Diagnosis of gamma/delta mycosis fungoides requires longitudinal clinical observation
ST1: Abbreviations: mo, months; HTN, hypertension; C, Caucasian; LE, lower extremity; UE, upper extremity; CR, complete remission; PR, partial response; AWD, alive with disease; DOD, died of disease; IFN, Interferon-α-2a; Bex, bexarotene; Gem, gemcitabine; PUVA, psoralen (P) and ultraviolet A (UVA); NB-UVB, narrow band-ultraviolet B; BMT, bone marrow transplant. TNMB classifications and disease stages were based on the 2007 staging guidelines defined by the International Society of Cutaneous Lymphomas and the European Organisation for Research and Treatment of Cancer Cutaneous Lymphoma Task Force. ST2: lymphoid cells as positive if > 50% of cells showed staining, focally positive if 10-50% (+/-) of cells showed staining, and negative if <10% of cells showed staining. For CD2, CD5, and CD7, results were defined as preserved expression if >50% of cells were positive, and partial/subtotal loss of expression if <50% (+/-) of cells were positive. Molecular pathology results of T-cell receptor (TCR) gene rearrangement, including TCRγ and TCR𝛽 were a part of the routine workup and were retrieved from the medical records. The first row of Case 4 refers to the plaques and the second row to the tumours. EBER, EBV-encoded RNA; GB, granzyme B; TIA-1, T-cell intracellular antigen-1; TCR, T-cell receptor. SF1: A-B) Case 1 presenting with a ~ 5 cm confluent reddish-brown annular patch with overlying scale on the right lower abdomen and right flank. C-F) Case 2 initial cutaneous lesions exhibiting variable sized reddish brown annular patches and plaques with overlying scale to the trunk and left axillary region. F) Case 2 demonstrating stage progression with a dark red multi-lobed tumours with overlying scale involving the right nasal sidewall. G-H) Case 3 initially demonstrating erythematous scaly patches and plaques symmetrically on the trunk and proximal lower extremities and. I-J) Case 4 initially manifesting erythematous scaly patches and plaques on the trunk and upper extremities (E), and subsequently developing ulcerating tumours on the right plantar SF2: A) H&E reveals an atypical lymphoid infiltrate within the epidermis and reactive superficial dermal infiltrate. The epidermotropic lymphoma cells are small-to-medium size with perinuclear halos and hyperchromatic nuclei. Intraepidermal T-cells are negative for CD4 (B), CD8 (C), and Beta-F1 (D). Reactive superficial dermal infiltrate stains positive for Beta-F1 and CD4. Epidermotropic lymphoid cells strongly express TCR-δ (E) and cytotoxic marker TIA (F). G) H&E, atypical lymphoid infiltrate indistinguishable from that or early-stage MF and 2019 biopsy. A reactive superficial dermal infiltrate is noted. H) Epidermotropic lymphoid cells are positive for T-cell marker, CD3, show scant CD4 expression (I) and negative CD8 expression (J).