Basal-cell carcinoma
Basal-cell cancer is a very common skin cancer. It is much more common in fair-skinned individuals with a family history of basal-cell cancer and increases in incidence closer to the equator or at higher altitude. There are approximately 800,000 new cases yearly in the United States alone. Up to 30% of Caucasians develop basal-cell carcinomas in their lifetime. In Canada, the most common skin cancer is basal-cell carcinoma (as much as one third of all cancer diagnoses), affecting 1 in 7 individuals over a lifetime.
Mohs surgery
The clinical quotes for cure rate of Mohs surgery are from 97% to 99.8% after 5 years for newly diagnosed basal-cell cancer (BCC), decreasing to 94% or less for recurrent basal-cell cancer. Radiation oncologists quote cure rates from 90 to 95% for BCCs less than 1 or 2 cm, and 85 to 90% for BCCs larger than 1 or 2 cm. The Surgical excision cure rate varies from 99% for wide margins (4 to 6 mm) and small tumors, to as low as 70% for narrow margins and large tumors. Here the weakness of the procedure is histopathological processing and not the surgeon himself. The fault of the surgeon is failure to understand pathology laboratory methods, and failure to follow the standard of care for adequate surgical margin. Usually, the cure rate using standard bread loafing is very low for narrow surgical margin and a large tumor, and very high for large margins on small tumors.