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Chapter 083. Cancer of the Skin (Part 9)

Squamous Cell Carcinoma The natural history of SCC depends on both tumor and host characteristics. Tumors arising on actinically damaged skin have a lower metastatic potential than those on protected surfaces. The metastatic frequency of cutaneous SCC, reported at 0.3–5.2%, occurs most frequently in regional draining lymph nodes. Tumors occurring on the lower lip and ear have metastatic potentials approaching 13 and 11%, respectively. The metastatic potential of SCC arising in scars, chronic ulcerations, and genital or mucosal surfaces is higher. The overall metastatic rate for recurrent tumors may approach 30%. Large, poorly differentiated, deep tumors, with perineural or lymphatic. | Chapter 083. Cancer of the Skin Part 9 Squamous Cell Carcinoma The natural history of SCC depends on both tumor and host characteristics. Tumors arising on actinically damaged skin have a lower metastatic potential than those on protected surfaces. The metastatic frequency of cutaneous SCC reported at 0.3-5.2 occurs most frequently in regional draining lymph nodes. Tumors occurring on the lower lip and ear have metastatic potentials approaching 13 and 11 respectively. The metastatic potential of SCC arising in scars chronic ulcerations and genital or mucosal surfaces is higher. The overall metastatic rate for recurrent tumors may approach 30 . Large poorly differentiated deep tumors with perineural or lymphatic invasion often behave aggressively. Multiple tumors with rapid growth and aggressive behavior can be a therapeutic challenge in immunosuppressed patients. Nonmelanoma Skin Cancer Treatment Basal Cell Carcinoma The most frequently employed treatment modalities for BCC include electrodesiccation and curettage ED C excision cryosurgery radiation therapy laser therapy Mohs micrographic surgery MMS topical 5-fluorouracil and topical immunomodulators. The mode of therapy chosen depends on tumor characteristics patient age medical status preferences of the patient and other factors. ED C remains the method most commonly employed by dermatologists. This method is selected for low-risk tumors e.g. a small primary tumor of a less aggressive subtype in a favorable location . Excision which offers the advantage of histologic control is usually selected for more aggressive tumors or those in high-risk locations or in many instances for aesthetic reasons. Cryosurgery employing liquid nitrogen may be used for certain low-risk tumors but requires specialized equipment cryoprobes to be effective for advanced neoplasms. Radiation therapy while not used as often offers an excellent chance for cure in many cases of BCC. It is useful in patients not considered surgical .