LAUSR

Dear Editor, Epstein-Barr virus (EBV) positive diffuse large B cell lymphoma (EBV+DLBCL) may be seen in patients with peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) and angioimmunoblastic T cell lymphoma (AITL) [1–6]. Recently, conversion mutation from glycine to valine at the 17th nucleotide position of ras homolog family member A (G17V RHOA) has been identified in 60–70% cases of AITL and AITL-like PTCL-NOS by using quantitative allele-specific polymerase chain reaction (qAS-PCR) [7]. There is the first report of this mutation in EBV+DLBCL arising from PTCL-NOS. A 73-year-oldmanwas admitted to our hospital with systemic multiplelymphnode(LN)swellings,bilateralpleuraleffusion,and ascites.Hewasdiagnosedwith stage IVPTCL-NOSby left inguinal LN biopsy with high international prognostic index (IPI). He had CD3-cytoplasmic CD3+CD4+CD5+CD8-CD10and 46, XY,del(9)(q13q22)karyotype.Complete remissionwasachieved with etoposide, steroids, cytarabine, and cisplatin therapy because hewasrefractory to tetrahydropyranyladriamycin,cyclophosphamide, vincristine, and prednisolone (THP-COP) therapy. He had multiple LN swellings and skin lesions at 18 months post-treatment. He was diagnosed with stage IV EBV+DLBCL following left-leg skin biopsy with high IPI. He had CD5-CD10-CD11c+ CD19+CD20+κ+phenotype and46,XY, t(6;16)(q13;p13.1) karyotype. Southern blot analysis showed immunoglobulin JH rearrangement. EBVencoded RNA (EBER) was positive on in situ hybridization. Feature of follicular dendritic meshwork and Tcell lymphoma were not detected. We observed 7.5 × 10 and 3.8 × 10 G17V RHOA mutation in the PTCL-NOS formalinfixed/paraffin-fixed embedded (FFPE) LN sample and EBV+ DLBCL FFPE skin sample, respectively, by qAS-RT-PCR. He received 6 cycles of rituximab, gemcitabine, dexamethasone, and cisplatin (R-GDP) therapy and achieved complete remission forover6months.Wehadpreviouslyexaminedthismutationin15 FFPE samples of AITL and AITL-like PTCL-NOS. Eight of 15 (53.3%) cases were positive (> 1 × 10: range 2.8 × 102.5 × 10) (Fig. 1).