You are in: eMedicine Specialties > Plastic Surgery > SKIN Skin Malignancies, Basal Cell CarcinomaArticle Last Updated: Sep 29, 2006AUTHOR AND EDITOR INFORMATIONAuthor: Maurice Y Nahabedian, MD, FACS, Associate Professor of Plastic Surgery, Department of Plastic and Reconstructive Surgery, Georgetown University Maurice Y Nahabedian is a member of the following medical societies: American College of Surgeons, American Society of Plastic Surgeons, and Plastic Surgery Research Council Editors: Shahin Javaheri, MD, Chief, Department of Plastic Surgery, Martinez Veterans Affairs Outpatient Clinic; Consulting Staff, Advanced Aesthetic Plastic & Reconstructive Surgery; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Wayne Stadelmann, MD, Stadelmann Plastic Surgery, PC; Nicolas (Nick) G Slenkovich, MD, Practice Director, Colorado Plastic Surgery Center at Swedish Medical Center; Jorge I de la Torre, MD, FACS, Professor of Surgery and Physical Medicine and Rehabilitation, Residency Program Director, Division of Plastic Surgery, University of Alabama at Birmingham; Director, Center for Advanced Surgical Aesthetics Author and Editor Disclosure Synonyms and related keywords: BCC, malignancy, skin cancer, malignant lesions, melanoma, squamous cell carcinoma, SCC, skin lesions BASAL CELL CARCINOMA: EVALUATION, DIAGNOSIS, AND MANAGEMENTBasal cell carcinoma is the most common human malignancy. Although this lesion can be significantly invasive and locally destructive, distant metastases are uncommon. Most of these lesions are located on the face and scalp, with the nose, cheek, and periorbital regions the most common sites. Basal cell carcinoma rarely is found on the lip or hand. The increasing incidence of skin cancer has raised concerns about congenital and acquired skin lesions. These lesions range from benign conditions such as a freckle or keratosis to malignant lesions such as basal or squamous cell carcinoma. The incidence of these lesions varies, ranging from 500-1000 cases per 100,000 people. Annually, more than 400,000 people find out they have skin cancer. Etiology is related to a variety of factors that includes skin type, age, and sun exposure. Predisposing factors include individuals with a fair or light complexion, a history of severe sunburns, and poor tanning capability. It is prudent for all physicians to possess a basic understanding and knowledge of the types and characteristics of common skin lesions, because they are frequently asked to evaluate them. This article provides a framework for the surgeon to facilitate the evaluation, diagnosis, and management of cutaneous basal cell carcinoma. For excellent patient education resources, visit eMedicine's Cancer and Tumors Center. Also, see eMedicine's patient education articles Skin Cancer and Skin Biopsy. HISTOPATHOLOGYThe natural history of basal cell carcinoma is that of a slowly growing lesion increasing in size and depth over months and years. Histologically, basal cell carcinomas arise from the basal layer of the epidermis and the pilosebaceous adnexa. The 5 subtypes of basal cell carcinoma include nodular, superficial, micronodular, infiltrating, and morpheaform (ie, sclerosing). The classification into subtypes, first described by Lang and Maize, has strong implications for clinical management. The basosquamous variant is relatively uncommon but more aggressive and does have significant metastatic potential. The morpheaform and infiltrative subtypes are more aggressive in nature with higher recurrence rates. They comprise approximately 10% of basal cell cancers. The infiltrating and morpheaform basal cell carcinomas exhibit islands of tumor extending into the tissue and may exhibit perineural invasion in 3% of patients. This finding helps classify these two histotypes as the most aggressive, with the highest rates of recurrence and positive margins after excision. Nodular and superficial histotypes exhibit the least aggressive growth. Micronodular patterns are intermediate between most and least aggressive. For histological subtypes, the location of occurrence is most often the face, followed by the neck. PRESENTATIONThe most common presentation of basal cell carcinoma is in a Caucasian male older than 60 years. Patients commonly present with multiple coexisting tumors. There is a well-documented association of basal cell carcinoma with previous ionizing radiation and immunosuppression, as observed in patients with organ transplantation. Basal cell carcinoma often is described as a pearly or translucent mass with raised borders and telangiectasias coursing throughout. The lesion may ulcerate, giving rise to the term "rodent ulcer." This classic presentation often is observed in nodular histotypes. Superficial basal cell carcinoma often presents as an erythematous patch or plaque. The lesion may be scaly, with areas of atrophy or scarring, and can be mistaken for eczema or psoriasis. Infiltrating and morpheaform tumors often do not have distinctive characteristics. They may present like scars with indistinct borders. As previously mentioned, the tumor often extends beyond the apparent borders of the lesion, with islands of tumor extending into the tissue. DIAGNOSISAccurate diagnosis of suspicious lesions requires biopsy. Biopsy techniques include shave, punch, incision, and excision. Ensuring that the full thickness of the lesion is incorporated into the specimen is important. Shave biopsy is a safe and simple technique for skin lesions of unknown histotype; it does not require suturing. This technique is recommended for superficial lesions with a low suspicion of malignancy. Incisional, punch, and excisional biopsy allow removal of the full thickness of the specimen, which permits accurate diagnosis. These techniques are recommended if a higher possibility of malignancy exists. TREATMENTElectrodesiccation and curettage Electrodesiccation and curettage is the most common treatment method used by dermatologists. Separate the well-circumscribed tumor from surrounding normal skin and remove any extension of disease with electrodesiccation. Use this method for primary treatment of nodular basal cell carcinoma smaller than 2 cm and superficial basal cell carcinoma of any size. The cure rates for this treatment modality reportedly are 90-98%. Recurrence rates of 50% are reported for tumors wider than 3 cm. Cryotherapy This modality is indicated in the management of primary lesions smaller than 2 cm. Overall cure rates of more than 95% are reported using cryosurgery. Significant scarring, hypopigmentation, and potential injury to adjacent nerves are associated with this treatment. Most significantly, there is no microscopic confirmation of tumor eradication by this method. Cryosurgery is contraindicated in patients with cryoglobulinemia and the more aggressive basal cell carcinomas such as the infiltrating and morpheaform subtypes. It is also contraindicated when scar contracture may cause problems such as periorbital or perioral lesions. Surgical excision Cure rates for surgical excision of basal cell carcinoma are higher than 90%. The size, histotype, and anatomic location of the lesion help determine cure rates. Margins of 2-5 mm are recommended to achieve cure. "The larger the lesion, the wider the margin" is a good general rule. The reconstruction of the defect most often can be achieved by undermining the skin edges and by primary closure. Smaller lesions can be safely excised by general practitioners; patients with larger or more complex lesions are best referred to a plastic surgeon. Mohs micrographic surgery may prove advantageous in certain critical areas, such as the medial and lateral canthal area, perioral area, and in the area of the nasal ala. Cure rates for this technique, which uses horizontal frozen sections of the entire undersurface of the excised tissue, are reportedly 99% for primary lesions and 96% for recurrent lesions. Examine the sections microscopically and plan the extent of the resection accordingly. RECURRENCERecurrence rates are higher in tumors wider than 3 cm or in areas where maximum tissue preservation is required, such as those mentioned above. Basal cell carcinomas with positive margins after primary resection must be re-excised for cure. Histologic features associated with higher recurrence rates include cellular palisading, ulceration, and lymphatic infiltration. Recurrent tumors require larger surgical margins than those used in primary resections. Mohs micrographic technique also is indicated in the management of recurrent lesions. MEDICAL LEGAL CONSIDERATIONS
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