The molecular hallmarks of primary and secondary vitreoretinal lymphoma

Vitreoretinal lymphoma (VRL) is a rare subtype of diffuse large B-cell lymphoma (DLBCL) considered a variant of primary central nervous system lymphoma (PCNSL). Diagnosis of VRL requires examination of vitreous fluid, but cytologic differentiation from uveitis remains difficult. Due to its rarity and difficulty in obtaining diagnostic material, little is known about the genetic profile of VRL. The aim of our study was to investigate the mutational profile of a large series of primary and secondary VRL. Targeted next generation sequencing using a custom panel containing the most frequent mutations in PCNSL was performed on 34 vitrectomy samples of 31 patients with VRL and negative controls with uveitis. In a subset of cases, genome-wide copy number alterations (CNA) were assessed using the Oncoscan platform. Mutations in MYD88 (74%), PIM1 (71%), CD79B (55%), IGLL5 (52%), TBL1XR1 (48%), ETV6 (45%) and 9p21/CDKN2A deletions (85%) were the most common alterations, with similar frequencies in primary (15), synchronous (3) or secondary (13) VRL. This mutational spectrum is similar to MYD88mut/CD79Bmut (MCD or cluster 5) DLBCL with activation of Toll-like and B-cell receptor pathways and CDKN2A loss, confirming their close relationship. Oncoscan analysis demonstrated a high number of CNAs (mean 18.6/case). Negative controls lacked mutations or CNAs. Using cell free DNA of vitreous fluid supernatant, mutations present in cellular DNA were reliably detected in all examined cases. Mutational analysis is a highly sensitive and specific tool for the diagnosis of VRL and can also be applied successfully to cell free DNA derived from the vitreous.Copyright © 2021 American Society of Hematology

Cryobiopsy increases the EGFR detection rate in non-small cell lung cancer

Objectives: Detection of activating epidermal growth factor receptor (EGFR) mutation is crucial for individualized treatment of advanced non-small-cell lung cancer (NSCLC). However little is known about how biopsy technique affects the detection rate of EGFR mutations. This retrospective, single center study evaluated the detection rate of EGFR mutations in tissue obtained by bronchoscopic cryobiopsy and compared this to other standard tissue sampling techniques. Materials and methods: We retrospectively analyzed 414 patients with histologically confirmed NSCLC and known EGFR mutation status between 3/2008-7/2014. Tumor specimens obtained by tissue preserving bronchoscopic cryobiopsy were compared to those obtained by other techniques. Results and conclusion: Analysis of bronchoscopic cryobiopsy tissue detected 29 activating EGFR mutations in 27 (21.6 ) out of 125 patients, while analysis of tissue obtained by non-cryobiopsy techniques (bronchoscopic forceps biopsies, fine needle aspiration, imaging guided transthoracical and surgical procedures) detected 42 EGFR mutations in 40 (13.8 ) out of 298 patients (p < 0.05). Cryobiopsy increased detection rate of EGFR mutations in central tumors compared with forceps biopsy (19.6 versus 6.5 , p < 0.05), while an insignificant trend was detected also for peripheral tumors (33.3 versus 26.9 ). Bronchosopic cryobiopsy increases the detection rate of activating EGFR mutations in NSCLC in comparison to other tissue sampling techniques. This will help to optimize individualized treatment of patients with advanced tumors. Because of the retrospective nature of this analysis, a prospective trial is mandatory for final assessment. © 2020 The Author(s

Influence of Biopsy Technique on Molecular Genetic Tumor Characterization in Non-Small Cell Lung Cancer—The Prospective, Randomized, Single-Blinded, Multicenter PROFILER Study Protocol

The detection of molecular alterations is crucial for the individualized treatment of advanced non-small cell lung cancer (NSCLC). Missing targetable alterations may have a major impact on patient’s progression free and overall survival. Although laboratory testing for molecular alterations has continued to improve; little is known about how biopsy technique affects the detection rate of different mutations. In the retrospective study detection rate of epidermal growth factor (EGFR) mutations in tissue extracted by bronchoscopic cryobiopsy (CB was significantly higher compared to other standard biopsy techniques. This prospective, randomized, multicenter, single blinded study evaluates the accuracy of molecular genetic characterization of NSCLC for different cell sampling techniques. Key inclusion criteria are suspected lung cancer or the suspected relapse of known NSCLC that is bronchoscopically visible. Patients will be randomized, either to have a CB or a bronchoscopic forceps biopsy (FB). If indicated, a transbronchial needle aspiration (TBNA) of suspect lymph nodes will be performed. Blood liquid biopsy will be taken before tissue biopsy. The primary endpoint is the detection rate of molecular genetic alterations in NSCLC, using CB and FB. Secondary endpoints are differences in the combined detection of molecular genetic alterations between FB and CB, TBNA and liquid biopsy. This trial plans to recruit 540 patients, with 178 evaluable patients per study cohort. A histopathological and molecular genetic evaluation will be performed by the affiliated pathology departments of the national network for genomic medicine in lung cancer (nNGM), Germany. We will compare the diagnostic value of solid tumor tissue, lymph node cells and liquid biopsy for the molecular genetic characterization of NSCLC. This reflects a real world clinical setting, with potential direct impact on both treatment and survival

A significant proportion of classic Hodgkin lymphoma recurrences represents clonally unrelated second primary lymphoma

Despite high cure rates in classic Hodgkin lymphoma (cHL), relapses are observed. Whether relapsed cHL represents second primary lymphoma or an underlying T-cell lymphoma (TCL) mimicking cHL is under-investigated. To analyze the nature of cHL recurrences, in-depth clonality testing of immunoglobulin (IG) and T-cell receptor (TR) rearrangements was performed in paired cHL diagnosis and recurrences of 60 patients, supported by targeted mutation analysis of lymphoma-associated genes. Clonal IG rearrangements were detected by next-generation sequencing (NGS) in 69/120 (58%) diagnosis and recurrence samples. The clonal relationship could be established in 34 cases, identifying clonally related relapsed cHL in 24/34 patients (71%). Clonally unrelated cHL was observed in 10/34 patients (29%) as determined by IG-NGS clonality assessment, and confirmed by the identification of predominantly mutually exclusive gene mutations in the paired cHL samples. In recurrences of &gt;2 years, ~60% of cHL patients for which the clonal relationship could be established showed a second primary cHL. Clonal TR gene rearrangements were identified in 14/125 samples (11%), and TCL-associated gene mutations were detected in 7/14 samples. Retrospective pathology review with integration of the molecular findings were consistent with an underlying TCL in 5 patients aged &gt;50 years. This study shows that cHL recurrences, especially after 2 years, sometimes represent a new primary cHL or TCL mimicking cHL, as uncovered by NGS-based IG/TR clonality testing and gene mutation analysis. Given the significant therapeutic consequences, molecular testing of a presumed relapse in cHL is crucial for subsequent appropriate treatment strategies adapted to the specific lymphoma presentation.</p

A significant proportion of classic Hodgkin lymphoma recurrences represents clonally unrelated second primary lymphoma

Despite high cure rates in classic Hodgkin lymphoma (cHL), relapses are observed. Whether relapsed cHL represents second primary lymphoma or an underlying T-cell lymphoma (TCL) mimicking cHL is under-investigated. To analyze the nature of cHL recurrences, in-depth clonality testing of immunoglobulin (IG) and T-cell receptor (TR) rearrangements was performed in paired cHL diagnosis and recurrences of 60 patients, supported by targeted mutation analysis of lymphoma-associated genes. Clonal IG rearrangements were detected by next-generation sequencing (NGS) in 69/120 (58%) diagnosis and recurrence samples. The clonal relationship could be established in 34 cases, identifying clonally related relapsed cHL in 24/34 patients (71%). Clonally unrelated cHL was observed in 10/34 patients (29%) as determined by IG-NGS clonality assessment, and confirmed by the identification of predominantly mutually exclusive gene mutations in the paired cHL samples. In recurrences of &gt;2 years, ~60% of cHL patients for which the clonal relationship could be established showed a second primary cHL. Clonal TR gene rearrangements were identified in 14/125 samples (11%), and TCL-associated gene mutations were detected in 7/14 samples. Retrospective pathology review with integration of the molecular findings were consistent with an underlying TCL in 5 patients aged &gt;50 years. This study shows that cHL recurrences, especially after 2 years, sometimes represent a new primary cHL or TCL mimicking cHL, as uncovered by NGS-based IG/TR clonality testing and gene mutation analysis. Given the significant therapeutic consequences, molecular testing of a presumed relapse in cHL is crucial for subsequent appropriate treatment strategies adapted to the specific lymphoma presentation.</p