Basal cell carcinoma (BCC) is a slow-growing malignant skin tumor that presents in distinct histological subtypes including nodular, superficial, micronodular, infiltrating, and morpheaform. Nodular BCC is the most common type occurring predominantly on the head and neck regions.
Incidence: the most common skin cancer in Caucasians with approximately 800,000 cases/year diagnosed in the United States
Age: most common in patients over 40 years
Race: most common in Caucasians
Sex: higher incidence in males
Precipitating factors: chronic ultraviolet radiation and fair skin are the most significant predisposing factors. Other factors include ionizing radiation, arsenic exposure, immunosuppression, PUVA, and genetic predisposition.
The most common altered gene in BCC is the PTCH tumor suppressor gene with a resultant altered Hedgehog signaling pathway leading to unregulated cell proliferation and altered cell differentiation. Mutations in the p53 tumor suppressor gene are also frequently observed leading to cellular immortality and resistance to apoptosis.
Pink, erythematous, pearly translucent papule, nodule, or plaque with a rolled border and overlying telangiectasias (Fig. 52.1). Superficial BCC presents as a pink or erythematous thin scaly plaque. The center may become ulcerated and covered by a crust, that is, “rodent ulcer.” Morpheaform BCC exhibits a scar-like appearance with ill-defined borders. They most commonly present in photodistributed areas.
Large BCC on the face. Note the characteristic rolled borders, overlying telangiectasias, and the central ulceration
Dermal melanocytic nevi, sebaceous hyperplasia, squamous cell carcinoma (SCC).
Lobules, nests, or cords of neoplastic basaloid cells with peripheral palisading, clefting, and mucinous stroma.
Locally invasive and slow growing over months and even years. Metastasis is an exceedingly rare occurrence.
KEY CONSULTATIVE QUESTIONS
Excessive sun exposure and other predisposing factors, prior history of BCC or SCC, personal and family history of skin cancer, immunosuppression.
There are multiple methods for treating BCC. Treatment selection should be based upon the age, health, and preferences of the patient after a full discussion of treatment options, risks, and benefits. Given the locally destructive nature of BCC, histological confirmation of complete removal is optimal. Surgical excision and histological evaluation remain the treatment of choice in most cases. Tumors fixed to underlying bone, especially the scalp, merit radiological workup prior to surgical excision or Mohs micrographic surgery. Topical therapies require close follow-up for any evidence of treatment failure or recurrence. Patient education regarding the benefits of sun avoidance, sunscreen use, and regular self-examinations are important ...