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Chapter 17
Primary Care Otolaryngology
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
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
Figure 17.2.
A large neglected
squamous cell carcinoma
of the face is present in this individual.