title: Indolent T-lymphoblastic proliferation: report of a case with a 16-year course without cytotoxic therapy.
abstract: T-lymphoblastic lymphoma is a high-grade malignant lymphoma. Clinically indolent T-lymphoblastic proliferations have not been described. We present a case report of an indolent T-cell lymphoblastic proliferation studied by histopathology, immunohistochemistry, flow cytometry, antigen receptor gene rearrangement studies, and cytogenetics. The patient had recurrent masses in the upper aerodigestive tract over a 16-year period, was treated by multiple surgical excisions, and never received either chemotherapy or radiotherapy. A proliferation of lymphoblasts was present histologically. The cells were positive for terminal deoxynucleotidyl transferase, CD1, and CD3, and coexpressed CD4 and CD8. No clonal rearrangements of the T-cell receptor beta or gamma chain genes were identified. Cytogenetic studies revealed a questionable inversion of the short arm of chromosome 9, affecting the 9p21-22 region. Although ectopic thymic tissue was considered, the case was considered to be an indolent lymphoblastic proliferation. It should be recognized that rare lymphoblastic proliferations may not behave in a high grade fashion as typically seen in T-lymphoblastic lymphoma.
authors.affiliation: Department of Pathology, University of Southern California School of Medicine, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Velankar
authors.forename: B N
authors.initials: BN
authors.lastname: Nathwani
authors.forename: M J
authors.initials: MJ
authors.lastname: Schlutz
authors.forename: L A
authors.initials: LA
authors.lastname: Bain
authors.forename: D A
authors.initials: DA
authors.lastname: Arber
authors.forename: M L
authors.initials: ML
authors.lastname: Slovak
authors.forename: L M
authors.initials: LM
authors.lastname: Weiss
mesh_terms: D000328:Adult; D004273:DNA, Neoplasm / Q000032:analysis; D005434:Flow Cytometry; D015321:Gene Rearrangement; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D011946:Receptors, Antigen / Q000235:genetics; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology*
chemical_list: D004273:DNA, Neoplasm; D011946:Receptors, Antigen