Track

Case Reports

Abstract

A 40-year-old woman presented to dermatology clinic with a one-year history of a diffuse pink, scaly rash involving 90% of her body surface area (BSA). History and exam findings were consistent with psoriasis which was supported by two prior biopsies. Guselkumab was initiated with minimal response. Cyclosporine was subsequently trialed with significant improvement, though hypertension precluded continuation. Loading doses of ixekizumab were followed by eruption with innumerable bright pink plaques, nodules, and tumors—some with thick, hyperkeratotic scale—affecting over 90% BSA. Punch biopsy showed a dense infiltrate of large, hyperchromatic CD3+ lymphocytes with epidermotropism and subcutaneous infiltration. T cell receptor delta IHC was negative. Subsequent PET/CT showed diffuse hypermetabolic lymphadenopathy. Histopathologic analysis confirmed the diagnosis of peripheral T-cell lymphoma not otherwise specified (PTCL-NOS). She began treatment with cyclophosphamide, doxorubicin, etoposide, vincristine, and prednisone (CHOEP) x 6 cycles with excellent skin response initially. However, biopsy-confirmed flares of psoriasis occurred between cycles, correlating with cessation of prednisone from the prior cycle. Within three months, she experienced severe worsening of her skin disease. Repeat biopsy demonstrated prominent T-cell lymphoma consistent with disease progression. Unfortunately, she passed away 5 months after diagnosis with PTCL-NOS. This case demonstrates a true coexistence of psoriasis and CTCL through multiple temporally spaced biopsies and an apparent unmasking of an aggressive peripheral T-cell lymphoma during treatment of psoriasis with ixekizumab. An association between psoriasis and increased risk of malignancy, particularly lymphomas, has been previously reported, although a direct causal relationship has not yet been established.