Figure 1

Representative tissue samples at 400× magnification. The initial L4 vertebral core biopsy (a) shows marrow replacement by a mixed inflammatory infiltrate consisting of small lymphocytes and some neutrophils in a fibrotic background. Rare large cells are present (arrow), but diagnostic Reed-Sternberg (RS) cells are not identified. Trilineage hematopoietic marrow was present in other areas (not shown). The right inguinal lymph node core biopsy (b) demonstrates a mixed inflammatory infiltrate consisting of small lymphocytes, histiocytes and eosinophils in a fibrotic stroma. Rare large degenerated cells are also present (arrow) but are non-specific findings. The left anterior cervical lymph node excisional biopsy (c) shows architectural effacement by a polymorphous infiltrate that includes scattered eosinophils, as well as diagnostic multinucleated RS cells (blue arrow) and mononuclear variants (black arrows) that stain positively for CD30 by immunohistochemistry (d).