Histologically Agressive Basal Cell Carcinoma With Particular Emphasis On Galeal Infiltration Of The Scalp

Familiarity with predictors of more aggressive behavior is crucial to the management of basal cell carcinoma (BCC). Risk factors for aggressive BCC are essentially divided into clinical and histopathologic factors. In this review we examine histopathologic features predictive of aggressiveness in BCC. The morpheaform, infiltrative, micronodular, metatypical, and basosquamous subtypes and BCC with sarcomatoid differentiation are classically considered predictive of aggressive behavior. However, 2 other features associated with aggressive BCC are perineural invasion (invasion of nerves below the dermis or nerves larger than 0.1mm in caliber) and subgaleal extension. While the former is well known and widely described in the literature, the latter is not generally recognized as a risk factor, even though it is predictive of highly aggressive behavior. In this review, we draw attention to its importance.