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Basal cell carcinomas are the most common form of skin cancer. Tazarotene is a retinoic acid receptor selective retinoid that upregulates a tumor suppressor, tazarotene-induced gene 3 (TIG-3), in keratinocytes and psoriasis. Expression of TIG-3 in basal cell carcinomas was studied in an opened-label pilot biomarker study of 22 patients with basal cell carcinomas who applied tazarotene 0.1% gel for up to 12 wk prior to excision. Nineteen paired baseline and treated specimens were compared using immunohistochemistry and in situ hybridization. Compared to overlying normal epidermis, TIG-3 protein and mRNA were decreased in 14 and 18 of 19 basal cell carcinomas (74% and 95%), respectively (p < 0.001). Tazarotene treatment was associated with increased TIG-3 protein and mRNA expression in basal cell carcinomas compared to baseline levels (p < or = 0.001 and p = 0.028, respectively). Sixty percent of basal cell carcinomas treated with tazarotene decreased in size by at least 25%. Ten of 19 lesions improved histologically, including three complete responses. There was a correlation between the increased expression of TIG-3 protein and histologic improvement (p = 0.020), suggesting that suppression of TIG-3 may underlie the development of basal cell carcinomas. This association suggests that reversal of TIG-3 expression may help to explain the mechanism of retinoid action in epidermal differentiation and chemoprevention.

Peripheral T-cell lymphomas (PTCLs) are an uncommon and heterogeneous group of well-differentiated, post-thymic T-cell malignancies that can present in the skin as cutaneous T-cell lymphomas. In general, their prognosis is poor, and specific therapy is not well defined. We report the successful treatment of a patient with relapsed, refractory PTCL who after failing 13 standard single and multiple chemotherapy regimens and experimental agents had a dramatic prolonged response to diftitoxin denileukin (ONTAK). This fusion protein, composed of diphtheria toxin coupled to interleukin-2, is approved for cutaneous T-cell lymphomas, including mycosis fungoides, and should be considered for treatment of the rare subset of peripheral T-cell lymphomas.

No abstract

Background: Lymphomatoid papulosis (LyP) is a clonal T cell proliferation with large cell histology, a chronic course, and an increased risk of lymphoma. Bexarotene (Targretin^®) is an RXR-selective retinoid (rexinoid) approved for the cutaneous manifestations of cutaneous T cell lymphoma. Objective: To determine whether bexarotene is effective in treating LyP. Methods: Ten patients with chronic and symptomatic LyP were prospectively treated with oral (n = 3) or topical gel (n = 7) formulations of bexarotene. Results: A favorable response to bexarotene treatment with decreased numbers or duration of lesions was seen in all with objective responses in 8 patients. Conclusions: Bexarotene may be an effective palliative treatment for LyP, warranting further controlled studies.