Targeted genotyping of circulating tumor DNA for classical Hodgkin lymphoma monitoring: a prospective study.

The relevance of circulating tumor DNA (ctDNA) analysis as a liquid biopsy and minimal residual disease tool in the management of classical Hodgkin Lymphoma (cHL) patients was demonstrated in retrospective settings and remains to be confirmed in a prospective setting. We developed a targeted Next-Generation sequencing (NGS) panel for fast analysis (AmpliSeq technology) of nine commonly mutated genes in biopies and ctDNA of cHL patients. We then conducted a prospective trial to assess ctDNA follow up at diagnosis and after 2 cycles of chemotherapy (C2). Sixty cHL patients treated by first line conventional chemotherapy (BEACOPPescalated [21.3%], ABVD/ABVD-like [73.5%] and other regimens [5.2%, for elderly patients] were assessed in this non-interventional study. Median age of the patients was 33.5 years (range 20-86). Variants were identified in 42 (70%) patients. Mutations of NFKBIE, TNFAIP3, STAT6, PTPN1, B2M, XPO1, ITPKB, GNA13 and SOCS1 were found in 13.3%, 31.7%, 23.3%, 5%, 33.3%, 10%, 23.3%, 13.3% and 50% of patients, respectively. ctDNA concentration and genotype are correlated with clinical characteristics and presentation. Regarding early therapeutic response, 45 patients (83%, NA=6) had a negative positron emission tomography (PET) after C2 (Deauville Score 1-3). Mean of DeltaSUVmax after C2 was -78.8%. We analyzed ctDNA after C2 for 54 patients (90%). ctDNA became rapidly undetectable in all cases after C2. Variant detection in ctDNA is suitable to depict the genetic features of cHL at diagnosis and may help to assess early treatment response, in association with PET. Clinical Trial reference: NCT02815137.

A recurrent clonally distinct Burkitt lymphoma case highlights genetic key events contributing to oncogenesis.

Burkitt lymphoma (BL) is characterized by a translocation of the MYC oncogene that leads to the upregulation of MYC expression, cell growth and proliferation. It is well-established that MYC translocation is not a sufficient genetic event to cause BL. Next-generation sequencing has recently provided a comprehensive analysis of the landscape of additional genetic events that contribute to BL lymphomagenesis. Refractory BL or relapsing BL are almost always incurable as a result of the selection of a highly chemoresistant clonally related cell population. Conversely, a few BL recurrence cases arising from clonally distinct tumors have been reported and were associated with a favorable outcome similar to that reported for first-line treatment. Here, we used an unusual case of recurrent but clonally distinct EBV+ BL to highlight the key genetic events that drive BL lymphomagenesis. By whole exome sequencing, we established that ID3 gene was targeted by distinct mutations in the two clonally unrelated diseases, highlighting the crucial role of this gene during lymphomagenesis. We also detected a heterozygous E1021K PIK3CD mutation, thus increasing the spectrum of somatic mutations altering the PI3K signaling pathway in BL. Interestingly, this mutation is known to be associated with activated phosphoinositide 3-kinase delta syndrome (APDS). Finally, we also identified an inherited heterozygous truncating c.5791CT FANCM mutation that may contribute to the unusual recurrence of BL.

Oncogenic events rather than antigen selection pressure may be the main driving forces for relapse in diffuse large B-cell lymphomas.

Little is known on the phylogenetic relationship between diagnostic and relapse clones of diffuse large B-cell lymphoma (DLBCL). We applied high throughput sequencing (HTS) of the VDJ locus of Immunoglobulin heavy chain (IGHV) on 14 DLBCL patients with serial samples, including tumor biopsies and/or peripheral blood mononuclear cells (PBMC). Phylogenetic data were consolidated with targeted sequencing and cytogenetics. Phylogeny clearly showed that DLBCL relapse could occur according either an early or a late divergent mode. These two modes of divergence were independent from the elapsed time between diagnosis and relapse. We found no significant features for antigen selection pressure in complementary determining region both at diagnosis and relapse for 9/12 pairs and a conserved negative selection pressure for the three remaining cases. Targeted HTS and conventional cytogenetics revealed a branched vs. linear evolution for 5/5 IGHV early divergent cases, but unexpected such "oncogenetic" branched evolution could be found in at least 2/7 IGHV late divergent cases. Thus, if BCR signaling is mandatory for DLBCL emergence, oncogenetic events under chemotherapy selection pressure may be the main driving forces at relapse. Finally, circulating subclones with divergent IGHV somatic hypermutations patterns from initial biopsy could be detected in PBMC at diagnosis for 4/6 patients and, for two of them, at least one was similar to the ones found at relapse. This study highlights that oncogenetic intraclonal diversity of DLBCL should be evaluated beyond the scope a single biopsy and represents a rationale for future investigations using peripheral blood for lymphoid malignancies genotyping. Am. J. Hematol. 92:68-76, 2017. © 2016 Wiley Periodicals, Inc.

Frequent ASXL2 mutations in acute myeloid leukemia patients with t(8;21)/RUNX1-RUNX1T1 chromosomal translocations.

Acute myeloid leukemia (AML) with t(8;21) (q22;q22) is considered to have favorable risk; however, nearly half of t(8;21) patients are not cured, and recent studies have highlighted remarkable genetic heterogeneity in this subset of AML. Here we identify somatic mutations in additional sex combs-like 2 (ASXL2) in 22.7% (25/110) of patients with t(8;21), but not in patients with inv(16)/t(16;16) (0/60) or RUNX1-mutated AML (0/26). ASXL2 mutations were similarly frequent in adults and children t(8;21) and were mutually exclusive with ASXL1 mutations. Although overall survival was similar between ASXL1 and ASXL2 mutant t(8;21) AML patients and their wild-type counterparts, patients with ASXL1 or ASXL2 mutations had a cumulative incidence of relapse of 54.6% and 36.0%, respectively, compared with 25% in ASXL1/2 wild-type counterparts (P = .226). These results identify a high-frequency mutation in t(8;21) AML and identify the need for future studies to investigate the clinical and biological relevance of ASXL2 mutations in this unique subset of AML.

Targetable activating mutations are very frequent in GCB and ABC diffuse large B-cell lymphoma.

Diffuse large B cell lymphoma (DLBCL) is an aggressive and heterogeneous malignancy that can be divided in two major subgroups, germinal center B-cell-like (GCB) and activated B-cell-like (ABC). Activating mutations of genes involved in the BCR and NF-κB pathways (CD79A, CD79B, MYD88, and CARD11) or in epigenetic regulation (EZH2) have been recently reported, preferentially in one of the two DLBCL subtypes. We analyzed the mutational status of these five recurrently mutated genes in a cohort of 161 untreated de novo DLBCL. Overall, 93 mutations were detected, in 61 (38%) of the patients. The L265P MYD88 mutation was the most frequent MYD88 variant (n = 18), observed exclusively in the ABC subtype. CD79A/CD79B ITAM domains were targeted in ABC DLBCL (12/77; 16%), whereas CARD11 mutations were equally distributed in the two subtypes. The EZH2 Y641 substitution was found almost exclusively in the GCB subgroup (15/62; 24%). Twenty cases (12%) displayed two activating mutations, including the most frequent CD79/MYD88 variants combination (n = 8) which is observed exclusively in the ABC subtype. When considering only ABC DLBCL patients treated by rituximab plus chemotherapy, the presence of an activating NF-κB mutation was associated with an unfavorable outcome (3-years OS 26% for mutated cases versus 67% for the cases without mutations, P = 0.0337). Our study demonstrates that activating and targetable mutations are observed at a very high frequency in DLBCL at the time of diagnosis, indicating that sequencing of a limited number of genes could help tailor an optimal treatment strategy in DLBCL.

Complete hematologic response after belinostat treatment and allogeneic stem cell transplantation for multiple relapsed/refractory angioimmunoblastic T-cell lymphoma: A case report.

Key Clinical Message: This case report highlights the potential of belinostat for the treatment of relapsed/refractory peripheral T-cell lymphomas, for which effective therapies are still scarce. Abstract: Peripheral T-cell lymphomas have an aggressive disease course associated with poor outcomes. We report a young patient with highly pretreated relapsed/refractory nodal follicular helper T-cell lymphoma (angioimmunoblastic-type [nTFHL-AI]), who successfully received an allogeneic stem cell transplantation following belinostat therapy. The complete hematologic response achieved has lasted more than 2 years.

Germ-line GATA2 p.THR354MET mutation in familial myelodysplastic syndrome with acquired monosomy 7 and ASXL1 mutation demonstrating rapid onset and poor survival.

While most myelodysplastic syndrome/acute myeloid leukemia cases are sporadic, rare familial cases occur and provide some insight into leukemogenesis. The most clearly defined familial cases result from inherited mutations in RUNX1 or CEBPA. Recently, novel germline mutations in GATA2 have been reported. We, therefore, investigated individuals from families with one or more first-degree relatives with myelodysplastic syndrome/acute myeloid leukemia with wild-type RUNX1 and CEBPA, for GATA2 mutations. Screening for other recurrent mutations was also performed. A GATA2 p.Thr354Met mutation was observed in a pedigree in which 2 first-degree cousins developed high-risk myelodys-plastic syndrome with monosomy 7. They were also observed to have acquired identical somatic ASXL1 mutations and both died despite stem cell transplantation. These findings confirm that germline GATA2 mutations predispose to familial myelodysplastic syndrome/acute myeloid leukemia, and that monosomy 7 and ASXL1 mutations may be recurrent secondary genetic abnormalities triggering overt malignancy in these families.

Utility of assessing CD3+ cell chimerism within the first months after allogeneic hematopoietic stem-cell transplantation for acute myeloid leukemia.

After allogeneic hematopoietic stem-cell transplantation (alloHSCT), the chimerism assay is used to monitor cell engraftment and quantify the respective proportions of donor/recipient cells in blood or bone-marrow samples. Here, we aimed to better assess the utility of determining CD3+ cell chimerism within the first 6 months post alloHSCT. One hundred and thirty five patients diagnosed with acute myeloid leukemia were enrolled in this study. We observed significantly lower overall survival and relapse free survival for patients without full donor chimerism (<95%, <98%, <99%) in whole blood at Day 30, as well as at Day 90 after alloHSCT, than for patients with full donor chimerism. This outcome was not observed when assessing selected CD3+ cells. However, at Day 90, patients with discordant whole blood versus selected CD3+ cell chimerism showed both significantly lower overall survival and relapse free survival, giving an interest to assess selected cells chimerism.

5' Rapid amplification of cDNA ends (5'RACE): A simpler method to analyze immunoglobulin genes and discover the value of the light chain in chronic lymphocytic leukemia.

The mutational status of the variable region of the immunoglobulin heavy chain gene (IGHV) is a very important biomarker for chronic lymphocytic leukemia (CLL) patients. However, the routine detection of IGHV mutational status is time-consuming and costly. Therefore, we performed 5' Rapid amplification of cDNA ends (5' RACE) in 81 CLL patients who previously underwent detection using Biomed-2. The agreement rate of these two methods was 93.8 %. Regarding the discordant cases, 5' RACE was more sensitive to identify unproductive and multiple rearrangements. Furthermore, 5' RACE can also be used to simultaneously sequence light chains. In most CLL cases, the mutational statuses of heavy and light chains are concordant, except in IGLV3-21. Most IGLV3-21 (24/25) rearrangement shared a similar LCDR3 (QVWDSSSDHPWV) and harbored a single point mutation, namely, IGLV3-21R110. Compared to mutated-CLL non IGLV3-2R110, IGLV3-21R110-CLL exhibited a shorter overall survival (OS) and time to first treatment (TTFT) (p = 0.05, p < 0.0001, respectively) even though 75 % (18/24) of these patients expressed mutated heavy chains. Altogether, IGLV3-21R110 defines a CLL subgroup with specific biological features and an unfavorable prognosis independent of the IGHV mutational status and emphasizes the important value of the light chain. This study is the first to use 5' RACE to detect the mutational status of IGH in CLL. Here, 5' RACE was a reliable and effective method to test the mutational status of heavy and light chains. In addition, 5' RACE can be combined with other assays in the NGS workflow to obtain more detailed insight into subclonal architecture and intraclonal diversity.

Circulating tumor DNA in primary mediastinal large B-cell lymphoma versus classical Hodgkin lymphoma: a retrospective study.

Few data exist concerning circulating tumor DNA (ctDNA) relevance in primary mediastinal B-cell lymphoma (PMBL). To explore this topic, we applied a 9-gene next-generation sequencing pipeline to samples from forty-four PMBL patients (median age 36.5 years). The primary endpoint was a similarity between paired biopsy/plasma mutational profiles. We detected at least one variant in 32 plasma samples (80%). The similarity between the biopsy and ctDNA genetic profiles for the 30 patients with paired mutated biopsy/plasma samples was greater than or equal to 80% in 19 patients (63.3%). We then compared PMBL ctDNA features with those of a cohort of Hodgkin lymphoma patients (n = 60). The top three mutated genes were SOCS1, TNFAIP3, and B2M in both lymphoma types. PMBL displayed more alterations in TNFAIP3 (71.9% vs. 46.3%, p = 0.029) and GNA13 (46.9% vs. 17.1%, p = 0.013) than cHL. Our 9-gene set may delineate tumor genotypes using ctDNA samples from both lymphoma types.

Cardiovascular outcomes of patients treated for non-Hodgkin lymphoma with first-line doxorubicin-based chemotherapy.

We conducted a single-center retrospective study to assess cardiovascular (CV) toxicity and treatment discontinuation for CV toxicity in diffuse large B-cell lymphoma (DLBCL) or follicular lymphoma (FL) patients treated with immunochemotherapy (R-CHOP-like). Between 2006 and 2017, 433 patients were included (DLBCL: n = 345, FL: n = 88). The median age was 63 years (50-73). We defined three types of CV toxicity: early-onset cardiovascular toxicity (the event occurred within 6 months following treatment start); subacute toxicity (the event occurred between 6 months and 1 year after treatment start) and late toxicity (the event occurred 1 year or more after treatment start). Forty-eight (11.1%) patients experienced at least one anthracycline-related CV event. Seven patients experienced treatment discontinuation due to CV toxicity. Early-onset and subacute cardiac events were primarily acute heart failure (34.3%) and atrial fibrillation (28.6%). History of ischemic heart disease (p = 0.02) and valvular heart disease (p = 0.03) were associated with a higher risk of anthracycline-related CV event occurrence.

Successful treatment of T/myeloid mixed-phenotype acute leukemia with the translocation (10;11)(p13;q14) PICALM/AF10 with 3 + 7 myeloid standard treatment: A case report.

The translocation PICALM/AF10 is described in multilineage diseases. We report a patient with PICALM/AF10 T/myeloid mixed-phenotype acute leukemia who achieved durable complete remission after AML-like treatment suggesting a myeloid origin.

Circulating PIK3CA mutation detection at diagnosis in non-metastatic inflammatory breast cancer patients.

Inflammatory breast cancer (IBC) is an aggressive BC subtype with poor outcomes. A targetable somatic PIK3CA mutation is reported in 30% of IBC, allowing for treatment by PI3Kα-specific inhibitors, such as alpelisib. The aim of this study was to evaluate the detection rate of circulating PIK3CA mutation in locally-advanced IBC (LAIBC) patients harbouring a PIK3CA mutation on initial biopsy. This monocentric retrospective study was based on available stored plasma samples and tumour biopsies at diagnosis from all LAIBC patients treated with neo-adjuvant chemotherapy (NCT) between 2008 and 2018 at the Centre Henri Becquerel. PIK3CA mutations (E542K, E545K, H1047R/L) were assessed by droplet digital PCR (ddPCR) in plasma samples and tumoral tissue at diagnosis. A total of 55 patients were included. Overall, 14/55 patients (25%) had a PIK3CA mutation identified on baseline biopsy (H1047R = 8; H1047L = 3; E545K = 2; E542K = 1). Among them, 11 (79%) patients had enough DNA for circulating DNA analyses, and corresponding circulating PIK3CA mutations were found in 6/11 (55%). Among the 41 patients without PIK3CA mutations on biopsy, 32 (78%) had enough DNA for circulating DNA analysis, and no circulating PIK3CA mutation was identified. Our results revealed no prognostic or predictive value of PIK3CA mutations at the diagnosis of non-metastatic IBC but highlighted the prognostic value of the cfDNA rate at diagnosis. Our study showed that a corresponding circulating PIK3CA mutation was identified in 55% of LAIBC patients with PIK3CA-mutated tumours, while no circulating mutation was found among patients with PI3KCA wild-type tumours.

Multiple cutaneous ulcers revealing a primary cutaneous Epstein-Barr virus-positive diffuse large B-cell lymphoma.

Primary cutaneous EBV-positive diffuse large B-cell lymphoma is an exceptional and aggressive neoplasia with a poorer prognosis than other cutaneous lymphoma. Our observation points out the rarity of the presentation and the dismal clinical course.

[Recommendations from the French CML Study Group (Fi-LMC) for BCR-ABL1 kinase domain mutation analysis in chronic myeloid leukemia]. / Recommandations du France Intergroupe des leucémies myéloïdes chroniques (Fi-LMC) pour l'examen des mutations du domaine kinase de BCR-ABL1 dans la leucémie myéloïde chronique.

In the context of chronic myeloid leukemia (CML) resistant to tyrosine kinase inhibitors (TKIs), BCR-ABL1 tyrosine kinase domain (TKD) mutations still remain the sole biological marker that directly condition therapeutic decision. These recommendations aim at updating the use of BCR-ABL1 mutation testing with respect to new available therapeutic options and at repositioning different testing methods at the era of next generation sequencing (NGS). They have been written by a panel of experts from the French Study Group on CML (Fi-LMC), after a critical review of relevant publications. TKD mutation testing is recommended in case of treatment failure but not in case of optimal response. For patients in warning situation, mutation testing must be discussed depending on the type of TKI used, lasting of the treatment, kinetic evolution of BCR-ABL1 transcripts along time and necessity for switching treatment. The kind and the frequency of TKD mutations occasioning resistance mainly depend on the TKI in use and disease phase. Because of its better sensitivity, NGS methods are recommended for mutation testing rather than Sanger's. Facing a given TKD mutation, therapeutic decision should be taken based on in vitro sensitivity and clinical efficacy data. Identification by sequencing of a TKD mutation known to induce resistance must lead to a therapeutic change. The clinical value of testing methods more sensitive than NGS remains to be assessed.

[Accreditation strategy for rare somatic molecular abnormalities detected or quantified by polymerase chain reaction: GBMHM recommendations]. / Stratégie d'accréditation des anomalies moléculaires somatiques rares détectées ou quantifiées par polymerase chain reaction : recommandations du GBMHM.

In 2020, accreditation of molecular tests according to ISO 15189 is a requirement for all French medical laboratories. For many years, the GBMHM group (French Group of Molecular Biologists in Hematology) supports this approach through organization of external quality evaluation campaigns, and by publishing recommendations that have allowed the accreditation of the most frequent molecular tests for most laboratories. However, some molecular abnormalities concerns very few patients (and sometimes a single patient), and therefore cannot be evaluated in the same way, because of the lack of external quality controls or inter-laboratory comparisons. In order to allow the accreditation of these rare analyzes, the GBMHM proposes recommendations, based on the fact that analyzes using the same methodology than those already accredited by an extensive validation process, may be accredited without the need for full analytical validation. In particular, assays based on quantitative PCR or endpoint PCR may be accredited after verification of primer specificity, repeatability and/or reproducibility, and the determination of detection or linearity limits. These recommendations, by defining the validation approach for rare molecular abnormalities, make it possible to extend the requirement of accreditation for rare tests, to provide the best patient care.