Stromal α-Smooth Muscle Actin Positivity Is Associated With High-Risk Basal Cell Carcinomas.

ABSTRACT: The presence of myofibroblast differentiation has been proposed as an invading mechanism in basal cell carcinomas. However, small studies regarding α-smooth muscle actin positivity have led to conflicting results. This review of 100 cases examines the association between α-smooth muscle actin positivity on immunohistochemical studies and the clinical and histopathological characteristics of the tumor, including tumor size, thickness, subtype, topography, ulceration, 5-year recurrence rate, and age at diagnosis.