Eric Allan Severson

Comprehensive Genomic Profiling of 282 Pediatric Low‐ and High‐Grade Gliomas Reveals Genomic Drivers, Tumor Mutational Burden, and Hypermutation Signatures

This study highlights the value of comprehensive genomic profiling in the largest known cohort of pediatric glioma patients and explores the most common alterations across diagnosis and anatomic location. Tumor mutational burden and associated genetic factors that may predispose patients to developing a hypermutator phenotype are also discussed.

Genomic Characterization of Testicular Germ Cell Tumors Relapsing After Chemotherapy

BACKGROUND Although both seminomatous and nonseminomatous testicular germ cell tumors (TGCTs) have favorable outcomes with chemotherapy, a subset is chemorefractory, and novel therapeutic options are needed. OBJECTIVE To molecularly characterize chemotherapy-refractory TGCTs. DESIGN, SETTING, AND PARTICIPANTS Archival tissues from 107 chemotherapy-treated and relapsed TGCT patients (23 seminomas; 84 nonseminomas) underwent hybrid-capture-based genomic profiling to evaluate four classes of genomic alterations (GAs). Tumor mutational burden (TMB) and microsatellite instability (MSI) were also measured. INTERVENTION Genomic profiling on tumor samples from chemotherapy-refractory TGCTs. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Descriptive analyses and differences between seminoma and nonseminoma subgroups were reported. RESULTS AND LIMITATIONS The mean GA/tumor was 2.9 for seminomas and 4.0 for nonseminomas (p=0.04). KRAS alterations (mainly amplifications) were the most common GAs at the single-gene level (47.8% of seminomas and 51.2% of nonseminomas). RAS-RAF pathway (56.5% vs 52.3%) and cell-cycle pathway (52.2% vs 56.0%) were the most common GA classes in seminomas and nonseminomas, respectively. Receptor tyrosine kinase pathway and PI3K pathway GAs were more frequent in seminomas (p=0.02). Median TMB was 1.8 mutations/Mb for seminomas and 2.7 mutations/Mb for nonseminomas (p=0.098), and MSI-high status was found in one nonseminoma only (1.2%). A lack of clinical outcome correlation is a limitation of the present analyses. CONCLUSIONS In chemotherapy-refractory TGCTs, trials with agents targeting the KRAS pathway may be pursued due to the high frequency of KRAS GAs. Overall, the GAs found in refractory seminomas and nonseminomas differ significantly. Considering the frequency of high TMB or MSI-high status, immunotherapy may benefit a small subset of nonseminomas. PATIENT SUMMARY Testicular cancers that are resistant to or relapse after standard chemotherapy may harbor genomic alterations that are potentially druggable, particularly in the clinical trial setting, and genomic profiling can guide clinical research and disclose therapeutic opportunities for these patients.

Precision Neuro-oncology: the Role of Genomic Testing in the Management of Adult and Pediatric Gliomas

Opinion statementIn recent years, large-scale genomic studies have expanded our knowledge regarding genomic drivers in tumors of the central nervous system. While histopathologic analysis of brain tumors remains the primary method for tumor classification, the clinical utility of molecular and genomic testing to support and/or complement tumor classification continues to expand. This approach enhances diagnostic accuracy and provides clinicians with objective data to facilitate discussions regarding prognosis and treatment decisions, including selection of clinical trials. Ensuring accurate diagnoses is fundamental to the management of brain tumor patients. However, given the morphologic overlap among primary brain tumors, genomic data can be used to help distinguish tumor lineage. In its clearest form, we have embraced the concept of an integrated diagnosis, which combines traditional histopathology findings with molecular and genomic data. Patient prognosis varies significantly based on a tumor’s genomic profile. For neuro-oncology patients, outcome studies linking diagnoses with genomic profiles show significant differences based on tumor biomarkers such as IDH1/2, H3F3A, BRAF, and CDKN2A and TERT status. Therefore, easy access to reliable genomic data is important in understanding a patient’s disease and developing a clinical strategy wherein targeted molecular or immune therapies can be incorporated into the discussion.

Targeting HER2 in colorectal cancer: The landscape of amplification and short variant mutations in ERBB2 and ERBB3 : ERBB2 and ERBB3 in CRC

In contrast to lung cancer, few precision treatments are available for colorectal cancer (CRC). One rapidly emerging treatment target in CRC is ERBB2 (human epidermal growth factor receptor 2 [HER2]). Oncogenic alterations in HER2, or its dimerization partner HER3, can underlie sensitivity to HER2‐targeted therapies.

Detection of clonal hematopoiesis of indeterminate potential in clinical sequencing of solid tumor specimens

TO THE EDITOR: Clonal hematopoiesis of indeterminate potential (CHIP) describes an expansion of hematopoietic stem cells that harbor somatic mutations[1][1][⇓][2][⇓][3][⇓][4]-[5][5] without an underlying hematologic malignancy or definitive morphologic evidence of dysplasia.[6][6] CHIP can