CD20 is a 35 kDa transmembrane protein involved in B-cell activation. It is expressed early in B-cell ontogeny with loss of expression in terminal B-cell differentation2.

All available antibodies are reactive in paraffin-embedded tissue1.

Immunohistochemical expression

It is usually negative in:

Diagnostic utility

See: comparison of sensitivities and specificities of T and B cell markers


1 Leong A S-Y, Cooper K and Leong FJ W-M. Manual of diagnostic antibodies for immunohistology. 2nd edition, 2003

2 Quintanilla-Martinez L, Preffer F, Rubin D, et al. CD20+ T-cell lymphoma. Neoplastic transformation of a normal T-cell subset. Am J Clin Pathol 1994; 102:483-9

3 Yokose N, Ogata K, Sugisaki Y, et al. CD20-positive T cell leukemia/lymphoma: case report and review of the literature. Ann Hematol 2001; 80:372-5

©SMUHT/PW Bishop