Kooperativer Bibliotheksverbund

In: Blood, American Society of Hematology, Vol. 114, No. 22 ( 2009-11-20), p. 1933-1933

Abstract: Abstract 1933 Poster Board I-956 According to the 2008 WHO Classification, mantle cell lymphoma (MCL) most likely derives from neoplastic transformation of a peripheral B cell of the inner mantle zone, mostly of naïve pre-germinal center type. Analysis of the immunoglobulin (IG) repertoire in MCL has revealed a bias in IG heavy variable (IGHV) gene usage and a predominance of unmutated rearrangements, with a variable minor proportion of cases carrying mutated IGHV genes (according to the 98% identity cutoff). However, limited knowledge exists regarding antigen-binding site sequence restrictions or specific somatic hypermutation (SHM) patterns in MCL. We examined the productive IGHV-D-J rearrangements of 651 MCL cases (including 398 cases from the European MCL Network), the largest series to date. We confirm and significantly extend previous observations that the IGHV gene repertoire is remarkably biased, with only three genes accounting for 40.3% of cases (IGHV3-21, 16.7%; IGHV4-34, 15.3%; IGHV1-8: 8.3%). Using bioinformatics approaches previously applied to CLL, biased associations of certain IGHV, IGHD and IGHJ genes with restricted (stereotyped) heavy complementarity-determining regions (HCDR3s) were identified in 68/651 cases (10.4%). Overall, 24 subsets of cases with stereotyped HCDR3s were recognized. Eight of 24 subsets included 3-7 cases each (“confirmed”), while the remaining 16 subsets included two cases each and were considered “provisional”. Stereotyped HCDR3s were found predominantly amongst rearrangements utilizing the IGHV3-21 and IGHV4-34 genes and the IGHJ6 gene. Notably, the MCL HCDR3 stereotypes identified here were distinct from those previously reported in CLL. Based on SHM analysis, the sequences were divided into three groups: (i) truly unmutated (100% germline identity, GI): 189/651 sequences (29.2%); (ii) minimally/borderline mutated (98-99.9% GI): 306/651 sequences (47%); and (iii) mutated ( 〈 98% GI): 155/651 sequences (23.8%), of which 93 had a GI 〈 97%. In keeping with previous reports, the IGHV gene repertoire of the three identity groups differed considerably. For instance, the IGHV3-21 gene was used by 7% of rearrangements with 〈 98% identity vs. 22.8% of rearrangements with 100% identity. In contrast, the IGHV3-23 gene was over-represented among mutated rearrangements (26.4%). Shared (“stereotyped”) amino acid (AA) changes across the entire IGHV gene sequence were identified for certain groups of sequences, especially those utilizing the IGHV1-8, IGHV3-21 and IGHV3-23 genes. A comparison to published series from other entities, in particular CLL, revealed that several stereotyped mutations identified in MCL were “disease-biased”. Importantly, stereotyped AA changes were also observed in the borderline or minimally mutated groups, indicating that even a low level of mutations may be functionally relevant. In conclusion, MCL is characterized by a highly distinctive IG gene repertoire with restricted HCDR3s and very precisely targeted and, probably, functionally driven SHM, strongly implying a role for antigen-driven selection of the clonogenic progenitors. Based on the evidence presented here, an antigen-driven origin of MCL could be envisaged, at least for subsets of cases. Disclosures: No relevant conflicts of interest to declare.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V114.22.1933.1933

Language: English

Publisher: American Society of Hematology

Publication Date: 2009

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 106, No. 11 ( 2005-11-16), p. 714-714

Abstract: Introduction: Ongoing studies suggest, that myeloablative conditioning chemotherapie with autologous SCT is not a curative treatment option in high risk CLL patients. For this reason a method to predict progression free survival (pfs) in individual patients (pts) is desirable. Minimal residual disease (MRD) short after auto SCT in pts with CLL are known to be homogeneous low with increasing MRD level at later time points. Early MRD increase is associated with clinical risk factors and high risk for clinical relapse. Methods: To estimate time to progression in individual patients we studied MRD kinetics between 12 and 36 months after SCT (observation period) by quantitative ASO-primer IgH PCR and/or MRD flow in 37 poor risk CLL pts (5 % with mutated IgH, advanced Binet stage, high lymphocyte count). We postulated LOG-linear growth kinetics from 12 months after SCT until clinical relapse, which allowed calculation of time to predicted hematologic relapse (pHR) after auto SCT. All patients were in clinical remission before myeloablative conditioning regimen of TBI and high-dose cyclophosphamide following autologous SCT. 16/37 pts. with relapsed disease served as a control group whereas 21 pts in continuing clinical remission defined an observation group. LOG-MRD kinetics were described by a linear standard curve defined by 2 or more samples of patients in clinical remission more than 6 months (mos) apart. Significant MRD change was defined by a change of more than 0.5 orders of magnitude within the observation time. By this standard curve time to pHR, defined as a CLL level of 0.5 (i.e. 50% of all blood cells are CLL cells), was estimated. Results: 28 of all 37 pts. showed increasing, 4 stable and 5 decreasing MRD level during the observation period. In the control group of 16 pts. with clinical relapse, MRD level of one pt. remained stable until 36 mos after SCT, whereas 15 pts. showed significant MRD increase with a median slope of 0.093 (0.04 to 0.25) LOG-MRD level and a median time to pHR of 51 (27 – 92) mos compared to an observed median pfs of 39 (28 – 64) mos after SCT (ns). Median difference between pfs and time to pHR was 3.5 (5.4 – 60) mos. Only in 5 of 15 pts this difference exceeded 12 mos of whom all relapsed earlier than the estimated time point. In the observation group of 21 pts 9 (4 and 5 respectively) pts showed stable MRD level or significant MRD decrease. 12/21 pts showed significant MRD increase with a median slope of 0.08 (0.03 – 0.17) and a median time to pHR of 57 (28 – 160) mos. Only in 2/12 pts the clinical relapse preceded the pHR (0.4 and 7.4 mos) within the median clinical follow up period of 45 (25 – 69) mos. Conclusions: LOG-linear MRD models can characterize CLL increase from 12 momths after SCT: Increasing MRD kinetics predict the time to clinical relapse with acceptable accuracy in the majority of CLL pts, although this simple model tends to overestimate the time to relapse. Further improvement of the model, e.g. by calculating absolute CLL numbers and/or by more sophisticated statistical methods might minimize this error. Nevertheless, this overestimation might also be caused by biological reasons, e.g. clonal evolution or subclone selection.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V106.11.714.714

Language: English

Publisher: American Society of Hematology

Publication Date: 2005

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 114, No. 22 ( 2009-11-20), p. 317-317

Abstract: Abstract 317 Evidence for Antigen-driven Development of Molecularly Classified Burkitt Lymphomas The presence of somatic mutations and intraclonal diversity (ID) in the variable region of rearranged immunoglobulin (Ig) genes is commonly used as a marker of the cellular passage of B cells through the germinal center (GC) reaction in secondary lymphoid tissues following an in vivo antigen encounter. Such features have also been documented in different subgroups of aggressive B-cell lymphomas, suggesting that antigen selection pressure has taken place during lymphoma development. We undertook a detailed analysis of the Ig repertoire and somatic hypermutation (SHM) status of 54 molecularly classified Burkitt lymphomas (BL) (Hummel et al. 2006). The IGHV gene repertoire was remarkably biased, with only three genes accounting for 40.8% of all cases (IGHV4-34, 18.5%; IGHV4-39, 11.1%; IGHV3-30, 11.1%). Of note, this bias was even more evident when cases were grouped according to age 〈 or 〉 14 years, with the IGVH4-34 and IGVH4-39 rearrangements occurring almost exclusively in pediatric BL (7/11 and 5/6 cases respectively). Only 2/54 cases (3.7%) carried unmutated IGHV genes (100% germline identity, GI); 12/54 cases (22.2%) carried IGHV genes of borderline/minimally mutated status (98–99.9% GI); finally, the remaining 40/54 cases (74.1%) carried mutated IGHV genes ( 〈 98% GI). The median GI of the cohort was 95.2% (range: 86.4–100%) with a significantly different mutation load according to age below or above 14 years (GI 95.8 vs. 92.9 respectively, p=0.0168). Shared replacement mutations (“stereotyped” amino acid (AA) changes) at certain codon positions were identified in 12/54 (22.2%) BL cases. Stereotyped AA changes were found only amongst rearrangements utilizing the IGHV4-34 and IGHV4-39 genes, strongly indicating evidence for an antigen driven SHM process in BL. The majority of stereotyped AA changes identified here were distinct from those previously reported in other entities, in particular CLL, and thus can be considered as BL-biased. Also, of note, the IGVH4-34 specific motif responsible for binding the N-acetyl-lactosamine antigenic determinant was found intact in 11 IGVH4-34 BL sequences, implying that these clones retained the ability to bind to and be activated by superantigens. Furthermore, the distribution of mutations was different in IGHV4-34 vs. non-IGHV4-34 cases, as evidenced by low R-to-S ratios in the heavy complementarity-determining regions (especially HCDR1), indicating a different selection pattern of VH-genes according to varying antigens. To assess the presence of ID through ongoing SHM, we evaluated 411 subcloned sequences from 11 IGVH4-34 and 6 IGVH4-39 cases. Only one case carried identical sets of subcloned sequences; seven cases carried mutations in single subcloned sequences that were considered as unconfirmed; finally, 9 cases carried at least one confirmed mutation among two or more subcloned sequences and, thus, were considered as exhibiting confirmed ID. However, analysis of the distribution of the so called unconfirmed changes provided further evidence for the very precise targeting of mutations introduced as part of the ID process. Thus, certain changes identified in single subcloned sequences from one case were shared by most or all subcloned sequences of another case utilizing the same IGHV gene (“confirmed by another case”). In conclusion, our data demonstrate that BL is characterized by a highly distinctive IG gene repertoire with a precisely targeted SHM process. In addition, they provide strong evidence for a functionally driven SHM, supporting a role for antigen-driven selection of the clonogenic progenitors. Disclosures: No relevant conflicts of interest to declare.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V114.22.317.317

Language: English

Publisher: American Society of Hematology

Publication Date: 2009

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 110, No. 11 ( 2007-11-16), p. 2799-2799

Abstract: Background: Adult patients with relapsed acute lymphoblastic leukemia (ALL) are candidates for allogeneic stem cell transplantation (SCT), if feasible. Despite the intensity of SCT treatment at least 40% of patients relapse. Survival is additionally negatively influenced by a high transplant related mortality. Therefore, markers that distinguish patients who will benefit from SCT from those who might profit from different therapeutic modalities or modification of SCT are highly warranted. Kinetics of minimal residual disease (MRD) can serve as molecular parameter of chemoresistance of the leukemia. The purpose of the current study was to investigate whether molecular resistance to front-line therapy can be overcome by allo-SCT following myeloablative conditioning. Methods: MRD was analyzed before and after myeloablative SCT in adult patients with Philadelphia negative relapsed ALL. MRD kinetics were compared to previous molecular response to first-line treatment. For this purpose, cases with persistent detectable disease 〉 1×E–04 at day+71/112 of first-line therapy were classified as primarily molecularly chemoresistant (PMR), cases with MRD values below 1×E–04 around day+71/112 of first-line treatment were categorized as primarily molecularly chemosensitive (PMS). Relapsed ALL patients were included if they had been treated according to the GMALL trials 06/99 or 07/03 with prospective MRD monitoring, and if they had bone marrow samples taken after relapse until day+100 after SCT. Real-time quantitative (RQ)-PCR analysis of patient specific immunoglobulin and T-cell receptor gene rearrangements were used as targets for quantification of MRD. Results: 25 patients were eligible (15 T- and 10 B-lineage ALL). Median age was 22 (16–45) years. Median disease-free survival after front-line therapy was 17 (3 to 52) months. Eleven cases were classified as molecularly chemoresistant to front-line therapy, 14 ALL cases were categorized as primarily molecularly chemosensitive. In keeping with molecular response to initial treatment, PMR cases showed only a modest reduction of MRD in response to salvage chemotherapy with a median MRD value of 3×E–01 (range 2×E–03 to 1×E+00) before SCT. Median MRD levels within the first 100 days after myeloablative SCT decreased to 4×E–04 with a range between MRD negativity and 1.0×E+00. PMS cases showed a significantly better response to salvage chemotherapy: In contrast to PMR cases who were MRD positive prior to SCT in all analysed cases, four out of 7 PMS cases were MRD negative pre-SCT (range: MRD negativity to 4.2×E–03). Also within 100 days after SCT 13/16 analysed samples were MRD negative (compared to only 4/11 analysed PMR samples, p=0.02, see Figure). Taken together, these results show for relapsed ALL that molecular chemoresistance to front-line therapy correlates with a poor molecular response to second-line treatment in transplant recipients. Figure Figure

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V110.11.2799.2799

Language: English

Publisher: American Society of Hematology

Publication Date: 2007

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 4376-4376

Abstract: The existence of stereotyped B cell receptor immunoglobulins (BcR IG) in chronic lymphocytic leukemia (CLL) strongly implicated antigen selection in disease ontogeny. We have previously shown that the stereotyped fraction encompasses ~30% of all CLL and includes multiple subsets with distinct BcR IG configuration and variable size. Eventually, certain major subsets emerged as distinct clinical entities, exemplified by subset #2 (IGHV3-21/IGLV3-21, ~2.5-3% of all CLL, mixed somatic hypermutation (SHM) status) of a particularly aggressive clinical course, thus, sharply contrasting subset #4 (IGHV4-34/IGKV2-30, ~1% of all CLL, mutated IGHV genes, M-CLL), a prototype for indolent disease. Here, taking advantage of a multi-institutional cohort of 21,123 CLL IG rearrangements, almost three times the size of the largest previous study, and the availability of validated, purpose-built immunoinformatics methods, we reappraised BcR IG stereotypy especially focusing on major subsets and the degree of their sequence similarity to related minor subsets. Stereotypy discovery was performed with ARResT/Teiresias, while stereotypy assignment to existing subsets previously deemed as major was performed with ARResT/AssignSubsets (http://bat.infspire.org/arrest/). In the present study, a subset was characterized as major if representing 〉 0.2% of the cohort (i.e. at least 50 cases). Minor subsets closely related to major ones (termed satellite) were identified applying the following criteria: (i) usage of IGHV genes from the same phylogenetic clan; (ii) VH CDR3 length difference ranging from -2 to +2 compared to the respective major subset; (iii) shared VH CDR3 sequence motif; and, (iv) -2 to +2 difference in the offset of the VH CDR3 motif compared to the respective major subset. In total, 7378/21123 (34.9%) IG sequences were grouped into subsets with stereotyped VH CDR3, with the previously characterized 19 major subsets accounting collectively for 2594 sequences (12.3%) of the cohort: of these, 12 included cases with unmutated IGHV genes (U-CLL), 6 concerned M-CLL and 1 (subset #2) included cases with mixed SHM status. Four additional subsets exceeded 50 cases, and, thus, were also considered as 'major'. These results reinforce the notion that not all CLL will end up being stereotyped but rather that a plateau for stereotypy exists at ~1/3 of the cohort. Subset #2 was the largest subset (n=572, 2.7%), while subset #1 (IGHV clan I (IGHV1,5,7 subgroups)/IGKV1(D)-39) was the most frequent subset within U-CLL (n=515, 2.4%) and subset #4 the most common M-CLL subset (n=192, 0.9%), hence displaying remarkable consistency regarding their frequency in all cohorts published since the pioneering studies. Altogether, Teiresias and AssignSubsets gave concordant results for previously identified major subsets, illustrating the validity of our approach. Satellite subsets were sought for individually for each major subset. In general, few satellite subsets were identified, most of which concerned U-CLL major subsets. That notwithstanding, notable cases of satellite subsets were exemplified by major subset #1 and its satellite subset #99 from which it differed only in VH CDR3 length (13 aminoacids in subset #1 versus 14 in subset #99); interestingly, both subsets displayed equally aggressive clinical course. Another example concerned subset #8 (IGHV4-39/IGKV1(D)-39, U-CLL), an aggressive subset with very high risk for Richter's transformation, that, except for a one-aminoacid difference in VH CDR3 length, was otherwise identical to satellite subset #215, also displaying clinical aggressiveness. Overall, our results confirm that major subsets can be robustly identified and are consistent in relative size, hence representing distinct disease subgroups amenable to compartmentalized research with the potential of overcoming the pronounced heterogeneity of CLL. Most major subsets display unique sequence motifs, however satellite subsets exist, especially within U-CLL. Considering ever-increasing evidence that major stereotyped subsets may represent distinct disease subgroups, the existence of satellite subsets reveals a novel aspect of repertoire restriction and has implications for refined molecular classification of CLL. Disclosures Shanafelt: Genentech: Research Funding; GlaxoSmithkKine: Research Funding; Celgene: Research Funding; Janssen: Research Funding; Pharmacyclics: Research Funding; Cephalon: Research Funding; Hospira: Research Funding. Gaidano:Roche: Consultancy, Honoraria, Speakers Bureau; Karyopharm: Consultancy, Honoraria; Morphosys: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau. Niemann:Janssen: Consultancy; Abbvie: Consultancy; Roche: Consultancy; Gilead: Consultancy. Langerak:F. Hofmann-LaRoche, Genentech: Research Funding; InVivoScribe Technologies: Patents & Royalties: Royalties are provided to European Network (EuroClonality). Jaeger:Roche: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Kater:Celgene: Research Funding; Gilead: Research Funding; Janssen: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Abbvie: Consultancy, Research Funding. Stilgenbauer:Amgen: Consultancy, Honoraria, Other: Travel grants, Research Funding; Gilead: Consultancy, Honoraria, Other: Travel grants , Research Funding; Genentech: Consultancy, Honoraria, Other: Travel grants , Research Funding; Celgene: Consultancy, Honoraria, Other: Travel grants , Research Funding; Boehringer Ingelheim: Consultancy, Honoraria, Other: Travel grants , Research Funding; Genzyme: Consultancy, Honoraria, Other: Travel grants , Research Funding; AbbVie: Consultancy, Honoraria, Other: Travel grants, Research Funding; GSK: Consultancy, Honoraria, Other: Travel grants , Research Funding; Janssen: Consultancy, Honoraria, Other: Travel grants , Research Funding; Mundipharma: Consultancy, Honoraria, Other: Travel grants , Research Funding; Novartis: Consultancy, Honoraria, Other: Travel grants , Research Funding; Pharmacyclics: Consultancy, Honoraria, Other: Travel grants , Research Funding; Hoffmann-La Roche: Consultancy, Honoraria, Other: Travel grants , Research Funding; Sanofi: Consultancy, Honoraria, Other: Travel grants , Research Funding. Hallek:Gilead: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; F. Hoffmann-LaRoche: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Mundipharma: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; AbbVie: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Janssen-Cilag: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Other: travel support, Research Funding, Speakers Bureau. Rosenquist:Gilead Sciences: Speakers Bureau. Ghia:Gilead: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Roche: Honoraria, Research Funding; Adaptive: Consultancy; Abbvie: Consultancy, Honoraria. Stamatopoulos:Novartis: Honoraria, Research Funding; Abbvie: Honoraria, Other: Travel expenses; Janssen: Honoraria, Other: Travel expenses, Research Funding; Gilead: Consultancy, Honoraria, Research Funding.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V128.22.4376.4376

Language: English

Publisher: American Society of Hematology

Publication Date: 2016

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 113, No. 11 ( 2009-03-12), p. 2488-2497

Abstract: Lymphomas are assumed to originate at different stages of lymphocyte development through chromosomal aberrations. Thus, different lymphomas resemble lymphocytes at distinct differentiation stages and show characteristic morphologic, genetic, and transcriptional features. Here, we have performed a microarray-based DNA methylation profiling of 83 mature aggressive B-cell non-Hodgkin lymphomas (maB-NHLs) characterized for their morphologic, genetic, and transcriptional features, including molecular Burkitt lymphomas and diffuse large B-cell lymphomas. Hierarchic clustering indicated that methylation patterns in maB-NHLs were not strictly associated with morphologic, genetic, or transcriptional features. By supervised analyses, we identified 56 genes de novo methylated in all lymphoma subtypes studied and 22 methylated in a lymphoma subtype–specific manner. Remarkably, the group of genes de novo methylated in all lymphoma subtypes was significantly enriched for polycomb targets in embryonic stem cells. De novo methylated genes in all maB-NHLs studied were expressed at low levels in lymphomas and normal hematopoietic tissues but not in nonhematopoietic tissues. These findings, especially the enrichment for polycomb targets in stem cells, indicate that maB-NHLs with different morphologic, genetic, and transcriptional background share a similar stem cell–like epigenetic pattern. This suggests that maB-NHLs originate from cells with stem cell features or that stemness was acquired during lymphomagenesis by epigenetic remodeling.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood-2008-04-152900

Language: English

Publisher: American Society of Hematology

Publication Date: 2009

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 2769-2769

Abstract: Background: Combined immuno-chemotherapy incorporating Rituximab with various chemotherapy regimens has resulted in increased response rates and prolonged progression-free and even overall survival in numerous trials. However, a constant relapse pattern has been observed even after such an optimized first line treatment. Methods: In a subgroup analysis of the GLSG trial for relapsed indolent lymphoma (R-FCM followed by Rituximab maintenance), response and long term results of patients with previous Rituximab containing treatment were compared with the Rituximab naive control group. Induction comprised of 4 courses of chemotherapy with Fludarabine, Cyclophosphamide and Mitoxantrone (FCM) plus Rituximab. Patients responding with a complete (CR) or partial remission (PR) were randomized for observation only versus Rituximab maintenance (4 applications at month 3 and 9). Results: 18 of 268 patients (arm A) with relapsed lymphoma had already previously received a R-containing regimen, the remainder 250 patients (arm B) were Rituximab naive. Overall response (arm A: 83 % vs. group B: 77%) and CR rate (arm A: 39% vs. arm B: 23%) were comparable in both subsets of study patients. Accordingly, progression-free survival after R-FCM was comparable in both subgroups of patients (median PFS in arm A: 15 months, arm B: 27 months) and overall survival as well. Especially, no disadvantage in the Rituximab pretreated patient group was detectable. 9 of the Rituximab pretreated patients responding to R-FCM induction therapy were randomized to maintenance treatment. After a median observation time of 20 months, 3 patients had relapsed and 6 patients remained in remission (3 of them for 〉 20 months) resulting in a similar PFS after rituximab maintenance as in patients who were Rituximab naive. Conclusion: This subgroup analysis strongly suggests that a Rituximab containing salvage therapy induction as well as maintenance is a highly effective treatment option even in patients who received Rituximab in first line therapy.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V108.11.2769.2769

Language: English

Publisher: American Society of Hematology

Publication Date: 2006

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood, American Society of Hematology, Vol. 118, No. 11 ( 2011-09-15), p. 3088-3095

Abstract: We examined 807 productive IGHV-IGHD-IGHJ gene rearrangements from mantle cell lymphoma (MCL) cases, by far the largest series to date. The IGHV gene repertoire was remarkably biased, with IGHV3-21, IGHV4-34, IGHV1-8, and IGHV3-23 accounting for 46.3% of the cohort. Eighty-four of 807 (10.4%) cases, mainly using the IGHV3-21 and IGHV4-34 genes, were found to bear stereotyped heavy complementarity-determining region 3 (VH CDR3) sequences and were placed in 38 clusters. Notably, the MCL stereotypes were distinct from those reported for chronic lymphocytic leukemia. Based on somatic hypermutation (SHM) status, 238/807 sequences (29.5%) carried IGHV genes with 100% germ line identity; the remainder (569/807; 70.5%) exhibited different SHM impact, ranging from minimal (in most cases) to pronounced. Shared replacement mutations across the IGHV gene were identified for certain subgroups, especially those using IGHV3-21, IGHV1-8, and IGHV3-23. Comparison with other entities, in particular CLL, revealed that several of these mutations were “MCL-biased.” In conclusion, MCL is characterized by a highly restricted immunoglobulin gene repertoire with stereotyped VH CDR3s and very precise SHM targeting, strongly implying a role for antigen-driven selection of the clonogenic progenitors. Hence, an antigen-driven origin of MCL could be envisaged, at least for subsets of cases.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood-2011-03-343434

Language: English

Publisher: American Society of Hematology

Publication Date: 2011

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7

In: Blood Advances, American Society of Hematology, Vol. 5, No. 13 ( 2021-07-13), p. 2707-2716

Abstract: The antibody-drug conjugate polatuzumab vedotin (pola) has recently been approved in combination with bendamustine and rituximab (pola-BR) for patients with refractory or relapsed (r/r) large B-cell lymphoma (LBCL). To investigate the efficacy of pola-BR in a real-world setting, we retrospectively analyzed 105 patients with LBCL who were treated in 26 German centers under the national compassionate use program. Fifty-four patients received pola as a salvage treatment and 51 patients were treated with pola with the intention to bridge to chimeric antigen receptor (CAR) T-cell therapy (n = 41) or allogeneic hematopoietic cell transplantation (n = 10). Notably, patients in the salvage and bridging cohort had received a median of 3 prior treatment lines. In the salvage cohort, the best overall response rate was 48.1%. The 6-month progression-free survival and overall survival (OS) was 27.7% and 49.6%, respectively. In the bridging cohort, 51.2% of patients could be successfully bridged with pola to the intended CAR T-cell therapy. The combination of pola bridging and successful CAR T-cell therapy resulted in a 6-month OS of 77.9% calculated from pola initiation. Pola vedotin-rituximab without a chemotherapy backbone demonstrated encouraging overall response rates up to 40%, highlighting both an appropriate alternative for patients unsuitable for chemotherapy and a new treatment option for bridging before leukapheresis in patients intended for CAR T-cell therapy. Furthermore, 7 of 12 patients with previous failure of CAR T-cell therapy responded to a pola-containing regimen. These findings suggest that pola may serve as effective salvage and bridging treatment of r/r LBCL patients.

Type of Medium: Online Resource

ISSN: 2473-9529 , 2473-9537

URL: Article

DOI: 10.1182/bloodadvances.2020004155

Language: English

Publisher: American Society of Hematology

Publication Date: 2021

detail.hit.zdb_id: 2876449-3

In: Blood, American Society of Hematology, Vol. 122, No. 21 ( 2013-11-15), p. 3367-3367

Abstract: High-dose cytarabine containing immuno-chemotherapy followed by autologous stem cell transplantation (ASCT) has been established as standard first-line treatment in younger mantle cell lymphoma (MCL) patients (ESMO guideline, Ann Oncol 2013). However, the role of total body irradiation (TBI) as conditioning regimen for ASCT has not been clarified so far. A retrospective EBMT survey of 418 MCL patients suggested a benefit of TBI with respect to the rate of relapse in patients who achieved a partial remission before ASCT (Rubio et al., ASH 2010). We combined the individual patient data of the Nordic MCL2 trial (Geisler et al., Blood 2008), the HOVON 45 trial (van’t Veer et al., BJH 2008, both without TBI), and the high-dose cytarabine containing study arm of the European MCL Younger trial (Hermine et al., ASH 2012, with TBI) to evaluate potential differences in long term outcome. Methods All trials included patients with advanced stage MCL up to 66 years and a central review of histology. Induction treatment of Nordic MCL2 consisted of 6 alternating courses of Maxi-CHOP or high-dose cytarabine (12g/m2 per cycle, 8g/m2 in patients 〉 60 years, total cumulative dose 24-36g/m2) combined with 4-6 cycles rituximab, in HOVON 45 three courses R-CHOP were followed by one cycle of high-dose cytarabine (16g/m2), and in MCL Younger patients received 6 alternating courses of R-CHOP or R-DHAP (4g/m2 cytarabine per cycle, total cumulative dose 12g/m2). Conditioning before ASCT consisted of BEAM or BEAC in Nordic MCL2, and BEAM in HOVON 45, whereas a TBI-containing regimen (TAM: 10 Gray TBI, 6g/m2 cytarabine, 140mg/m2 melphalan) was applied in MCL Younger. We compared baseline characteristics, progression free survival (PFS) overall survival (OS) after ASCT from the three patient cohorts with adjustment for MIPI (Hoster et al., Blood 2008) and quality of remission before ASCT. Results In Nordic MCL2, HOVON 45, and MCL Younger 145, 61, and 171 patients were transplanted in complete (CR) or partial (PR) remission (median age 57, 55, and 56 years, p=0.24). According to MIPI, 46%, 56%, and 67% were low risk, whereas 22%, 13%, and 11% were high risk patients (p=0.006). Five-year PFS after ASCT was 61%, 50%, and 78%, respectively (p 〈 0.001) after a median observation time of 6.6, 6.5, and 4.2 years). After adjustment for MIPI score and quality of response (CR/unconfirmed CR vs. PR) before ASCT, the hazard ratio for PFS after ASCT of MCL Younger vs. Nordic MCL2 was 0.75 (p=0.17). Among the patients with CR or unconfirmed CR before ASCT, the adjusted hazard ratio was 0.91 (p=0.76) in comparison to 0.66 (p=0.17) among the PR patients. On the other hand, the hazard ratio of MCL Younger in comparison to HOVON 45 was 0.45 (p=0.001) after adjustment for MIPI score. OS after ASCT was not different between the three cohorts with 5-year OS rates of 75%, 71%, and 80%, respectively (p=0.61). Conclusion The longer PFS after ASCT of MCL Younger compared to HOVON 45 patients may be due to the different time schedule of cytarabine during induction or to a higher efficacy of TBI vs. BEAM, as the total chemotherapy doses were comparable and we adjusted for MIPI. We could not see an improved PFS after ASCT of MCL Younger compared to Nordic MCL2 patients transplanted in CR or unconfirmed CR and, after adjustment for the different risk profiles, this was also not clearly seen for patients transplanted in PR. Taking into account the substantially higher cytarabine dose in Nordic MCL2 during induction one might speculate that this fact at least partially compensated for a higher efficacy of TBI. Multivariable analyses incorporating additional prognostic factors (Ki-67 and MRD) will help to clarify the impact of the individual parts of the current multimodal approach in younger MCL patients. On behalf of the European Mantle Cell Lymphoma Network Disclosures: No relevant conflicts of interest to declare.

Type of Medium: Online Resource

ISSN: 0006-4971 , 1528-0020

URL: Article

DOI: 10.1182/blood.V122.21.3367.3367

Language: English

Publisher: American Society of Hematology

Publication Date: 2013

detail.hit.zdb_id: 1468538-3

detail.hit.zdb_id: 80069-7