Figure Legend:
Figure 1: A skin biopsy of SPTCL with increased γδ T cells. A
and B, the skin lesions show a spectrum of plaques, subcutaneous nodules
and so on. The skin biopsy reveals an ulcerated lesion with extensive
dermal and subcutaneous lymphoid infiltrate (C, H&E, 20x). Repeated PCR
for T-cell gene rearrangements in multiple skin biopsies confirms a
persistent clonal gene rearrangement (D). On high power, the H&E
sections show a adipose rimming by atypical lymphocytes (E, H&E 200x
and F, H&E, 400x). The atypical lymphocytes are predominantly CD3+ T
cells (G, 200X), CD8+ (H, 200x) with high Ki67 proliferation rate (I,
200x). TCR delta stains a marked increase of atypical T lymphocytes (K,
200x), although TCR BF1 also highlights substantial T lymphocytes (L,
200X). CD79a, CD123 and EBER-ISH are mostly negative (not shown).
Figure 2: A skin biopsy of γδ variant of PLC. The H&E sections
reveals parakeratosis, psoriasiform epidermal hyperplasia with minimal
spongiosis but exuberant lymphocyte exocytosis multifocally tagging
along the dermoepidermal junction and forming small clusters (A, H&E,
200x; B, H&E, 400X) within the epidermis. The dermis features a mildly
dense perivascular lymphohistiocytic infiltrate. Immunohistochemical
stains reveal a population of CD3+ T lymphocytes (C, 200X) with very
rare CD20+ B lymphocytes (not shown). CD5 (D, 200X) and CD7 (not shown)
expressions are diminished compared to epidermal CD3 expression. CD4 (E,
200x) and CD8 (F, 200X) expression are decreased within the epidermis.
TCR-Delta highlights an increase in γδ T cells (G, 200x). CD30 (H, 200x)
is largely negative. Neither fungal microorganisms nor basement membrane
changes are seen with interpretation of PAS histochemical stain (not
shown). PCR for T-cell gene rearrangements were positive.