Multi-omics Profiling of Relapsed Extranodal Natural Killer (NK)/T-cell Lymphoma

This retrospective observational study characterises the tumour immune microenvironment and clonal architecture of relapsed or refractory extranodal NK/T-cell lymphoma (ENKTCL). Archival tumour tissue and blood samples collected during routine care are profiled by single-cell RNA sequencing, T-cell and B-cell receptor repertoire sequencing, whole-exome sequencing, and spatial transcriptomics. The study examines how immune and stromal cell states, clonal composition and spatial organisation relate to response to programmed cell death protein 1 (PD-1) blockade and to subsequent relapse.

Inclusion Criteria: * Histologically confirmed extranodal NK/T-cell lymphoma, nasal type * Relapsed or refractory disease after at least one prior line of therapy, or archival tissue available from a relapse episode * Archival formalin-fixed paraffin-embedded tumour tissue and/or peripheral blood available for molecular profiling * Received PD-1 or PD-L1 blockade as part of routine care at any point in the disease course * Written informed consent for the use of residual clinical specimens in research, or a waiver of additional consent granted by the institutional ethics committee Exclusion Criteria: * Insufficient tissue or nucleic acid quality for the planned profiling assays * Incomplete clinical records precluding assessment of response or outcome