ABSTRACT
IMPORTANCE: Keratocystic odontogenic tumors (KCOTs) of the jaw affect more than 65% of patients with basal cell nevus syndrome (BCNS). Surgery frequently causes facial disfigurement and is not always curative. Most BCNS-related and some sporadic KCOTs have malignant activation of the Hedgehog signaling pathway. OBSERVATIONS: We examined the effect of vismodegib (an oral Hedgehog pathway inhibitor) on KCOT size in patients with BCNS enrolled in a clinical trial testing vismodegib for basal cell carcinoma prevention (NCT00957229), using pretreatment and posttreatment magnetic resonance imaging. Four men and 2 women had pretreatment KCOTs (mean longest diameter, 2.0 cm; range, 0.7-3.3 cm), occurring primarily in the mandible. Patients were treated with vismodegib, 150 mg/d, for a mean (SD) of 18.0 (4.8) months (range, 11-24 months). Four patients experienced a size reduction and 2 had no change. Vismodegib reduced the mean longest diameter of KCOTs in all patients by 1.0 cm (95% CI, 0.03-1.94; P = .02) or 50% from baseline. We observed no enlargement of existing KCOTs or new KCOT development. CONCLUSIONS AND RELEVANCE: Vismodegib shrinks some KCOTs in patients with BCNS and may offer an alternative to surgical therapy. These effects were maintained for at least 9 months after drug cessation in 1 patient. Further studies assessing long-term efficacy and optimal maintenance regimens should be performed.
Subject(s)
Anilides/administration & dosage , Basal Cell Nevus Syndrome/drug therapy , Jaw Neoplasms/drug therapy , Odontogenic Tumors/drug therapy , Pyridines/administration & dosage , Skin Neoplasms/drug therapy , Adult , Basal Cell Nevus Syndrome/mortality , Basal Cell Nevus Syndrome/pathology , Biopsy, Needle , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Humans , Immunohistochemistry , Jaw Neoplasms/complications , Jaw Neoplasms/pathology , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neoplasm Invasiveness/pathology , Neoplasm Staging , Odontogenic Tumors/mortality , Odontogenic Tumors/pathology , Patient Selection , Prognosis , Prospective Studies , Risk Assessment , Skin Neoplasms/mortality , Skin Neoplasms/pathology , Survival Analysis , Treatment OutcomeABSTRACT
Sporadic human basal cell carcinomas (BCC) are generally well managed with current surgical modalities. However, in the subset of high-risk patients predisposed to developing large numbers of BCCs, there is an unmet need for effective, low-morbidity chemoprevention. This population includes fair-skinned patients with extensive sun exposure and those with genodermatoses such as the basal cell nevus (Gorlin) syndrome (BCNS). Tazarotene (Tazorac, Allergan) is a topical retinoid with relative specificity for RAR-ß and RAR-γ receptors. We previously demonstrated tazarotene's robust anti-BCC efficacy in Ptch1(+/-) mice, a murine equivalent of BCNS, and others have found it to have some efficacy against sporadic human BCCs. We report here results of a randomized, double-blind, vehicle-controlled study in patients with BCNS evaluating the efficacy of topically applied tazarotene for BCC chemoprevention (N = 34 subjects), along with an open-label trial evaluating tazarotene's efficacy for chemotherapy of BCC lesions (N = 36 subjects) for a maximum follow-up period of 3 years. We found that only 6% of patients had a chemopreventive response and that only 6% of treated BCC target lesions were clinically cured. Our studies provide no evidence for either chemopreventive or chemotherapeutic effect of tazarotene against BCCs in patients with BCNS.
