This technique is possible thanks to the microscopic monitoring that makes it possible to analyze 100% of the tumor borders of each of the layers, and thus guide the surgeon in the successive tumor persistence until the tumor is completely removed.
The technique consists of performing a systematic and orderly sequence in which a ring of skin around the tumor is removed and analyzed under the microscope, making it possible to observe the entire base of the tissue. This process as a whole is called a “pass” or “stage”. At the end of each pass we will be able to know if the tumor has been completely removed or if, on the contrary, there is tumor persistence in some area. In this case it will be necessary to obtain a new ring of the tumor area, and so on until the tumor is completely removed.
Moreover, this method has the extraordinary additional advantage of not requiring blind safety margins, a fact that allows saving healthy tissue and better postoperative reconstruction possibilities (a determining factor since most skin cancers occur on the face).
Long-term statistics indicate that the Mohs surgery technique is the one that achieves the highest cure rates, despite the fact that patients treated under this modality are usually those with the worst prognosis.