Nodal involvement by cutaneous CD30-positive T-cell lymphoma mimicking classical Hodgkin lymphoma

Abstract

An association between classical Hodgkin lymphoma (cHL) and mycosis fungoides (MF) or lymphomatoid papulosis has been reported in the literature. However, there can be considerable morphologic and immunophenotypic overlap between cHL and nodal involvement by CD30-positive T-cell lymphoproliferative disorders (CD30-T-LPD). To examine this potential association, biopsies from patients with a history of MF or primary cutaneous CD30-T-LPD and lymph node biopsies reported as either CD30-positive T-cell lymphoma (TCL) with Hodgkin-like cells or cHL were retrieved from the authors' institution. Of 11 cases identified, 10 were considered CD30-positive TCL with Hodgkin-like cells, whereas 1 was confirmed as cHL upon review. Five cases originally diagnosed as cHL were revised as CD30-positive TCL. Cases of CD30-positive TCL with Hodgkin-like cells showed a male predominance (M:F, 4:1) with a median age of 53 years (range, 44 to 72 y). Nearly all patients (9/10) initially presented with skin lesions. In 7/10 patients the draining lymph node was involved, whereas in 3 cases this could not be confirmed. Tumor cells morphologically resembled Hodgkin/Reed-Sternberg cells; they were uniformly strongly positive for CD30, and CD15 was expressed in 9/10 (90%) cases. A T-cell derivation was confirmed by T-cell antigen expression (7/10) and clonal rearrangement of T-cell receptor genes (9/10). In 3 cases a common T-cell clone was identified in skin and lymph node. B-cell markers (CD20/PAX5) were consistently negative. In 1 case the diagnosis of cHL followed by lymphomatoid papulosis was confirmed, with Hodgkin/Reed-Sternberg cells expressing PAX5, CD30, and CD15. In situ hybridization studies for Epstein Barr virus were negative. We show that cHL is less often associated with MF and primary cutaneous CD30-T-LPD than previously thought and that the coexpression of CD30 and CD15 in these TCLs may lead to a mistaken diagnosis of cHL.

Figure 1

A. CD30-positive T-cell lymphoma with Hodgkin-like cells involving the lymph node. (Case 2) B. At higher power tumor cells infiltrate in sheets and show variability in size, irregular nuclear contours, vesicular chromatin, and prominent nucleoli (inset) reminiscent of HRS cells. C. Lacunar-like cells were seen in some cases (Case 1). D. Some cases had a thickened capsule and broad bands of fibrosis mimicking cHL, nodular sclerosis subtype (Case 2). E. CD30 highlights the tumor cells forming nodular aggregates divided by dense fibrosis, and (inset) the variability in cell size of the tumor cells (Case 2). F. The HRS-like cells are positive for CD15 (Case 9) but negative for PAX5 (not shown) G. Sinusoidal infiltration was prominent in most cases (Case 5). H. Tumor cells are positive for T-cell-associated markers such as CD2 (Case 1).

Figure 2

A. Skin biopsy (Case 8) shows features of LyP with a dense dermal infiltrate composed of (B) atypical medium to large cells that are positive for CD8 (C) and CD3 (inset), as well as CD30 (D). E. The same patient had an inguinal node containing a pleomorphic infiltrate with sinusoidal infiltration by (F) large HRS-like cells that were positive for CD30 (G) , CD15 (inset), and CD8 (H).

Figure 3

A. Lymph node (Case 11) with features of cHL, mixed cellularity subtype. HRS cells are present in an inflammatory background. B. The HRS cells are positive for CD30 as well as PAX5 (inset), showing dim staining for the latter. C. The skin biopsy shows a wedge-shaped infiltrate sparing the epidermis composed of (D) large atypical cells in a background of histiocytes, small lymphocytes, and eosinophils.

Figure 4

T-cell receptor γ chain gene rearrangement studies of CD30-positive T-cell lymphoma with Hodgkin-like cells (Case 6) identified clonal peaks of identical size in the microdissected tumor cells of the skin biopsy (A) and the lymph node biopsy (B), whereas DNA from microdissected background T-lymphocytes were polyclonal TCR gene rearrangements (C).