title: Extranodal CD20-positive peripheral T-cell lymphoma presenting with adrenal and testicular masses.
abstract: We report a case of extranodal CD20-positive peripheral T-cell lymphoma (PTCL). A 59-year-old man was admitted because of a right testicular mass in April 2006. CT scan revealed bilateral adrenal masses and he underwent right orchiectomy. The enlarged testis showed diffuse infiltration of large CD20-positive lymphocytes with slight CD3-positive cells. These cells were negative for CD10 and showed a high MIB-1 index. The pathological diagnosis was diffuse large B-cell lymphoma. He received R-CHOP, but developed brain involvement. He received whole brain radiotherapy following high-dose methotrexate, but he died of disease progression in August 2007. At autopsy, lymphoma cells were definitely positive for CD3 and negative for CD20. Monoclonal TCR gamma gene rearrangement was detected in the brain specimen without IgH rearrangement by PCR. The testicular tumor also showed the same clonal bands. Immunohistochemical re-evaluation of the testis showed CD20+, CD79a-, PAX5-, MUM1-, CD3 p+, CD5 p+, CD4-, CD8-, CD7 p+, granzyme B+, and TIA1+. Based on the clinical course and immunohistology, we finally diagnosed this case as extranodal PTCL-nos (not otherwise specified) with aberrant CD20 expression, which is extremely rare. The detection of gene rearrangement, plural immunohistochemical markers and knowledge of the possibility of CD20+ PTCL-nos are necessary for such cases.
authors.affiliation: Department of Hematology, Okayama City Hospital, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Makita
authors.forename: Ichiro
authors.initials: I
authors.lastname: Murakami
authors.forename: Takanori
authors.initials: T
authors.lastname: Yoshioka
authors.forename: Hisaaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Kenji
authors.initials: K
authors.lastname: Imajo
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Takata
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yoshino
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000473:pathology; D018951:Antigens, CD20 / Q000032:analysis*; D001932:Brain Neoplasms / Q000175:diagnosis / Q000473:pathology; D017252:CD3 Complex / Q000032:analysis; D017809:Fatal Outcome; D015321:Gene Rearrangement; D006801:Humans; D016411:Lymphoma, T-Cell, Peripheral / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D013736:Testicular Neoplasms / Q000175:diagnosis* / Q000473:pathology
chemical_list: D018951:Antigens, CD20; D017252:CD3 Complex; D011948:Receptors, Antigen, T-Cell