ALBERT

Description: Objectives: In patients with refractory chronic lymphocytic leukemia (CLL), the potential to cure is unique to allogeneic stem cell transplantation (HSCT). Clearance of minimal residual disease by suspected graft-versus-leukemia effects has been described elegantly and documented in several independent patient cohorts. Yet data from large numbers of patients which support the concept of cure by allogeneic transplantation have not been published. With the advent of new targeted therapies for patients with advanced chemo-refractory CLL, this information becomes crucial for clinical decision making and patient counselling. Therefore, we aimed at the description of long-term survival outcomes, and the estimation of excess mortality compared to the age- and sex-matched general population. Patients and Methods: Data from patients with CLL who had received a first allogeneic HSCT from an HLA-identical sibling (SIB) or alternative donor between January 2000 and December 2010, and who were registered with the EBMT database, were analyzed. Patients with Richter's syndrome and with syngeneic donors were excluded from this analysis. Survival probabilities were calculated by means of the Kaplan-Meier estimator both in the total population, and in patients who passed the 2- and 5-year landmark without previous relapse or progression. Excess mortality of the landmark populations compared to an age-, sex- and calendar year-matched general population was estimated with a Cox regression model for relative survival using the R-package relsurv. Results: In total 2589 patients were included into the analysis. The median follow-up of patients alive at the end of follow-up was 4.0 years (range: 1 to 161 months). The median age at HSCT was 55 years (range: 12 to 74 years). One hundred and fifty eight patients (6.1%) were below 40 years of age at the time of transplantation. Seventy-four percent of patients were male. The remission status at the time of transplantation was reported as complete remission in 15%, partial remission in 47%, and stable disease or progressive disease in 32%. Information on the remission status was not available for 6% of the patients. Fifty-one percent of the patients had an HLA-matched sibling donor and seventy-seven percent of patients received reduced-intensity conditioning. For the whole cohort of patients, the 5- and 10-year overall survival (OS), progression-free survival (PFS), and non-relapse mortality (NRM) were 45%, 35%, 36%, and 35%, 28%, 40%, respectively. The cumulative incidence of relapse (CIR) was 21% at two years, 29% at five years, and 32% at ten years. A total of 1023 patients and 394 patients were alive without relapse or progression, and in follow-up at two and five years after HSCT. Five years after patients had passed the 2- and 5-year landmark, OS, CIR and NRM were 73%, 22%, 16%, and 83%, 11%, 10% respectively. Compared to the general population excess mortality of the 5-year landmark population in the subsequent five years was estimated to be 3% for male patients at an age of 45 years, 10% for male patients at an age of 55 years, and 24% for male patients at an age of 65 years (see Figure 1). For female patients in this 5-year landmark population, the corresponding excess mortality rates were 4%, 11%, and 27%. Patients without progression and with CR at any time from HSCT to the two and five-year landmarks had a slightly better outcome than those who had never had CR. Surprisingly, this was not a result of a lower CIR but of a lower NRM. Conclusion: Long-term follow-up data derived from the EBMT registry show a steady decline in hazard of relapse after allogeneic HSCT, yet relapse continues to be a threat. Moreover, even patients alive and disease-free after 5 years are still confronted with substantial NRM. These results show that there is room for improvement of long-term patient care. By comparing mortality of younger patients who passed the 5-year landmark with the general population, only marginal excess mortality was observed, while elderly patients still had substantial excess mortality beyond this landmark. Nevertheless, the results indicate that a significant fraction of patients can be cured by allogeneic HSCT. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Description: Abstract 1239 Background. Imatinib (IM), a selective BCR-ABL tyrosine kinase inhibitor (TKI), is a treatment of choice for newly diagnosed chronic myeloid leukemia (CML) patients (pts) in chronic phase (CP) as it was shown in the IRIS trial. The treatment strategy and response evaluation is based on NCCN or ELN guidelines. Only limited “real life” data of IM impact on pts outcome as well as ELN (European LeukemiaNet) recommendations applicability in daily practice has been published. In the Czech as well as in the Slovak Republic (15 million inhabitants), the treatment of CML patients is centralized in overall 13 centers, capable carrying on both the treatment and laboratory monitoring. There are two CML prospective projects CAMELIA and INFINITY focused on CML pts analysis. Aims. To analyze the treatment response and long-term outcome in consecutive, unselected patients with CP-CML treated with IM and to evaluate the prognostic role of ELN 2006 and 2009 response evaluation. To analyze molecular response in more detail. Methods. Altogether 458 consecutively included patients in INFINITY (152 pts) and CAMELIA projects (306 pts) were assessed. For the treatment response evaluation the ELN 2006 and ELN 2009 definitions were used. We assessed rates and the cumulative incidences of complete hematologic responses (CHR), complete cytogenetic responses (CCyR), major (MMoR) and complete molecular responses (CMoR). Overall survival (OS) was defined as the time from the start of IM to death from any cause, overall survival CML-related death (OSCML), transformation-free survival (TFS) as survival without evidence of AP or BP or death from any cause, progression-free survival (PFS) as survival without evidence of AP or BP, loss of CHR, MCyR, increasing white blood cell count or death fron any cause while on IM treatment and event-free survival (EFS) –events defined as a progression (the same as in PFS, as described above), loss of CCyR, failure to achieve CHR at 6 months, MCyR at 12 months and CCyR at 18 months, or intolerance of IM as the cause its discontinution. The patient survival according to MMoR achievement and the cumulative incidence of MMoR according to different BCR-ABL ratio within the first 3 months of IM therapy was analysed. Kaplan-Meier cumulative incidence methods and log rank test were used for survival statistic analysis. Results. A total of 458 patients (median age 52 year;17-81) treated with IM between 2003–2009 were analysed.The median follow-up was 33.1 months (1.4-82.1). At 2 and 4 years the cumulative incidence of CHR was 90.9% and 94.7%, CCyR 64.9% and 76%, MMR 52.4% and 68.1% and CMR 24.5% and 43%, respectively. In 4 years estimated OS was 91.1%, OSCML 96.6%, TFS 93.9%, PFS 83.2% and EFS 66%. According to ELN 2006 criteria the optimal response (OR) by 6 months (defined as PCyR) and by 12 months (defined as CCyR) resp. had significant impact on PFS (p=0.04 and p

Description: Introduction:Even in the era of novel targeted therapies for the treatment of Chronic Lymphocytic Leukemia (CLL) patients, such as BTK, PI3K and BCL2 inhibitors, allogeneic hematopoietic stem cell transplantations (alloHCT) will remain an important treatment option for a subset of patients with very high risk CLL. The current study focused on the impact of center and procedure-related factors on outcomes after alloHCT, taking into account the impact of patient- and disease-related risk factors. Patients and Methods:Data of 684 CLL patients who received a first alloHCT between 2000 and 2011 were analyzed. Their data were collected as part of the EBMT CLL Data Quality Initiative. Outcomes of interest were Event-Free Survival (EFS) up to 5 years after transplantation and mortality in the first 100 days after alloHCT. Outcomes were analyzed by means of the Kaplan-Meier method and Cox proportional hazards models with a frailty (random effects) component to take into account unexplained center heterogeneity. The following factors describing center characteristics or the transplant procedure were analyzed: experience in alloHCT in general and, for CLL specifically, accreditation by the Joint Accreditation Committee-ISCT & EBMT (JACIE), Gross National Income (GNI)/capita based on purchasing power parity (PPP) (GNI/cap), donor type, donor-patient sex-match, type of conditioning, stem cell source and T-cell depletion (TCD). Results:Five-year EFS of the whole cohort was 37% (95% Confidence Interval, 33%-42%), Day-100 survival was 90% (88%-92%). Experience of the transplant center was measured by the number of all alloHCTs, and alloHCTs for patients with CLL respectively. The median total number of alloHCTs per center per year was 45 (range 0-169) and the median number of CLL alloHCTs was only 2 per center per year (range 0-19). Greater experience with transplantation of patients with CLL (Hazard Ratio (HR) 0.96 per additional transplant, p=0.002), JACIE accreditation (HR 0.7, p=0.045) and a higher GNI/cap (HR 0.4, 95% CI 0.2-0.96, p=0.04) showed a protective impact on 5-year EFS in the Cox model. In vivo TCD with alemtuzumab (HR 1.5 compared to no TCD, p=0.03) and a female donor for a male patient (HR 1.4 compared to a male donor for a male patient, p=0.02) were the only procedure-related factors significantly associated with EFS. Event-Free Survival after in vivo TCD with Anti-Thymocyte-Globulin or after ex vivo TCD was comparable to EFS without TCD (HR 0.9, 0.7-1.3, p=0.6; HR 0.9, 0.5-1.6, p=0.8). Non-myeloablative conditioning did not have a negative impact on 5-year EFS, and exposed patients to a lower risk of non-relapse mortality. Measured and unmeasured center characteristics did not have a significant impact on 100-day mortality. Even when correcting for patient-, procedure- and center-related characteristics, there was still significant variation in center outcome, expressed by center-specific HRs derived from the frailty models, ranging from 0.6 to 1.2. Their impact is illustrated in a model-based plot for EFS (see Figure) which shows outcomes for three reference patients with the same characteristics who would be transplanted in three centers with the same measured characteristics but with the highest, average and lowest HRs in the dataset. These unexplained center effects likely represent a mixture of differences which could apply to the location of the transplant center, unmeasured characteristics of the patient population transplanted at this center, selection criteria which were not reported and factors determining the success of the transplant procedure which might differ between centers. Conclusion: We have confirmed that both center- and procedure-related factors have a significant impact on the EFS of patients with CLL undergoing alloHCT. Our results may help to interpret outcomes of single or multicenter studies better. Since non-myeloablative conditioning did not have a negative impact on EFS and exposed patients to a lower risk of non-relapse mortality, this approach should be favored for future alloHCT for CLL. Probability of Event-Free Survival up to Five Years Post-HCT for three Reference Patients Contribution: J.S. designed the research and wrote the paper. L.C.d.W conducted the statistical analysis and produced the figure. Figure Figure. Disclosures Schetelig: Sanofi: Honoraria. Gramatzki:Janssen: Other: Travel/Accommodation/Expenses, Research Funding. Dreger:Gilead: Consultancy; Gilead: Speakers Bureau; Janssen: Consultancy; Novartis: Speakers Bureau; Novartis: Consultancy; Roche: Consultancy.

Description: Abstract 4905 Modern molecular diagnostic techniques allow the detection of minimal residual disease (MRD) in hematological malignancies with high sensitivity, allowing patient-specific assays of MRD levels over the course of treatment. One challenge for these techniques is finding appropriate MRD marker targets. For instance, PCR-based MRD analysis requires unique sequence-specific information for the malignant clone of interest. In many acute leukemias, such detailed information is lacking, either because no abnormality is detected (e.g. in 40–50% of adult Acute myeloid leukemia-AML), or the resolution of cytogenetic methods is too low to precisely define newly-found abnormalities. We have used multicolor-FISH (mFISH) to perform karyotyping of 141 patients. Using this approach we have identified chromosomal abnormalities in about 35% of analyzed cases. The aberrations found involved the recurrent aberrations t(15;17), t(8;21), inv(16), t(9;22),−5q, −7, +8 but also an array of unique abnormalities, such as der(15)t(5;15)(q15;q24), t(6;12)(p22;q13), and der(17)t(12;17)(q14;pter), which may serve as possible targets for molecular MRD follow-up. To further characterize such targets, we seek to bridge the gap from cytogenetic resolution down to higher-resolution molecular techniques. For this, we first employ the mBAND technique, followed by multicolor FISH using DNA probes with known cytogenetic location. These probes are drawn from the Human Minimal Genomic Clone Set (Version 1.0, Source Bioscience LifeSciences) of over 25,000 bacterial artificial chromosome (BAC) clones with human DNA inserts. These are tiling clones covering almost 100% of the genome, and therefore allow us to develop FISH probes to regions containing almost any conceivable target breakpoint. Starting with breakpoint information from mFISH/mBAND, we perform consecutive multi-color/multi-BAC hybridizations around the region of interest, looking for breakpoint-spanning probes. Using this system, we are able to move from a resolution of around 2 Mbp (the limit of mBAND) to the resolution of individual BAC clones (average 150 kbp) in three hybridizations. To achieve further resolution, long-range PCR products are designed within the region defined by breakpoint-spanning BACs, with labeling and FISH-mapping of these probes. At present, we are starting to perform these hybridizations on stretched DNA (fiber-FISH or combed DNA), where one micrometer of a stretched DNA molecule represents about 2000 base pairs, allowing visualization of probe distance and spacing, and even higher-resolution breakpoint analysis. Chromosome microdissection followed by high-throughput sequencing (Roche GS Junior) is also being pursued to identify novel breakpoints by rapidly sequencing large chromosomal regions on both sides of a translocation. The final goal is to map genomic abnormalities to a resolution amenable to long-range PCR, yielding specific targets for MRD detection, and allowing clone-specific Real-Time PCR assays for sensitive and specific monitoring of MRD in hematooncological patients. Disclosures: Smolej: GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees, Travel Grants; Roche: Honoraria, Travel Grants; Genzyme: Honoraria, Travel Grants.

Description: Objectives: For medically-fit young patients with high-risk chronic lymphocytic leukemia (CLL) BTK-/PI3K-inhibitors or allogeneic stem cell transplantation (alloHCT) are considered. We hypothesized that given the choice between these drugs and transplantation in future only patients with a low risk of treatment failure will be selected for alloHCT. Therefore, we searched for risk factors for 2-year non-relapse mortality (NRM) and 5-year event-free survival (EFS) after alloHCT, the latter as a surrogate for long-term disease-control. Methods: Data from patients with CLL who had received a first alloHCT from a HLA-identical sibling (SIB) or unrelated donor between 2000 and 2011 were updated in an EBMT data quality initiative. Multivariable Cox regression models were fitted to assess the impact of baseline risk factors for NRM and EFS. Results: Data on 694 patients were included into the analysis. The median age of the cohort of patients was 55 years (19 years to 74 years). Seventy-nine percent of patients had a Karnofsky performance status of 90% or higher. A disease history of less than two years was reported in 20% of patients and 44% of patients had a disease history of more than 5 years. The median number of pretreatments was 3 (range, 0-15). Eleven percent of patients had received a previous autologous HCT. Only 9% of patients had never received purine-analogs (PA) during their treatment history. Sixty-three percent of patients had either PA-refractory disease or relapse within 24 months from the last PA-containing chemotherapy at the time of HCT. A deletion 17p had been diagnosed in 28% of patients in this cohort. Information on PA-sensitivity, early relapse after autologous transplantation or PA-combination therapy and del(17p)/TP53 is used to select patients for allogeneic HCT according to the EBMT 2007 consensus. EBMT consensus criteria were met in 76% of evaluable patients. Overall, the majority of patients analyzed in this subset of all registered patients had high-risk CLL. For the whole cohort 2-year NRM was 28% (95%-CI, 24% to 32%). The baseline risk factors age, Karnofsky performance status, donor type, and donor-recipient sex mismatch had a significant impact on 2-year-NRM. With the help of these risk factors the outcome of good risk and poor risk reference patients was predicted whose linear predictors were close to the 10th and the 90th percentile of all patients in the dataset. The good risk male reference patient has an age of 45 years, a Karnofsky performance index of 100%, is in partial remission at HCT and has a matched related male donor. The poor risk male reference patient has 55 years of age a Karnofsky performance index of 80%, SD/PD at HCT, and a matched unrelated female donor. The female reference patients had the same characteristics, apart from the donor sex. Two-year-NRM was predicted to be 11% (12%) for male (female) patients with a favorable risk compared to 40% (32%) with a poor risk profile (see Figure). The same approach was used to analyze risk factors for long-term disease control. Five-year-EFS was 37% (95%-CI, 33% to 41%) for all patients. Age, Karnofsky performance status, history of an autologous HCT, remission status, and donor-recipient sex mismatch had a significant impact. The model-based prediction of 5-year EFS was 54% (64%) for a male (female) patient with a favorable risk profile compared to 15% (30%) with a poor risk profile. Current knowledge suggests that allogeneic HCT can overcome the negative prognostic impact of high risk cytogenetic abnormalities, especially of a deletion(17p) or TP53 -mutation. Even in this large cohort we observed only a trend for a lower incidence of relapse/progression in patients without deletion(17p) CLL within the first two years after HCT with translated into a trend for better EFS at that time. The impact on long-term disease-control and mortality was even smaller. Conclusion: Information on predicted 2-year-NRM and 5-year-EFS for good and poor risk reference patients derived from a large CLL dataset may be instrumental to select patients for future alloHCT. Model-based prediction of non-relapse mortality and relapse/progression. Figure 1. Figure 1. Figure 2. Figure 2. Disclosures No relevant conflicts of interest to declare.

Description: Abstract 2526 Many studies on childhood and adult leukemias have demonstrated that thorough molecular analysis at the time of diagnosis and minimal residual disease (MRD) follow-up are significantly related to the prognosis, and overall- and event-free survival, of patients with acute leukemias. In acute myeloid leukemia (AML), such complex molecular diagnostics and subsequent MRD evaluations are important factors for proper stratification, disease prognosis, assessment of the treatment response, optimal dosage and duration of chemotherapy, and estimation of the optimal timing for hematopoietic stem cell transplantation. Upon diagnosis, the bone marrow samples of AML patients are routinely screened for an array of recurrent chromosomal abnormalities, including chromosomal translocations (e.g. PML/RARa, AML1/ETO, CBFb/MYH11, MLL fusions, BCR/ABL) or leukemia-associated genetic mutations (e.g. mutations in genes NPM1, WT1, FLT3, MLL or CEBPa). Given the fact that laboratories often deal with a limited amount of material sampled for molecular investigations, and the number of possible genomic aberrations and molecular targets is high, it is desirable to implement in routine practice a flexible tool that allows testing for as many genetic abnormalities as possible, while reducing the amount of biological material required for analyses to a minimum. In our laboratory, we have developed a multiplex Real-Time PCR technique allowing us to examine over 75 recurrent chromosomal aberrations in only 10 multiplex PCR reactions (Table 1). The methodology makes use of a set of fluorescently labeled TaqMan hybridization probes, labeled by 5 different fluorophores. Using this methodology we are able to assess the presence of both rare as well as recurrent chromosomal translocations/aberrations in one setting, from a limited amount of starting material. This approach is not only extremely beneficial for the leukemic patient - which is always the primary goal - but also for the overall budgeting of routine molecular screening of diagnostic AML samples.Table 1:List of the AML-associated chromosomal abnormalities included in the 5-Color Multiplex Real-Time PCR system. The multiplexing of individual molecular targets is indicated by the individual PCR tubes (A to J) used in the diagnostic screening of AML in our laboratory. Importantly, a clone-specific chromosomal abnormality found at the time of diagnosis using our 5-Color Multiplex Real-Time PCR system allows us to molecularly follow-up the MRD level with a high sensitivity of 10e-4 to 10e-6, as assessed by serial dilutions of cloned standards harboring the individual aberrant genetic targets. This complex molecular approach considerably helps hematooncologists in clinical decision making and the adjustment and modulation of the treatment of AML patients in respect to their individual needs and their individual disease course. Since 2005 we have molecularly investigated 398 adult AML cases. Using the 5-Color Multiplex Real-Time PCR technique and mutational screening we were able to identify a clone-specific abnormality in 45.2% of cases. The clone-specific genetic markers were then used as specific molecular targets for a clone-specific MRD follow-up. Although in approximately 50% of AML patients we are still not able to identify any clone-specific abnormality to be used for either stratification (recurrent abnormalities) or molecular MRD follow-up (both recurrent and unique/rare abnormalities) of these leukemic patients, our 5-Color Multiplex Real-Time PCR system, being an open platform, enables us to flexibly implement any newly identified chromosomal aberrations to the diagnostic portfolio, thus increase the probability of finding a clone-specific molecular marker with all the positive consequences in respect to the management of patients with acute leukemia. Disclosures: Smolej: GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees, Travel Grants; Roche: Honoraria, Travel Grants; Genzyme: Honoraria, Travel Grants.