1. Early detection of T-cell lymphoma with T follicular helper phenotype by RHOA mutation analysis
- Author
-
Hesham EI‐Daly, Peter Y Du, John W Grant, E. Joanna Baxter, Elizabeth Soilleux, Andrew Wotherspoon, Hala Rashed, Margarete A. Fabre, Hongxiang Liu, Manuel Rodriguez-Justo, Calogero Casa, George A Follows, Ayoma D. Attygalle, Ming-Qing Du, Penny Wright, Rachel Dobson, Wen-Qing Yao, Lívia Rásó-Barnett, Zi Chen, Lorant Farkas, and George S. Vassiliou
- Subjects
0301 basic medicine ,Pathology ,medicine.medical_specialty ,RHOA ,Lymphoma, T-Cell ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,T-cell lymphoma ,Allele frequency ,biology ,business.industry ,Lymphoma, T-Cell, Peripheral ,T-Lymphocytes, Helper-Inducer ,Hematology ,medicine.disease ,Phenotype ,Lymphoma ,Early Diagnosis ,030104 developmental biology ,Real-time polymerase chain reaction ,Immunoblastic Lymphadenopathy ,030220 oncology & carcinogenesis ,Mutation ,Mutation (genetic algorithm) ,biology.protein ,Mutation testing ,rhoA GTP-Binding Protein ,business - Abstract
Angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma with T follicular helper phenotype (PTCL-TFH) are a group of complex clinicopathological entities that originate from T follicular helper cells and share a similar mutation profile. Their diagnosis is often a challenge, particularly at an early stage, because of a lack of specific histological and immunophenotypic features, paucity of neoplastic T cells and prominent polymorphous infiltrate. We investigated whether the lymphoma-associated RHOA Gly17Val (c.50G>T) mutation, occurring in 60% of cases, is present in the early “reactive” lesions, and whether mutation analysis could help to advance the early diagnosis of lymphoma. The RHOA mutation was detected by quantitative polymerase chain reaction with a locked nucleic acid probe specific to the mutation, and a further peptide nucleic acid clamp oligonucleotide to suppress the amplification of the wild-type allele. The quantitative polymerase chain reaction assay was highly sensitive and specific, detecting RHOA Gly17Val at an allele frequency of 0.03%, but not other changes in Gly17, nor in 61 controls. Among the 37 cases of AITL and PTCL-TFH investigated, RHOA Gly17Val was detected in 62.2% (23/37) of which 19 had multiple biopsies including preceding biopsies in ten and follow-up biopsies in 11 cases. RHOA Gly17Val was present in each of these preceding or follow-up biopsies including 18 specimens that showed no evidence of lymphoma by combined histological, immunophenotypic and clonality analyses. The mutation was seen in biopsies 0-26.5 months (mean 7.87 months) prior to the lymphoma diagnosis. Our results show that RHOA Gly17Val mutation analysis is valuable in the early detection of AITL and PTCL-TFH.
- Published
- 2021