The Pathologic and Genetic Characteristics of Extranodal NK/T-Cell Lymphoma

Extranodal NK/T-cell lymphoma is a neoplasm of NK cells or cytotoxic T cells presenting in extranodal sites, most often in the nasal cavity. The typical immunophenotypes are cCD3+, sCD3−, CD4−, CD5−, CD8−, CD16−, and CD56+ with the expression of cytotoxic molecules. Tumor subsets express NK cell receptors, CD95/CD95L, CD30, MYC, and PDL1. Virtually all the tumor cells harbor the EBV genome, which plays a key role in lymphomagenesis as an epigenetic driver. EBV-encoded oncoproteins modulate the host-cell epigenetic machinery, reprogramming the viral and host epigenomes using host epigenetic modifiers. NGS analysis revealed the mutational landscape of ENKTL, predominantly involving the JAK–STAT pathway, epigenetic modifications, the RNA helicase family, the RAS/MAP kinase pathway, and tumor suppressors, which indicate an important role of these pathways and this group of genes in the lymphomagenesis of ENKTL. Recently, three molecular subtypes were proposed, the tumor-suppressor/immune-modulator (TSIM), MGA-BRDT (MB), and HDAC9-EP300-ARID1A (HEA) subtypes, and they are well-correlated with the cell of origin, EBV pattern, genomic alterations, and clinical outcomes. A future investigation into the function and interaction of discovered genes would be very helpful for better understanding the molecular pathogenesis of ENKTL and establishing better treatment strategies.

Bilateral intraocular and lung involvements associated with Nasal NK/T-cell lymphoma

Background To report a rare case of nasal natural killer/T (NK/T) cell lymphoma with bilateral intraocular and lung metastasis and to further describe the clinical features of intraocular manifestations. Case presentation A 54-year-old man presented with a 3-month history of left nasal congestion, and bilateral vision impairment of one week duration. Subsequent maxillary computed tomography (CT) and multiple biopsies confirmed the diagnosis of nasal NK/T-cell lymphoma. EBV-encoded small RNA (EBER) in situ hybridization revealed EBV infection. A comprehensive ophthalmic examination found lymphoma-associated retinopathy and choroidopathy, which presented as bilateral diverse patterns and retinal detachment. In addition, the chest CT showed multiple scattered nodules in both lungs, and soft-tissue mass in the left hilum with mediastinal and axillary lymphadenopathy. The condition of this patient deteriorated rapidly and he died shortly after diagnosis. Conclusions The rarity of secondary ocular NK/T-cell lymphoma makes it challenging to identify these tumors early. Both otolaryngologist and ophthalmologists should be aware of ocular involvement and other secondary manifestations of NK/T-cell lymphoma.

The identification of gene signatures in patients with extranodal NK/T-cell lymphoma from a pair of twins

Background There is no unified treatment standard for patients with extranodal NK/T-cell lymphoma (ENKTL). Cancer neoantigens are the result of somatic mutations and cancer-specific. Increased number of somatic mutations are associated with anti-cancer effects. Screening out ENKTL-specific neoantigens on the surface of cancer cells relies on the understanding of ENKTL mutation patterns. Hence, it is imperative to identify ENKTL-specific genes for ENKTL diagnosis, the discovery of tumor-specific neoantigens and the development of novel therapeutic strategies. We investigated the gene signatures of ENKTL patients. Methods We collected the peripheral blood of a pair of twins for sequencing to identify unique variant genes. One of the twins is diagnosed with ENKTL. Seventy samples were analyzed by Robust Multi-array Analysis (RMA). Two methods (elastic net and Support Vector Machine-Recursive Feature Elimination) were used to select unique genes. Next, we performed functional enrichment analysis and pathway enrichment analysis. Then, we conducted single-sample gene set enrichment analysis of immune infiltration and validated the expression of the screened markers with limma packages. Results We screened out 126 unique variant genes. Among them, 11 unique genes were selected by the combination of elastic net and Support Vector Machine-Recursive Feature Elimination. Subsequently, GO and KEGG analysis indicated the biological function of identified unique genes. GSEA indicated five immunity-related pathways with high signature scores. In patients with ENKTL and the group with high signature scores, a proportion of functional immune cells are all of great infiltration. We finally found that CDC27, ZNF141, FCGR2C and NES were four significantly differential genes in ENKTL patients. ZNF141, FCGR2C and NES were upregulated in patients with ENKTL, while CDC27 was significantly downregulated. Conclusion We identified four ENKTL markers (ZNF141, FCGR2C, NES and CDC27) in patients with extranodal NK/T-cell lymphoma.