title: Expression of thymidine phosphorylase in lymph nodes involved with mycosis fungoides and sézary syndrome.
abstract: Thymidine phosphorylase may be overexpressed in both neoplastic cells and tumor stromal cells in a variety of malignancies. Our study explores thymidine phosphorylase expression in lymph nodes (LNs) from patients with mycosis fungoides (MF) or Sézary syndrome (SS). In MF/SS, the LNs may have a pathologic diagnosis of either dermatopathic lymphadenopathy (LN-DL) or involvement by MF/SS (LN-MF). We performed immunohistochemical staining on MF/SS lymph nodes using antibodies to thymidine phosphorylase, CD68, CD21, CD3, and CD4. In both LN-DL and benign nodes, thymidine phosphorylase staining was noted only in macrophages, dendritic cells, and endothelial cells. In LN-MF, thymidine phosphorylase expression was also noted in subsets of intermediate to large neoplastic T cells. Concurrent CD68, CD21, CD3, and CD4 staining supported the above observations. Similar results were noted in the skin and in LN-MF with large cell transformation. Other T-cell lymphomas were also examined (total 7 cases); only enteropathy-type T-cell lymphoma (1 case) showed TP positivity in neoplastic T lymphocytes. We demonstrated that thymidine phosphorylase staining is present in neoplastic T cells in mycosis fungoides. The exact mechanism needs further investigation.
authors.affiliation: Department of Pathology, Drexel University College of Medicine, 245 N. 15th Street, Mail Stop 435, Philadelphia, PA 19102, USA.
authors.forename: Xingcao
authors.initials: X
authors.lastname: Nie
authors.forename: Rekha
authors.initials: R
authors.lastname: Bhat
authors.forename: Essel Dulaimi
authors.initials: ED
authors.lastname: Al-Saleem
authors.forename: Eric C
authors.initials: EC
authors.lastname: Vonderheid
authors.forename: J Steve
authors.initials: JS
authors.lastname: Hou