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Though basal cell carcinoma (BCC) is the most common malignancy in the world, its incidence is not recorded in most cancer registries and published figures are probably underestimated. Estimated incidence varies within geographical and ethnic contexts, reaching almost epidemic proportions in some countries. Exposure to UV radiation is a key risk factor, particularly at a young age. The world is increasingly becoming “sun smart,” but there is still a huge lag phase to work through. Alongside an increasing incidence, there are several anatomic subsites in which BCC is becoming increasingly prevalent, such as the pinna, the nose, the upper lip, and the medial eyelid.
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BCC typically spreads slowly and in a predictable manner, and usually does not exhibit satellitosis. Why does BCC behave in such a predictable clinical fashion? One way of thinking about this curiosity is to consider the environmental interplay between cancer cells, immune responses, and other local factors as a complex nonlinear system. In this system, a degree of chaos (unpredictability) may arise in which minute changes within the system result in instability and unpredictable changes in the tumor’s behavior. This chaos may manifest as a surprisingly aggressive outcome such as the occurrence of metastasis in tumors staged to be low risk. Melanoma and breast cancer are two good examples of tumors which are prone to producing chaotic conditions and clinical unpredictability. The conditions which create these less-than-desirable conditions are remarkably rare with BCC, so complete surgical excision is almost invariably curative.
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Given this predictability, BCC is an excellent tumor for dealing with via margin control surgery (MCS) and represents the mainstay of malignancy in the surgical population of a margin control surgeon. The typical presentation is a small manageable tumor, but some cases present quite late and can be large or even massive by the time a patient seeks further assessment. Indications for MCS for BCC can be found in Chap. 4.
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Perhaps surprisingly, there have only been a few prospective studies comparing the efficacy of MCS with wide local excision (WLE) processing. In one large prospective study, nonrecurrent tumors (n = 397) and recurrent tumors (n = 201) were examined in two arms: One treated with excision and WLE processing, and the other treated with MCS. After 10 years of follow-up, a significantly higher local recurrence rate was observed in the group treated with WLE processing. A similarly designed study of 553 BCC showed twice as many excisions had true negative surgical margins in the MCS arm.1-3 Another randomized control study examined 408 facial BCCs and showed a 10-year cumulative probability of recurrence of 4.4% after MCS and 12.2% after WLE processing. For recurrent BCC, cumulative 10-year recurrence probabilities were 3.9% and 13.5% for MCS and WLE processing, respectively.4
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BCC presents in a variety of clinical ...