cHL expressing TCAs. (A) Scattered HRS cells amid a background rich in histiocytes and lymphocytes. (B-D) The neoplastic cells express variable weak CD20 (CD20 immunoperoxidase, ×200), uniform CD30 (CD30 immunoperoxidase, ×100), and CD15 (CD15 immunoperoxidase, ×200 respectively. (E-G) CD3, CD4, and CD5 expression, respectively, on the HRS cells. There is membrane staining for CD3 (CD3 immunoperoxidase, ×400), CD4 (CD4 immunoperoxidase, ×400), and CD5, focally (CD5 immunoperoxidase, ×400); additionally, CD3 and CD4 show blob-like cytoplasmic staining.