid disease progression and lower survival. It has been demonstrated that the VH mutation status is clinically highly relevant. CLL patients with unmutated VH gene show an unfavourable course with a very rapid progression. Specific genomic aberrations have been associated with disease characteristics such as lymphadenopathy related to 11q deletion and resistance to treatment related to 17p deletion. VH gene mutation status and genomic aberrations appear separate parameters when considering their prognostic relevance but nevertheless they are correlated: unfavourable aberrations (11q- and 17p-) occur more frequently in VH unmutated CLL patients. According to these prognostic factors, several treatments including purine analogues and/or monoclonal antibodies have been tested with different schedules and doses of monoclonal antibodies (rituximab and alemtuzumab) considering safety to determine the better efficacy. Infections and haemolytic anemia remain the most frequent complications during conventional chemotherapy. In autologous transplant setting, the transplant related mortality is less than 10%, but survival curve do not show a plateau with about 50% of patients relapsing at 4 years. Conventional allogeneic transplantation could achieve durable remission and probably cure the disease but at the price of a too high transplant related mortality related to depressive immune status and old age of CLL population. In order to minimize the toxicity and to improve graft-versus-leukemia effect, development of reduced intensity conditioning (RIC) regimens appear particularly important for CLL patients. Recent studies, although a still short follow-up show very promising results and use of monoclonal antibodies in the conditioning or just after transplant could improve the results of allogeneic stem cell transplantation and cure a larger number of CLL patients. Recent advances to categorize CLL patients according to risk stratification regarding new prognostic factors (FISH, CD38, ZAP70, Ig mutational status) should allow to define better the best therapeutic strategy. In parallel, age, co morbidities and the notion of the risk-adapted strategy have also an important impact adding.     

Myeloablative versus reduced intensity allogeneic stem cell transplantation for relapsed/refractory Hodgkin's lymphoma in recent years: a retrospective analysis of the Lymphoma Working Party of the European Group for Blood and Marrow Transplantation

This registry-based analysis highlights the significant reduction of non-relapse mortality associated to myeloablative allogeneic stem cell transplantation for relapsed/refractory Hodgkin's lymphoma in recent years. Intensity of the conditioning regimen should be taken into consideration when designing prospective clinical trials in this setting.BackgroundTo evaluate long-term outcome of myeloablative allogeneic stem cell transplantation (allo-SCT) (MAC) versus reduced-intensity allo-SCT (RIC) in patients with relapsed/refractory Hodgkin's lymphoma (HL) in recent years.Patients and methodsA total of 312 patients (63 MAC and 249 RIC) with relapsed/refractory HL who received allo-SCT between 2006 and 2010 and were reported to the EBMT Database were included in the study.ResultsWith a median follow-up for alive patients of 56 (26–73) months, there were no significant differences in non-relapse mortality (NRM) between MAC and RIC. Relapse rate (RR) was somewhat lower in the MAC group (41% versus 52% at 24 months, P= 0.16). This lower RR translated into a marginal improvement in event-free survival (EFS) for the MAC group (48% versus 36% at 24 months, P= 0.09) with no significant differences in overall survival (73% for MAC and 62% for RIC at 24 months, P= 0.13). Multivariate analysis after adjusting for disease status at the time of allo-SCT showed that the use of MAC was of borderline statistical significance for predicting a lower RR and EFS [HR 0.7, 95% CI (0.5–1.0), P= 0.1] and [HR 0.7, 95% CI (0.5–1.0), P= 0.07], respectively, after allo-SCT.ConclusionsWith modern transplant practices, the NRM associated with MAC for HL has strongly decreased, resulting into non-significant improvement of EFS because of a somewhat better disease control compared with RIC transplants. The intensity of conditioning regimens should be considered when designing individual allo-SCT strategies or clinical trials in patients with relapsed/refractory HL.     

Chronic lymphocytic leukemia with 6q- shows distinct hematological features and intermediate prognosis.

Cytogenetic and fluorescence in situ hybridization studies were successfully performed in 217 chronic lymphocytic leukemia (CLL). In all, 13 patients with 6q21 deletion were identified and characterized in comparison with 92 patients with 'favourable' karyotype (normal or 13q-), 69 cases with 'intermediate risk' (1-2 anomalies) and 43 cases with 'unfavourable' karyotype (complex, 11q- or 17p-). Six out of 13 cases with 6q- showed an excess of atypical lymphocytes, a finding confirmed at the histologic level; >20% CD38+ cells were seen in 5/6 cases. IGVH mutational status revealed >98% homology to the germline sequence in 4/10 cases. When compared with the 'favourable' group, patients with 6q- showed a higher white blood cell (WBC) count, frequent splenomegaly, atypical morphology, CD38+ and short time from diagnosis to first treatment and short survival. A higher median WBC count was found in the 6q- group vs the intermediate-risk group; survival was shorter in the unfavourable group. To ascertain if the 6q- anomaly was an independent factor predicting for an inferior outcome among those patients with 'favourable' cytogenetics, we performed an analysis of prognostic factors in 105 patients (92 'favourable' plus 13 with 6q-), showing that the 6q- chromosome maintained its prognostic significance at multivariate analysis (P=0.02) along with stage (P=0.01). We conclude that CLL with 6q- is characterized by a high incidence of atypical morphology, classical immunophenotype with CD38 positivity and intermediate incidence of IGVH somatic hypermutation. Clinicobiological features and outcome show that this cytogenetic subset of CLL should be allocated in an intermediate-risk category.     

Increased expression of angiopoietin-2 characterizes early B-cell chronic lymphocytic leukemia with poor prognosis

We measured the angiopoietin-2 (Ang-2) expression in early chronic lymphocytic leukemia (CLL) patients, pointing our attention on the association with immunoglobulin (IgV(H)) mutational status, CD38 expression and clinical outcome. Our results indicate that Ang-2 expression is heterogeneous among Binet stage A CLL patients. CLL patients can be divided into two subgroups (Ang-2 positive and Ang-2 negative CLL) with 30% of them displaying Ang-2 RNA levels above the cut off. A shorter progression-free survival was observed in Ang-2 positive CLL subset (p=0.032). Abnormal Ang-2 expression was also associated with unmutated IgV(H) genes (p<0.0001) and increased bone marrow angiogenesis (p=0.028), suggesting a role of Ang-2 in disease-progression of early CLL patients.     

Allogeneic stem cell transplantation following reduced-intensity conditioning can induce durable clinical and molecular remissions in relapsed lymphomas: pre-transplant disease status and histotype heavily influence outcome.

The safety and efficacy of reduced-intensity conditioning (RIC) followed by allogeneic stem cell transplantation (SCT) for relapsed lymphomas remains unresolved. We conducted a prospective, multicentered, phase II trial. A total of 170 relapsed/refractory lymphomas received a RIC regimen followed by SCT from sibling donors. The primary study end point was non-relapse mortality (NRM). Histologies were non-Hodgkin's lymphomas (NHL) (indolent (LG-NHL), n=63; aggressive (HG-NHL), n=61; mantle cell lymphoma (MCL), n=14) and Hodgkin's disease (HD, n=32). Median follow-up was 33 months (range, 12-82). The results show that frequencies were as follows: cumulative NRM at 3 years, 14%; acute and chronic graft-versus-host disease (GVHD) 35 and 52%, respectively; 3-year overall survival (OS), 69% for LG-NHL, 69% for HG-NHL, 45% for MCL and 32% for HD (P=0.058); and 3-year relapse incidence, 29, 31, 35 and 81%, respectively (P<0.001). Relapse risk differed significantly at 3 years between follicular lymphoma (FL) and chronic lymphocytic leukemia (CLL) (14 versus 46%, P=0.04). Molecular remission occurred in 94 and 40% (P=0.002) of patients with FL and CLL, respectively. On multivariate analysis, OS was influenced by chemorefractory disease (hazard ratio (HR)=3.6), diagnosis of HD (HR=3.5), and acute GVHD (HR=5.9). RIC allogeneic SCT is a feasible and effective salvage strategy in both indolent and aggressive NHL.     

Proliferation centers in chronic lymphocytic leukemia: correlation with cytogenetic and clinicobiological features in consecutive patients analyzed on tissue microarrays

To better define the significance of proliferation centers (PCs), the morphological hallmark of chronic lymphocytic leukemia (CLL), lymph node biopsies taken from 183 patients were submitted to histopathologic and fluorescence in situ hybridization (FISH) studies using a 5-probe panel on tissue microarrays. Seventy-five cases (40.9%) with confluent PCs were classified as 'PCs-rich' and 108 cases (59.1%) with scattered PCs were classified as 'typical'. Complete FISH data were obtained in 101 cases (55.1%), 79 of which (78.2%) displayed at least one chromosomal aberration. The incidence of each aberration was: 13q- 36,7%, 14q32 translocations 30.8%, 11q- 24.7%, trisomy 12 19.5% and 17p- 15.6%. Five cases showed extra copies of the 14q32 region. The 'PCs-rich' group was associated with 17p-, 14q32/IgH translocation, +12, Ki-67>30%. The median survival from the time of tissue biopsy for PCs-rich and typical groups was 11 and 64 months, respectively (P=0.00001). The PCs-rich pattern was the only predictive factor of an inferior survival at multivariate analysis (P=0.022). These findings establish an association between cytogenetic profile and the amount of PC in CLL, and show that this histopathologic characteristic is of value for risk assessment in patients with clinically significant adenopathy.     

Adverse prognostic features in chronic lymphocytic leukemia

Patients with chronic lymphocytic leukemia (CLL) can have variable courses, from indolent disease to rapid progression with limited response to treatment. The Rai and Binet staging systems were the first to classify patients into prognostic categories. Newer prognostic markers that correlate with shorter time to progression and time to treatment include elevated serum beta2M, TK, ZAP-70, and CD38, as well as unmutated IgV(H). Abnormal cytogenetics are found in the majority of patients with CLL. Del(17p), as well as mutations of TP53, is associated with an aggressive clinical course and short overall survival. Nearly one-fifth of patients have del(11q) and have a significantly shorter median progression-free survival; mutations in the ATM gene, located on 11q, may also have adverse prognostic implications. Intermediate-risk cytogenetic findings include trisomy 12 and del(6q). Patients with del(17p) should be evaluated for novel agents and/or allogeneic stem cell transplantation in first remission. Patients with del(11q) require treatment with an alkylating agent in addition to nucleoside analogs and rituximab, and patients with trisomy 12q may express higher levels of CD20, thereby making the malignant cells more susceptible to biologic agents that target CD20. Despite advances in stratifying patients and improved chemoimmunotherapeutic regimens, additional research in prognostication and treatment is needed.     

HLA-identical sibling allogeneic peripheral blood stem cell transplantation with reduced intensity conditioning compared to autologous peripheral blood stem cell transplantation for elderly patients with de novo acute myeloid leukemia.

We conducted a retrospective registry-based analysis to compare the outcome of 361 allogeneic human leukocyte antigen (HLA)-identical peripheral blood stem cell transplants (PBSCT) with reduced intensity conditioning (RIC) to that of 1369 autologous (auto) PBSCT in patients aged 50 years or older with de novo acute myeloid leukemia (AML), performed from 1997 until 2003 and reported to the European Group for Blood and Marrow Transplantation. Median age was 58 and 57 years in the RIC and auto groups, respectively. RIC patients had more advanced disease at the time of transplant. At a median follow-up of 24 months for RIC and 16 months for auto, multivariate analysis showed a lower risk for relapse (RR 0.77, P=0.013) without increased non-relapse mortality (NRM) in RIC patients (RR 1.26, P=0.28). Moreover, leukemia-free survival (RR 1.22, P=0.02) and overall survival (OS) (RR 1.32, P=0.005) were superior in the RIC group. In patients in 1st (CR), fewer relapses were counterbalanced by significantly increased NRM. Therefore, there was no survival advantage in this subgroup. In patients in 2nd or subsequent CR, LFS and OS were superior in the RIC group. RIC transplants show encouraging results in this older patient population with de novo AML.     

The importance of IGHV mutational status in del(11q) and del(17p) chronic lymphocytic leukemia

BACKGROUND: Most patients with CLL with a poor-risk cytogenetic profile have an unmutated IGHV sequence. Limited clinical information exists for patients with CLL who have a poor-risk cytogenetic profile and a mutated or good-risk IGHV status. We retrospectively screened all patients with CLL seen at our institution from 2006 onward who harbored a del(11q) or del(17p) CLL detected by fluorescence in situ hybridization (FISH) analysis for whom an IGHV analysis was requested. In 66 evaluable patients, 50 (76%) had an unmutated IGHV sequence. Thirty-nine patients (59%) had del(11q) and 27 patients (41%) had del(17p); no patient in this series had both del(11q) and del(17p). The patients' initial clinical presentations were similar in both mutational groups. Patients with an unmutated IGHV sequence were more likely to receive treatment and to have a shorter survival, with an estimated 3-year overall survival (OS) of 81% compared with 100% in the group with a mutated IGHV sequence (log rank, P = .06). These data suggest that IGHV mutational status has prognostic relevance even in patients with CLL who are defined as poor risk by genomic FISH analysis.     

Reduced-intensity conditioning lowers treatment-related mortality of allogeneic stem cell transplantation for chronic lymphocytic leukemia: a population-matched analysis.

To elucidate whether reduced-intensity conditioning (RIC) decreases treatment-related mortality (TRM) after allogeneic stem cell transplantation (allo-SCT) for chronic lymphocytic leukemia (CLL), we retrospectively compared 73 RIC cases from a recent EBMT survey with 82 patients from the EBMT database who had undergone standard myeloablative conditioning (MC) for CLL during the same time period. The two populations were matched by adjusting the primary risk factor, the conditioning regimen, in a series of Cox models for age, sex, donor type, remission status at transplant and analyzed for its effect on TRM, relapse incidence, event-free (EFS) and overall survival (OS). After adjustment, a significant reduction of TRM became evident for the RIC population (hazard ratio (HR) 0.4 (95% confidence interval 0.18-0.9); P=0.03). On the other hand, RIC was associated with an increased relapse incidence (HR 2.65 (0.98-7.12); P=0.054). There was no significant difference between RIC and MC in terms of EFS (HR 0.69 (0.38-1.25); P=0.22) and OS (HR 0.65 (0.33-1.28); P=0.21). We conclude that RIC appears to favorably influence TRM after allo-SCT for CLL. This observation, as well as possible detrimental effects of RIC on relapse risk, should be confirmed by prospective studies.     

Allogeneic transplantation following a reduced-intensity conditioning regimen in relapsed/refractory peripheral T-cell lymphomas: long-term remissions and response to donor lymphocyte infusions support the role of a graft-versus-lymphoma effect

Rescue chemotherapy or autologous stem cell transplantation (autoSCT) gives disappointing results in relapsed peripheral T-cell lymphomas (PTCLs). We have retrospectively evaluated the long-term outcome of 52 patients receiving allogeneic SCT for relapsed disease. Histologies were PTCL-not-otherwise specified (n=23), anaplastic large-cell lymphoma (n=11), angioimmunoblastic T-cell lymphomas (n=9) and rare subtypes (n=9). Patients were allografted from related siblings (n=33, 64%) or alternative donors (n=13 (25%) from unrelated and 6 (11%) from haploidentical family donors), following reduced-intensity conditioning (RIC) regimens including thiotepa, fludarabine and cyclophosphamide. Most of the patients had chemosensitive disease (n=39, 75%) and 27 (52%) failed a previous autoSCT. At a median follow-up of 67 months, 27 of 52 patients were found to be alive (52%) and 25 (48%) were dead (n=19 disease progression, n=6 non-relapse mortality (NRM)). The cumulative incidence (CI) of NRM was 12% at 5 years. Extensive chronic graft-versus-host disease increased the risk of NRM (33% versus 8%, P=0.04). The CI of relapse was 49% at 5 years, influenced by disease status at the time of allografting (P=0.0009) and treatment lines (P=0.007). Five-year overall survival and progression-free survival (PFS) were 50% (95% CI, 36 - 63%) and 40% (95% CI, 27 - 53%), respectively. The current PFS was 44% (95% CI, 30-57%). In all, 8 out of 12 patients (66%) who received donor-lymphocytes infusions for disease progression had a response. At multivariable analysis, refractory disease and age over 45 years were independent adverse prognostic factors. RIC allogeneic SCT is an effective salvage treatment with a better outcome for younger patients with chemosensitive disease.     

Markers of increased angiogenesis and their correlation with biological parameters identifying high-risk patients in early B-cell chronic lymphocytic leukemia

We wondered whether there was any association between the extent of increased angiogenesis and IgV(H) gene mutational status, expression of CD38 and ZAP-70 in early B-cell chronic lymphocytic leukemia (CLL) patients. Circulating levels of vascular endothelial growth factor (VEGF) correlated positively with ZAP-70-expression (P=0.03), CD38- expression (P=0.03) and mutational status of IgV(H) (P=0.005). The same did not apply when correlations were sought with either bone marrow angiogenesis or serum levels of basic fibroblatic growth factor (FGF-2). Studies to determine how to integrate variables reflecting increased angiogenesis with other prognostic markers such as CD38, ZAP-70, IgV(H) status and cytogenetic abnormalities are needed to optimize risk stratification for individual patients.     

Allogenic hematopoietic stem‐cell transplantation with reduced‐intensity conditioning in patients with refractory and recurrent multiple myeloma

BACKGROUND:

Allogeneic stem cell transplantation (SCT) with myeloablative conditioning is potentially curative therapy for myeloma, but is reportedly associated with a high risk of nonrecurrence mortality (NRM). Reduced‐intensity conditioning (RIC) allows for the reduction of NRM, but the recurrence rate is increased. The role and timing of allogeneic SCT in the disease course remains controversial. To the authors' knowledge, there are limited data regarding the long‐term outcome of RIC in the recurrent/refractory setting.

METHODS:

A retrospective analysis was conducted of SCT outcomes in 50 patients who received RIC for recurrent/refractory myeloma between the years 2001 and 2004. All patients were given fludarabine‐melphalan based conditioning and stem cell grafts from a related (n = 27) or unrelated donor (n = 23).

RESULTS:

The median age was 53 years. Forty‐seven patients failed a prior autologous SCT. Thirty patients were in disease remission at the time of SCT and 20 had stable or progressive disease. With a median follow‐up of 6.4 years (range, 5‐7.9 years), the overall and progression‐free survival (PFS) rates were 34% and 26%, respectively. The NRM rate was 26%. Adverse prognostic factors for survival included SCT not in remission, long duration of disease (>5 years from diagnosis), and transplantation from a female donor to a male recipient. The 7‐year PFS in 19 patients with none of these adverse prognostic factors was 47%. Chronic graft versus host disease and the achievement of complete remission after SCT were associated with improved outcome.

CONCLUSIONS:

Allogeneic SCT can result in long‐term PFS in a subset of myeloma patients who fail prior therapy and should be considered early after failure and after achieving remission. Cancer 2010. © 2010 American Cancer Society.     

Ex vivo drug and irradiation sensitivities in hypermutated and unmutated forms of chronic lymphocytic leukemia cells

Several investigators have now established that chronic lymphocytic leukemia (CLL) is not a uniform disease entity, since approximately half of the cases of CLL have undergone immunoglobulin V region (IgV) hypermutation, whereas the other half display unmutated Ig genes. The median survival time of mutated CLL (M-CLL) cases has been shown to be approximately twice as long as that for unmutated CLL (UM-CLL), but no clear explanation for this difference is currently available. In this work, we have investigated a cohort of previously untreated CLL patients, to see whether the ex vivo sensitivities of leukemic cells of 16 UM-CLL patients differ from those of 8 M-CLL patients, using nine different drugs and two types of irradiation. Our results demonstrated very similar ex vivo sensitivities and tumor cell heterogeneity of sensitivity of UM-CLL and M-CLL cells when tested against chlorambucil, 2-chloro-2'-deoxyadenosine, cyclosporin A, cis-platinum(II)diammine-dichloride, doxorubicin hydrochloride, 2-fluoroadenine-9-beta-D-arabinofuranoside, prednisolone sodium succinate, verapamil, vincristine, gamma-irradiation, and UV-irradiation. This indicates that de novo chemo/radiosensitivity cannot explain the survival difference observed between UM-CLL and M-CLL.     

Abnormalities of chromosomes 1p34-36, 4p16, 4q35, 9q11-32 and +7 represent novel recurrent cytogenetic rearrangements in chronic lymphocytic leukemia

Karyotypes were studied in over 250 cases of CLL seen at our Institution and 12 cases with a previously undescribed chromosome abnormality were identified. Cytogenetic and clinicobiological features in these patients are described. Fluorescence in situ hybridization using probes for the detection of +12 and deletions of 13q14, 17p13, and 11q22-23 was performed. Hematologic and clinical data were reviewed and a review of the literature was performed. Twelve patients were found carrying the following aberrations in the stemline: abnormalities at 1p34 (n = 2), 4p16 (n = 2), 4q35 (n = 2), 9q11-32 (n = 4) and +7 (n = 2). Trisomy 12 was found in 3 cases, whereas no case carried 13q-, 11q-, 17p-. Our data showed that (i) aberrations involving 1p34 and 4p16 as isolated chromosome anomalies were preferentially associated with early stage disease; (ii) 4q35 anomalies were associated with a relatively aggressive disease, atypical morphology and with monoclonal gammopathy; (iii) rearrangements of 9q were characterized by atypical morphology and aggressive disease with splenic involvement; (iv) +7 be may associated with +12. 1p34-36; 4p16; 4q35; 9q and chromosome 7 represent novel recurrent rearranged sites in CLL, with a 0.5-3% incidence. Transformation in these patients seemingly occured through a cytogenetic route not involving the classical CLL-associated chromosome regions. These chromosome rearrangements may be associated with peculiar hematologic features.     

Genetics of chronic lymphocytic leukemia: genomic aberrations and V(H) gene mutation status in pathogenesis and clinical course.

The genetic characterization of chronic lymphocytic leukemia (CLL) has made significant progress over the past few years. While conventional cytogenetic analyses only detected chromosome aberrations in 40-50% of cases, new molecular cytogenetic methods, such as fluorescence in situ hybridization (FISH), have greatly enhanced our ability to detect chromosomal abnormalities in CLL. Today, genomic aberrations are detected in over 80% of CLL cases. Genes potentially involved in the pathogenesis were identified with ATM in a subset of cases with 11q deletion and p53 in cases with 17p13 deletion. For the most frequent aberration, the deletion 13q14, candidate genes have been isolated. Genetic subgroups with distinct clinical features have been identified. 11q deletion is associated with marked lymphadenopathy and rapid disease progression. 17p deletion predicts for treatment failure with alkylating agents, as well as fludarabine and short survival times. In multivariate analysis 11q and 17p deletions provided independent prognostic information. Recently, another important issue of genetic risk classification in CLL was identified with the mutation status of the immunoglobulin variable heavy chain genes (V(H)). CLL cases with unmutated V(H) show more rapid disease progression and shorter survival times. Whether CD38 expression can serve as a surrogate marker for V(H) mutation status is currently discussed controversially. V(H) mutation status and genomic abnormalities, such as 17p and 11q deletion, have recently been shown to be related to each other, but were of independent prognostic information in multivariate analysis. Moreover, genomic aberrations and V(H) mutation status appear to give prognostic information irrespective of the clinical stage and may therefore allow a risk assessment for individual patients early in the course of their disease.     

Comparison between two fludarabine-based reduced-intensity conditioning regimens before allogeneic hematopoietic stem-cell transplantation: fludarabine/melphalan is associated with higher incidence of acute graft-versus-host disease and non-relapse mortality and lower incidence of relapse than fludarabine/busulfan.

Reduced-intensity conditioning (RIC) regimens are increasingly used in allogeneic stem-cell transplantation (SCT). There are no data whether any of these regimens has advantage and in what setting. We retrospectively analyzed SCT outcomes in 151 patients given fludarabine-based RIC for various hematological malignancies; 72 conditioned with fludarabine and intravenous-busulfan (FB) and 79 with fludarabine and melphalan (FM). FM was more myelosuppressive. Grade III-IV organ toxicity occurred in 31 and 53% of FB and FM recipients (P=0.005) and acute graft-versus-host disease grade II-IV in 33 and 53%, respectively (P=0.01). Non-relapse mortality rate (NRM) was 16 and 40%, respectively (P=0.003). Active disease (HR 2.2, P=0.003) and prior autologous SCT (HR 1.7, P=0.04) predicted inferior overall survival (OS). Among patients transplanted in remission, OS was 72 and 36% after FB and FM, respectively (P=0.03) due to increased NRM with FM. Similarly, patients transplanted in active disease experienced higher NRM with FM, however lower relapse rates resulted in equivalent OS. In conclusion, there are marked differences in outcome between RIC regimens that are theoretically dose-equivalent. The FM regimen is more myelosuppressive and toxic but controls disease better. FB was associated with improved survival in patients transplanted in remission. These observations merit further study in prospective studies.     

The effect of allogeneic stem cell transplantation on high risk chronic lymphocytic leukaemia: a single centre retrospective analysis

In recent years, many studies have confirmed that allogeneic stem cell transplantation (allo‐SCT) can provide long‐term disease control and possible cure in selected patients with chronic lymphocytic leukaemia (CLL), including those with a biologically highly unfavourable risk profile. A retrospective analysis of allo‐SCT in 30 patients with CLL whose risk profile was unfavourable and who were treated in the years 2000–2009 was performed. The aim was to compare the results of allo‐SCT by prognostic factors and conditioning type and evaluate the results of unrelated transplantation. The median age was 54 years. Donors were 8 HLA‐matched siblings and 22 unrelated volunteers, 11 of whom were mismatched. Eighteen patients were treated with reduced intensity conditioning. Twelve patients received myeloablative conditioning. Estimated overall survival (OS) at 3 years was 78%, progression‐free survival (PFS) 71%, relapse incidence 10% and non‐relapse mortality (NRM) 16%, respectively, with a median follow‐up of 35 months. According to molecular/cytogenetic characteristics, OS and PFS for the high risk group (17p‐ or 11q‐) were 89 and 77%, respectively, not significantly different from those with standard risk. Graft‐versus‐host disease (GVHD) was associated with greater toxicity; significantly higher NRM for patients with aGVHD (p = 0.04) and worse PFS for patients with cGVHD (p = 0.04). Our results for the refractory disease group (77% responses) indicate that chemoresistance may be overcome by the GVL effect. Transplants from unrelated donors may be considered comparable to those from related donors. Copyright © 2010 John Wiley & Sons, Ltd.     

Allogeneic hematopoietic stem cell transplant with reduced-intensity conditioning for chronic lymphocytic leukemia in Sweden: does donor T-cell engraftment 3 months after transplant predict survival?

Thirty-eight adult patients with chronic lymphocytic leukemia (CLL) underwent reduced-intensity conditioning (RIC) allogeneic stem cell transplant (allo-SCT) in Sweden between 1999 and 2007. The cumulative incidences of acute graft-versus-host disease (GVHD) grades II-IV and chronic GVHD were 29% and 47%, respectively. Rates of non-relapse mortality, progression-free survival (PFS) and overall survival (OS) were 18%, 47% and 74% at 1 year, and 21%, 25% and 45% at 5 years, respectively. T-cell chimerism after transplant was measured in 31 out of 34 patients (91%) surviving beyond day +100. Seventeen patients achieved >90% donor T-cell engraftment at 3 months after allo-SCT and, compared with the 12 patients with ≤90% donor T-cell engraftment, they showed favorable PFS at 1 year (82% vs. 33%, p =0.002) and better long-term PFS and OS (p =0.002 and 0.046, respectively). Donor T-cell engraftment of >90% at 3 months after RIC allo-SCT for CLL seems to predict favorable short-term and long-term outcome.     

Downregulated Dicer expression predicts poor prognosis in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the western world. Alterations in microRNAs (miRNAs) expression have been proposed to play a role in CLL pathogenesis. Dicer and Drosha are the main regulators of miRNA biogenesis, and deregulation of their expression has been indicated as a possible cause of miRNA alterations observed in various cancers. To investigate the role of Dicer and Drosha in CLL, we assessed the expression of Dicer and Drosha and their correlation with other prognostic factors, including Binet stages, immunoglobulin heavy chain variable gene (IGHV) mutation status, TP53 mutation status, ZAP-70 protein and CD38 expression level in 165 CLL patients by using real-time polymerase chain reaction methods. Patients with unmutated IGHV genes had significantly lower expression of Dicer than patients with IGHV mutations. The lower expression level of Dicer was also significantly associated with higher level of CD38 and ZAP-70, and more aggressive Binet stage. We also analyzed Dicer expression in different cytogenetic subgroups. Lower Dicer level was found in patients with unfavorable cytogenetic aberrations (deletion in 17p13 or 11q22.3) in contrast to higher level in good risk cytogenetics (deletion in 13q14 as the sole abnormality). Furthermore, the lower expression of Dicer in CLL shows a strong association with shorter overall survival (OS) (P = 0.0046) as well as with reduced treatment free survival (TFS) (P = 0.0006). By contrast, no differences in the expression of Drosha among these groups of patients were observed. Our data suggest that Dicer expression may play an important role in the progression and prognosis of CLL.