Basal Cell Carcinoma

Overview
  • Basal Cell Carcinoma (BCC) is a neoplasm of the epidermal basal cell and represents the most common malignancy of humans. The primary risk factor for BCCs is life-long sun exposure. These neoplasms are malignant and locally invasive; however, they rarely metastasize.
Pathogenesis
  • BCCs are directly related to life-long sun exposure in susceptible populations, especially those with fair skin. Consequently, BCCs tend to occur in sun-exposed areas, especially the upper half of the face, above the lips.
Morphology
  • Gross Morphology
    • Several different morphologies of BCCs exist, including the nodular, pigmented, superficial, and sclerosing subtypes. The nodular subtype is the most common and its morphology is classically described as a "pearly" papule, plaque, or nodule with shiny rolled borders, depressed center, and the presence of fine telangiectasias.
  • Histological Morphology
    • BCC cells are typically uniform and resemble normal skin basal cells, with large basophilic nuclei. The nodular subtype grows as lobules or buds that invade contiguously into the underlying dermis. The outer-most cells of these basaloid islands are arranged in a radial pattern, with their nuclei pointed toward the center, often referred to as "palisading" periphery.
Clinical Consequences
  • Although [malignant, BCCs rarely metastasize. However, if left untreated these tumors can ulcerate, bleed, and locally invade into underlying tissues, including bones and sinuses, to impressive extents.
Treatment
  • Because metastasis is rare, BCCs can be cured by surgical excision.