Mohs micrographic surgery. A historical perspective.

Excising cancer in successive layers and examining the entire underside of each layer in the microscope by the systematic use of frozen sections ensure eradication of the neoplasm, including its "silent" outgrowths, and this is accomplished with the maximal sparing of normal tissue. Fresh-tissue micrographic surgery is used for most cancers, but the fixed-tissue technique is safer for melanomas because all incisions are made through fixed (killed) tissues, avoiding the danger of disseminating highly transplantable melanoma cells from transecting silent outgrowths or clinically invisible satellites. Although the essential concept was very simple, more than a half century of continuing development was required to bring the method to its present status; further progress is an exciting prospect.