In this study, we retrospectively investigated 70 cases of EN-NK/T-NT, carried out fluorescence in situ hybridization (FISH) test on formalin-fixed paraffin-embedded (FFPE) tumor specimens and NK/T lymphoma cell lines, clarified the deletion status of chromosome 6q21 and specific PRDM1 gene, and evaluated the clinical significances and prognostic factors. Here, PRDM1 is linked to neoplasm.