BASAL CELL CARCINOMA

BASAL CELL CARCINOMA - Melissa A. Fischer, MD, MEd
BASICS
DESCRIPTION
• Basal Cell Carcinoma (BCC) is a common malignant tumor of the skin originating from the basal cells of the epidermis and its appendages
• Rarely metastasizes, but capable of local tissue destruction
ALERT
Geriatric Considerations
Greater frequency in geriatric patients (age 55-75 have 100 incidence of age 20)
Pediatric Considerations
Rare in children, but childhood sun exposure important in adult disease
GENERAL PREVENTION
• Sunscreens (though likely more effective for squamous cell carcinoma) (1)[B]
• Hats, long-sleeve shirts
• Avoid tanning and sunburn, especially during childhood
EPIDEMIOLOGY
• Incidence/prevalence in United States: ~900,000 cases/year
• Predominant age: Generally >40, but incidence is increasing in younger populations
• Predominant sex: Males > Female (although incidence is increasing in females)
Incidence
Lifetime risk of caucasion North American: 30%
RISK FACTORS
• Chronic sun exposure (UV radiation)
• Light complexion
• Tendency to sunburn
• Male sex, although increasing risk in women due to lifestyle changes such as tanning beds/salons
• Family history of skin cancer, basal cell nevus syndrome (rare autosomal dominant)
• 3-4 decades after chronic arsenic exposure, 2 decades after therapeutic radiation, chronic immunosuppression
PATHOPHYSIOLOGY
• UV-induced inflammation and Cyclooxygenase activation in skin
• Patched, Drosophila, Homolog of tumor suppressor gene mutations (familial and sporadic)
• Cytochrome P-450 CYP2D6 and glutathione S-transferase detoxifying enzyme gene mutations (especially in truncal BCC)
ASSOCIATED CONDITIONS
• Xeroderma pigmentosum
• Nevoid BCC syndrome

DIAGNOSIS
SIGNS AND SYMPTOMS
• 70% facial, 15% truncal
• Nodular: Most common (60%), presents as pinkish, pearly papule often with telangiectatic vessel and ulceration, usually on face
• Superficial: (30%) light red, scaly papule or plaque with atrophic center, ringed by translucent micropapules, usually on trunk; more common in men
• Morpheaform: (5-10%) firm, smooth, flesh-colored papule with ill-defined borders
• As the nodules enlarge, central ulceration and crusting can occur
History
Exposure to risk factors, family history
TESTS
Diagnostic Procedures/Surgery
Biopsy and pathologic examination mandatory to confirm diagnosis
Pathological Findings
• Nidus of basal cells extending into dermis
• Characteristic cells resemble normal basal cells with large basophilic, oval nuclei.
• Rare mitoses
• Tumor cells arranged in palisades at periphery
DIFFERENTIAL DIAGNOSIS
• Sebaceous hyperplasia
• Epidermal inclusion cyst
• Intradermal nevi (pigmented and nonpigmented)
• Molluscum contagiosum
• Squamous cell carcinoma
• Nummular dermatitis
• Psoriasis
• Melanoma (pigmented lesions)
TREATMENT
PRE-HOSPITAL
Outpatient unless extensive lesion
GENERAL MEASURES
Activity
No restrictions except to avoid overexposure to sun
MEDICATION (DRUGS)
Topical antibiotics after excision for 24-48 hours (optional)
SURGERY
• Generally first choice, specific treatment selection varies with extent and location of lesion, tumor border distinctiveness (2)[A]
• High-risk areas
- Inner canthus, Nasolabial sulcus, Philtrum, Preauricular area, Retroauricular sulcus, Lip, Temple
• Curettage and electrodesiccation
- Nodular lesion 1 cm, in low-risk area, if not deeply invasive
- Requires specialized training and experience in surgical technique
• Excision
- Useful for lesions in high-risk areas, not as dependent on lesion size
- Poor choice if multiple lesions
- Requires appropriate training
• Cryosurgery
- Reserved for small lesions in low-risk area
- Requires specialized training and equipment
- May want pre- and post-treatment biopsies
• Mohs surgery
- The preferred microsurgically controlled surgical treatment for lesions in high-risk area, for recurrent lesion, if there is an aggressive growth pattern
- Requires referral to appropriately trained dermatologic surgeon
Radiation
• Useful for large lesions, very elderly (life expectancy 15 years) or patients who could not tolerate minor surgical procedures
• Also may be used when preservation of local tissue important, such as near lips and eyelids
Medical
5-Fluorouracil (3)[C]
• inhibits thymidylate synthetase interrupting DNA synthesis
• for superficial lesions in low-risk areas
• primary treatment only
• 5% applied b.i.d. for 3-10 weeks Other non-surgical treatments under investigation: Imiquimod, photodynamic therapy, interferon
FOLLOW-UP
PROGNOSIS
• Proper treatment yields 90-95% cure
• Most recurrences happen within 5 years
• Development of new BCCs: Patients (36%) will develop a new lesion within 5 years
COMPLICATIONS
• Local recurrence and spread
• Usually recurrences will appear within 5 years.
• Metastasis (rare, 0.1%), but metastatic disease usually fatal within 8 mos
PATIENT MONITORING
• Every month for 3 months, then twice yearly for 5 years; yearly thereafter
• Increased risk of other skin cancers (4)[C]
REFERENCES
1. Green A, Williams G, Neale R, et al. Daily sunscreen application and betacarotene supplementation in prevention of baseal-cell and squamous-cell carcinomas of the skin: A randomized controlled trial. Lancet. 1999;354: 723.
2. Bath FJ, Bong J, Perkins W, Williams HC. Interventions for basal cell carcinoma of the skin. Cochrane Database Syst Rev. 2003;CD003412.
3. Goette DK. Topical chemotherapy with 5-Fluorouracil. A review. J Am Acad Dermatol. 1981;4:633.
4. Friedma GD, Tekawa IS. Association of basal cell skin cancers with other cancers (United States). Cancers Cause Control. 2000;11:891.
MISCELLANEOUS
Related terms: Basal cell epithelioma; Rodent ulcer