Defining signatures of peripheral T-cell lymphoma with a targeted 20-marker gene expression profiling assay.

Peripheral T-cell lymphoma comprises a heterogeneous group of mature non-Hodgkin lymphomas. Their diagnosis is challenging, with up to 30% of cases remaining unclassifiable and referred to as "not otherwise specified". We developed a reverse transcriptase-multiplex ligation-dependent probe amplification gene expression profiling assay to differentiate the main T-cell lymphoma entities and to study the heterogeneity of the "not specified" category. The test evaluates the expression of 20 genes, including 17 markers relevant to T-cell immunology and lymphoma biopathology, one Epstein-Barr virus-related transcript, and variants of RHOA (G17V) and IDH2 (R172K/T). By unsupervised hierarchical clustering, our assay accurately identified 21 of 21 ALK-positive anaplastic large cell lymphomas, 16 of 16 extranodal natural killer (NK)/T-cell lymphomas, 6 of 6 hepatosplenic T-cell lymphomas, and 13 of 13 adult T-cell leukemia/lymphomas. ALK-negative anaplastic lymphomas (n=34) segregated into one cytotoxic cluster (n=10) and one non-cytotoxic cluster expressing Th2 markers (n=24) and enriched in DUSP22-rearranged cases. The 63 T <sub>FH</sub> -derived lymphomas divided into two subgroups according to a predominant T <sub>FH</sub> (n=50) or an enrichment in Th2 (n=13) signatures. We next developed a support vector machine predictor which attributed a molecular class to 27 of 77 not specified T-cell lymphomas: 17 T <sub>FH</sub> , five cytotoxic ALK-negative anaplastic and five NK/T-cell lymphomas. Among the remaining cases, we identified two cell-of-origin subgroups corresponding to cytotoxic/Th1 (n=19) and Th2 (n=24) signatures. A reproducibility test on 40 cases yielded a 90% concordance between three independent laboratories. This study demonstrates the applicability of a simple gene expression assay for the classification of peripheral T-cell lymphomas. Its applicability to routinely-fixed samples makes it an attractive adjunct in diagnostic practice

Prise en charge nutritionnelle des patients atteints de cancer de la tête et du cou traité par irradiation

International audienceRadiotherapy and chemotherapy are standard treatment of head and neck cancer alone or associated to surgical treatment. Early (during treatment or the following weeks) and late side effects contribute to malnutrition in this population at risk. In this context, nutritional support adapted by dietary monitoring and enteral nutrition (nasogastric tube or gastrostomy) are often necessary. The early identification of the patients with high malnutrition risk and requiring enteral nutrition is necessary to improve the tolerance and efficacy of treatment

GENE EXPRESSION PROFILING USING a RTMLPA ASSAY ALLOWS FOR AN ACCURATE CLASSIFICATION OF PERIPHERAL T-CELL LYMPHOMA AND HIGHLIGHTS NOVEL SUBGROUPS WITHIN PTCLS-NOS

International audienceMore than 20 Peripheral T‐cell lymphoma (PTCL) entities are recognized in the WHO classification. Their prognosis is usually very poor and their diagnosis is often challenging for pathologists. Up to 30% of cases thus remain not classifiable (PTCL Not Otherwise Specified, NOS) and there is an important need for alternative diagnostic strategies. Here, we developed a parsimonious GEP assay applicable to a routine diagnostic workflow to differentiate the main PTCL entities and characterize the heterogeneity of PTCL‐NOS.A Reverse Transcriptase‐Multiplex Ligation dependant Probe Amplification (RT‐MLPA) assay was designed to evaluate the expression of 20 markers. It simultaneously addresses the expression of 18 genes routinely tested by immunohistochemistry (IHC) or selected from GEP studies. It also assesses the EBV infection status (EBER1) and the presence of RHOAG17 V and IDH2R172K/T mutations.Unsupervised hierarchical clustering of RT‐MLPA data from 102 control cases validated the capacity of our assay to identify the main PTCL entities. All Angioimmunoblastic T‐cell lymphomas (AITL; n = 29), Anaplastic large T‐cell lymphomas (ALCL; n = 23) ALK+, NK/T‐cell lymphomas (NKTCL; n = 16), Hepatosplenic T‐cell lymphomas (HSTL; n = 6) and Adult T‐cell Leukemia/Lymphomas (ATLL; n = 12) were correctly identified. AITLs classified according to the expression of Tfh markers (CXCL13, CXCR5, ICOS, BCL6) and RHOA mutations (n = 18); NKTCLs according to EBER1, GZMB and Th1 markers (TBX21, IFNγ); HSTLs to CD56, GATA3, TBX21 and BCL6; ALCL ALK+ according to CD30, ALK and cytotoxic markers (PRF, GZMB); ATLLs to ICOSand Th2 markers (GATA3, CCR4). Interestingly, ALCL ALK‐ cases (n = 16) divided into two CD30+ subgroups: one associated with expressions of cytotoxic markers which clustered with ALCL ALK+ cases (n = 10), and a second which did not expressed PRF and GZMB but the two GATA3 and CCR4 Th2 markers (n = 6). We next developed a support vector machine based predictor combined with a centroid categorization. Applied to a series of 125 PTCL‐NOS, this algorithm reclassified 36 Tfh (AITL‐like), 6 CD30/Th2, 6 ALCL ALK‐ like, 3 HSTL‐like and 5 NKTCL‐like PTCLs. After exclusion of these cases, unsupervised clustering analysis identified 17 cytotoxic/Th1 (GZMB, PRF,TBX21, IFNγ) cases, 14 Th2 (GATA3, CCR4) cases and 14 TH2/Tfh (GATA3, CCR4, CXCR5, ICOS) cases. Finally, 24 cases (10.5% of the cohort) did not show any recognizable signature.This study demonstrates the applicability of a robust RT‐MLPA classifier for the classification of PTCLs. Its simplicity and its applicability on FFPE samples makes it an attractive alternative to high throughout GEP approaches. In combination with conventional pathological evaluation and IHC, it may participate to improve the classification of PTCLs and the management of these aggressive tumors.Keywords: gene expression profile (GEP); peripheral T‐cell lymphomas (PTCL)

Detection of Gene Fusion Transcripts in Peripheral T-Cell Lymphoma Using a Multiplexed Targeted Sequencing Assay.

The genetic basis of peripheral T-cell lymphoma (PTCL) is complex and encompasses several recurrent fusion transcripts discovered over the past years by means of massive parallel sequencing. However, there is currently no affordable and rapid technology for their simultaneous detection in clinical samples. Herein, we developed a multiplex ligation-dependent RT-PCR-based assay, followed by high-throughput sequencing, to detect 33 known PTCL-associated fusion transcripts. Anaplastic lymphoma kinase (ALK) fusion transcripts were detected in 15 of 16 ALK-positive anaplastic large-cell lymphomas. The latter case was further characterized by a novel SATB1_ALK fusion transcript. Among 239 other PTCLs, representative of nine entities, non-ALK fusion transcripts were detected in 24 samples, mostly of follicular helper T-cell (TFH) derivation. The most frequent non-ALK fusion transcript was ICOS_CD28 in nine TFH-PTCLs, one PTCL not otherwise specified, and one adult T-cell leukemia/lymphoma, followed by VAV1 rearrangements with multiple partners (STAP2, THAP4, MYO1F, and CD28) in five samples (three PTCL not otherwise specified and two TFH-PTCLs). The other rearrangements were CTLA4_CD28 (one TFH-PTCL), ITK_SYK (two TFH-PTCLs), ITK_FER (one TFH-PTCL), IKZF2_ERBB4 (one TFH-PTCL and one adult T-cell leukemia/lymphoma), and TP63_TBL1XR1 (one ALK-negative anaplastic large-cell lymphoma). All fusions detected by our assay were validated by conventional RT-PCR and Sanger sequencing in 30 samples with adequate material. The simplicity and robustness of this targeted multiplex assay make it an attractive tool for the characterization of these heterogeneous diseases

ANOCEF Consensus Guideline on Target Volume Delineation for Meningiomas Radiotherapy

Purpose/Objective(s)Meningiomas are the most common primary intracranial tumor. They are developed at the expense of the dura, with an overall incidence which has increased over the past decade. To date, there is no published specific guideline about meningiomas target volume. No prospective study has defined a consensus for delineation in meningiomas’ radiotherapy. Therefore, target volume definition is mainly based on retrospective studies, with a heterogeneous population of patients. The aim of this paper is to describe delineation guidelines for meningiomas’ radiotherapy as an adjuvant or definitive treatment with Intensity Modulated Radiation Therapy (IMRT) and stereotactic radiation therapy (SRT) techniques.Materials/MethodsThis guideline is based on a consensus endorsed by a global multidisciplinary group of brain tumor experts’ member of the ANOCEF (French neuro-oncology association). A two round modified Delphi consensus was achieved, and the consensus was adopted by the RAND/UCLA method. The third round was carried out in videoconference, in order to allow experts to debate and argue on remaining uncertain proposals.ResultsTwenty experts from 17 radiotherapy center participated. After 3 rounds, all the proposals resulted in a consensus. The ANOCEF guideline committee proposed to perform an unenhanced planning CT scan, merged with a post-contrast MRI obtained at the time of radiotherapy and preoperative MRI in case of adjuvant treatment. GTV is defined by T1 contrast-enhancing lesion, thickened meninges, and directly invaded bone. For IMRT, the CTV include: Grade I: No margin around the GTV. Grade II: Margin of 5mm to expand GTV in normal brain tissue, hyperostosis, along the unthickened meninges and venous sinuses if the GTV is coming into contact. Grade III: Margin of 10mm to expand GTV in normal brain tissue, hyperostosis, along the unthickened meninges, and optic or cranial nerves in contact with GTV. In case of bone invasion, a margin of 5 or 10mm in the healthy bone around the GTV is recommended, for grade II or III respectively. Otherwise, it is considered as an anatomical barrier and does not need to be included in the target volume. In case of post-operative radiotherapy, no additional margin is required for CTV for grade I around tumor bed. A 5 and 10mm margin is required for grade II and III. The cranial flap should only be included in the CTV only over 5 or 10mm for grades II or III, in case of initially invaded bone. The drill holes and osteotomy areas should be included if they come into contact with target volume. SRT is not recommended for grades II and III, excluding relapse situation. CTV corresponds to GTV without additional margin.ConclusionThe current consensus provides a detailed delineation guideline for meningioma, suggesting smaller margins than the major studies published to date