Lymphatics

Cerebrospinal fluid (CSF) liquid biopsy has been recently recommended by the National Comprehensive Cancer Network (NCCN) as a molecular diagnostic tool for central nervous system (CNS) lymphoma that offers a minimally invasive method to detect key biomarkers when traditional diagnostics are limited by sensitivity or feasibility. This brief report describes the clinical use of two novel CLIA/CAP-approved CSF liquid biopsy tests from Belay Diagnostics, Summit™ and Vantage™, to aid in the diagnosis and management of CNS lymphoma. Results from both tests were reviewed for 50 CSF samples in the context of clinical information provided with the test order. Summit™ and Vantage™ detected clinically significant alterations in CNS lymphoma-associated genes such as MYD88, CD79B, and TP53 as well as MGMT methylation when other modalities (e.g., CSF cytology, MRI, or brain biopsy) were inconclusive. In several cases of suspected secondary CNS lymphoma, Summit™ detected pathogenic genomic variants as well as mild to high levels of aneuploidy, suggesting CNS involvement. Belay testing impacted management in 41 of 50 (82%) cases by informing CNS lymphoma diagnosis, stratification, or progression as well as therapeutic response with an overall false negative rate of 18% (2/11). This report contributes to the growing body of literature that demonstrates how comprehensive molecular profiling of CSF enhances detection and characterization of CNS lymphoma and offers a promising adjunct to conventional diagnostics.

Therapy resistance remains a major cause of relapse and poor outcomes in acute lymphoblastic leukemia (ALL). Recent multi-omics studies in ALL have revealed that resistance arises from a combination of leukemia-specific genetic lesions, treatment-driven clonal evolution, and adaptive non-genetic programs. Genomic analyses have identified recurrent alterations associated with resistance to chemotherapy, tyrosine kinase inhibitors, and immunotherapies, while single-cell profiling has uncovered heterogeneous cell states that persist during treatment and contribute to minimal residual disease. Emerging epigenetic, proteomic, and metabolic data further indicate that reversible regulatory and signaling changes play a central role in leukemic persistence. Integrative analyses are beginning to define convergent resistance pathways and clinically relevant biomarkers, although longitudinal sampling and clinical translation remain limited. This review summarizes the current multi-omics landscape of therapy resistance in ALL and discusses opportunities to improve risk stratification and therapeutic strategies.

The World Health Organization (WHO) and International Consensus Classification (ICC) systems have classified EBV-positive NK/T-cell neoplasms in adults and EBV-positive T/NK-cell lymphoid lymphoproliferative disorders (LPD) in children. Recent molecular profiling techniques have revealed the pathogenesis of these disorders, showing interactions among EBV-encoded proteins, host immune responses, and genetic alterations. Extranodal NK/T-cell lymphoma (ENKTL) shows molecular diversity, with various subtypes (TSIM, MB, and HEA) identified through a multiomics approach. Aggressive NK-cell leukemia (ANKL) has mutations in JAK/STAT, epigenetic regulators, and TP53 pathways. EBV-positive nodal T- and NK-cell lymphoma (ENTNKL) is a new entity, distinguished by primary nodal presentation and a unique molecular profile. Severe mosquito bite allergy (SMBA), hydroa vacciniforme lymphoproliferative disorder (HVLPD), and systemic chronic active EBV disease (CAEBV) are rare childhood EBV-driven LPDs defined by clinico-pathologic criteria, with largely unexplored genomic landscapes. Studies of CAEBV samples have found ENKTL-like driver mutations, including DDX3X and KMT2D, in EBV-infected NK/T cells, while KMT2D and chromatin modifier mutations were common in HVLPD. Comprehensive molecular sequencing of SMBA and Systemic EBV-positive T-cell lymphoma of childhood remains lacking. These findings suggest all EBV⁺ NK/T-cell LPDs exist on a biological continuum of viral oncogenesis. The integration of clinical, pathological, and molecular information aims to create a more accurate classification system, enabling better risk evaluation and tailored treatment strategies for patients with these complex disorders.