Diagnosis and Management of Nonmelanoma Skin Cancer
Nonmelanoma skin cancer (NMSC) is the most common cancer in the world. Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common types. SCC lesions are more likely to metastasize when compared to BCC, but due to low risk for metastasis, prognosis for NMSC is excellent. Ultraviolet radiation exposure is the main risk factor for developing NMSC. Merkel cell carcinoma and dermatofibrosarcoma protuberans are rare forms of NMSC. The most common BCC lesions types are nodular, superficial, and sclerosing. Nodular BCC typically consists of papular lesions with a pearly border. Superficial BCC lesions are flat or slightly raised, often red to brown. Sclerosing BCC lesions usually have nondiscrete margins. The gross appearance of SCC is that of an erythematous plaque with scale and/or ulceration. The diagnosis of NMSC starts with gross examination, followed by biopsy. Recommended biopsy techniques include punch, shave, and excisional biopsy. Dermatoscopy should also be used to aid in the evaluation of suspected NMSC and other skin cancers, as it greatly enhances the point-of-care diagnosis of skin malignancies. For low-risk lesions, surgical excision is the cornerstone of treatment, although depending on the clinical situation, curettage and electrodessication or non-surgical modalities may be used. Cryotherapy, topical treatments, photodynamic therapy, or radiation treatment can be used to treat BCC and SCC, but cure rates are lower than with surgical excision. High-risk lesions require specialist referral. All patients treated for NMSC should undergo regular complete skin exams, and counseling on the use of sun protection and avoidance.