January 14, 2007

Basal Cell Carcinoma

Synonyms and related keywords: BCC, basal cell epithelioma, BCE, basalioma, rodent ulcer, nodular BCC, noduloulcerative BCC, cystic BCC, pigmented BCC, morpheaform BCC, sclerosing BCC, superficial BBC, keratotic BBC, adenoid BBC, infiltrative BCC, Mohs micrographic surgery, Mohs surgery, basal cell cancer, skin cancer, cutaneous malignancy, skin malignancy, cutaneous cancer


Basal cell carcinoma (BCC) is the most common cutaneous malignancy in humans. These tumors typically appear on sun-exposed skin, are slow growing, and rarely metastasize. Neglected tumors can lead to significant local destruction and even disfigurement.

Pathophysiology: Although the exact etiology of BCC is unknown, a well-established relationship exists between BCC and the pilosebaceous unit, as tumors are most often discovered on hair-bearing areas. Tumors are currently believed to arise from pluripotent cells (which have the capacity to form hair), sebaceous glands, and apocrine glands. Tumors usually arise from the epidermis or the outer root sheath of a hair follicle.


Mortality/Morbidity: Although BCC is a malignant neoplasm, it rarely metastasizes. The incidence of metastatic BCC is estimated at less than 0.1%. The most common sites of metastasis are the lymph nodes, the lungs, and the bones. Typically, basal cell tumors enlarge slowly and relentlessly and tend to be locally destructive. Periorbital tumors can invade the orbit, leading to blindness, if diagnosis and treatment are delayed. Perineural invasion can occur, leading to loss of nerve function.

Race: Although BCC is observed in people of all races and skin types, it is most often found in light-skinned individuals; dark-skinned individuals are rarely affected.

Sex: Historically, men are affected twice as often as women. The higher incidence in men is probably due to increased recreational and occupational exposure to the sun, although these differences are becoming less significant with changes in lifestyle.

Age: The likelihood of developing BCC increases with age. With the exception of basal cell nevus syndrome, BCC is rarely found in patients younger than 40 years.


History: Patients often complain of a slowly enlarging lesion that does not heal and that bleeds when traumatized. As tumors most commonly occur on the face, patients often give a history of an acne bump that occasionally bleeds.

Physical: Clinical presentation of BCC varies by type.

Causes: The exact cause of BCC is unknown, although environmental factors that are believed to predispose patients to this disorder include the following:


Malignant Melanoma

Other Problems to be Considered:

Squamous cell carcinoma
Squamous cell carcinoma in situ (Bowen disease)
Actinic keratosis
Sebaceous hyperplasia
Fibrous papule
Desmoplastic trichoepithelioma
Nevi, melanocytic


Lab Studies:

Histologic Findings: Several histologic types of BCC exist, some of which are important because the clinical detection of tumor margins is more difficult with certain histologic types. The characteristic cells of BCC have a large, uniform, oval, nonanaplastic-appearing nucleus with little cytoplasm. The nuclei resemble that of the basal cells of the epidermis, although they have a larger nuclear-to-cytoplasmic ratio and lack intercellular bridges. A mitotic figure is very rarely observed.

The connective tissue stroma surrounding the tumor islands is arranged in parallel bundles and often shows young fibroblasts immediately adjacent to the tumor. Artificial retraction of the stroma from the tumor islands is frequently observed histologically. Additionally, the stroma is often mucinous.

Histologically, BCC is divided into 2 categories: undifferentiated and differentiated. BCC with little or no differentiation is referred to as solid BCC and includes pigmented BCC, superficial BCC, sclerosing BCC, and infiltrative BCC (a histologic subtype). Differentiated BCC often has slight differentiation toward cutaneous appendages, including hair (keratotic BCC), sebaceous glands (BCC with sebaceous differentiation), or tubular glands (adenoid BCC). Noduloulcerative (nodular) BCC usually is differentiated.

Histologic types can be summarized as follows:


Medical Care: In nearly all cases, the recommended treatment modality for BCC is surgery. While newer, nonsurgical therapeutic modalities are future possibilities, currently available medical modalities are considered to be experimental, with cure rates less than that of surgical modalities.

Surgical Care: The goal of therapy for patients with BCC is removal of the tumor with the best possible cosmetic result. By far, surgical modalities are the most studied, most effective, and most used treatments for BCC. The effectiveness of surgical modalities depends heavily on the surgeon's skills; considerable differences in cure rates have been observed among surgeons. Modalities used include electrodesiccation and curettage, excisional surgery, Mohs micrographically controlled surgery, and cryosurgery. Ionizing radiation, although a nonsurgical modality, should be considered in select patients and is discussed below.

Selection of the modality depends on whether the tumor is primary or recurrent, as well as on its location, size, and histologic type. The American Academy of Dermatology has published guidelines regarding the treatment of BCC.

Activity: Instruct patients to avoid sun exposure and other possible predisposing factors (eg, ionizing radiation, arsenic ingestion, tanning beds).


The goal of drug therapy is to eradicate malignant superficial basal cells.

Drug Category: Antineoplastic agents -- The most common chemotherapeutic agent used in superficial BCC is topical 5-fluorouracil.
Drug Name
5-Fluorouracil (Efudex, Carac, Fluoroplex) -- Used topically for the management of superficial BCC. Interferes with DNA synthesis by blocking methylation of deoxyuridylic acid and inhibiting thymidylate synthetase and, subsequently, cell proliferation.
Adult DoseApply bid (Carac may be applied qd), in sufficient amount to cover lesions, for a minimum of 3 wk; only the 5% strength is recommended; therapy might be required for up to 10-12 wk
Pediatric DoseAdminister as in adults
ContraindicationsDocumented hypersensitivity, potentially serious infections
InteractionsNone reported
Pregnancy X - Contraindicated in pregnancy
PrecautionsIncidence of inflammatory reactions can occur with occlusive dressings; porous gauze dressings can be applied for cosmetic reasons without increase in reaction
Drug Name
Imiquimod (Aldara) -- Precise mechanism for superficial BCC is unknown. May increase tumor infiltration by lymphocytes, dendritic cells, and macrophages. Indicated for biopsy-confirmed primary superficial BCC in adults with normal immune systems. Additionally, tumors must not exceed 2 cm in diameter on certain areas of the body. Indicated only when surgical methods are not appropriate.
Adult DoseApply cream to treatment area (including 1 cm of skin surrounding tumor) 5 d/wk at bedtime for 6 wk; leave on for 8 h, then wash area
Pediatric DoseNot established
ContraindicationsDocumented hypersensitivity
InteractionsNone reported
Pregnancy C - Safety for use during pregnancy has not been established.
PrecautionsMedical follow-up is essential to ensure cancer has responded adequately to treatment; may cause redness, swelling, and sore development at application site; may cause itching or burning


Further Outpatient Care:


Patient Education:


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Special Concerns:

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