Basal Cell Carcinoma: BCC

Skin cancer ---> Non melanoma skin cancer ---> Basal cell carcinoma

BCC is the most common form of skin cancer. These epithelial- derived tumors can be divided into various subtypes according to clinical appearance, histologic pattern, and biologic behavior. Although BCCs rarely metastasize, they are characterized by slow but relentless and destructive local invasion that results in high morbidity without treatment. The subclinical local invasion may be deep, extensive, and asymmetric, with finger like extensions several centimeters beyond the clinical borders.
The most common subtype of BCC is the well-circumscribed nodular variety. These tumors often present as pearly papules or nodules with telangiectases. They may be pruritic and bleed occasionally. With time, the center ulcerates to create peripheral rolled borders; such ulcerating BCCs are called rodent ulcers. Occasionally, the lesions are deeply pigmented and nodular and can be confused with melanoma. This variant has been called a pigmented BCC. The histologic features of these tumors demonstrate isolated areas of basaloid tumor islands arising from the epidermis with peripheral palisading of nuclei and stromal retraction. In some cases, the BCC has histologic features of squamous metaplasia with keratinization. These tumors have basosquamous differentiation and can become more aggressive and develop regional lymphatic spread.
The most locally aggressive type of BCC is characterized by a diagnostic histopathologic aggressive growth pattern, known as morpheaform, sclerosing, or fibrosing BCC. Clinically, these tumors may be more subclinical, are flat, and appear to be scar like. They have a significant incidence of recurrence because of the isolated, finger like fronds of basal cell tumor cells that may deeply invade the surrounding structures well beyond the clinical margins of the lesion. These small, finger like islands are often missed with standard histologic margin control.
Clinically, superficial BCCs are scaly pink to red lesions. Frequently, they are confused with psoriasis or other eczematous, scaly dermatoses. Although these tumors are usually relatively superficial, extensive superficial subclinical involvement is common. Numerous risk factors are associated with possible extensive subclinical invasion and increased rates of local recurrence for BCC after standard treatment, including surgical excision