Primary Care Otolaryngology

Chapter 17

much uninvolved tissue as possible. Morpheaform basal cell carcinoma, a sub-type of basal cell carcinoma, has very indistinct borders without the characteristic features of the nodular variant. It is very difficult to excise without the use of real-time, histologic feedback. Therefore, this type of basal cell carcinoma is ideally suited for Mohs’ surgery. Unfortunately, Mohs’ surgery is also costly. Squamous cell carcinoma is more aggressive and may metastasize. It generally requires excision of a five- to six-mm margin to ensure complete removal. Metastasis often occurs in

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Figure 17.2. A large neglected squamous cell carcinoma of the face is present in this individual.

the setting of deep-lesion ulceration and recurrent lesions. Evaluation of the neck nodes and careful follow-up to detect early recurrence or metas- tasis are necessary. Larger tumors are usually treated with wide excision and neck dissection to remove any possible metastases. Malignant Melanoma Cutaneous malignant melanoma is a capricious tumor that affects patients of all ages and has a high mortality rate. There is mounting evidence that sun exposure in childhood is a strong risk factor. It is very common in Australia, and public education in that country has led to the widespread frequent wearing of broad-brimmed hats and the use of sunscreen lotions among 50 percent of adults and children. Both adults and children should be protected from the sun when outside in the summer and in warmer climates. One important point to recognize is that melanomas of the head and neck often display different behavioral tendencies than those in other areas of the body. Melanoma frequently presents as a pigmented lesion, often a mole, that has advanced through radial and vertical growth, color, margin integrity, ulceration, or bleeding. Melanoma begins in the epidermis and then invades the dermis. The depth of invasion is strongly predictive of risk of metastases and ultimately patient survival. The Breslow classification sys- tem includes thin (1-mm invasion or less), intermediate (greater than 1 mm and less than 4 mm), and thick (greater than 4 mm). The risk of met- astatic disease is less than 10 percent with thin lesions but greater than 90

Primary Care Otolaryngology