Mohs micrographic surgery. A Demarcation of the visible tumor and excision with a 1-2 mm margin. The incision is made with the scalpel angled at 45 degrees, allowing for the flattening of surgical margins on the same plane. (B), (1) Surgical specimen. The surgical margins to be examined correspond to all lateral and deep external areas of the fragment. (2) The red arrows indicate the "flattening" of the margins to the same plane. (3) After the fragment is frozen in the cryostat, "horizontal" histological sections are performed, allowing for the analysis of 100% of the lateral and deep margins. The three dark spots correspond to the "roots" of the tumor seen on microscopic examination. (C), The remaining tumor "roots" are excised for further analysis under the microscope. [5]