Angioimmunoblastic T-cell lymphoma with dual genotype of TCR and IgH genes

A 70-year-old man complained of fever and sore throat accompanied by hoarseness of voice. On physical examination, there was no systemic abnormality but a mild lymphadenopathy of cervical lymph nodes. With laryngoscopy, there was a marked outgrowth of the bilateral palatine tonsils proximal to the vocal cord. The histology of the resected tumor was compatible with angioimmunoblastic T cell lymphoma (AITL), revealing the effacement of normal tonsillar architecture and small to medium-sized neoplastic cell proliferation around marked vascular proliferation and atrophic lymphoid follicles. Tumor cells were positive for conventional T-cell antigens as well as for the follicular helper T-cell marker, PD-1, and CXCL13. Large hodgkinoid cells, but no tumor cells, were positive for latent membrane protein-1 and Epstein-Barr virus-encoded small RNA (EBER)-1 (in situ hybridization). Non-neoplastic, double positive cells for EBER-1 and CD20 were also scattered. Southern blot analysis revealed dual TCR-Cβ1 and IGH-JH gene rearrangements. Although the swelling of bilateral inguinal and perigastric lymph nodes developed later, the radical resection of tumor and chemotherapy appeared to be effective for the treatment of AITL with clinical stage IIIa. We here report a rare case of AITL involving palatine tonsil as primary site and give a review of the literature.