What is Mohs surgery?
Mohs micrographic surgery is a highly specialized surgical treatment for skin cancer that provides the highest cure rate compared to traditional techniques.
The original Mohs micrographic surgery procedure was developed by Dr. F. Mohs at the University of Wisconsin. The Mohs technique has been refined over time, although in its basic concept it is still based on three fundamental steps.
What does Mohs surgery consist of?
1. Removal of the tumor tissue: First the affected area is anesthetized, the procedure does not begin until we ensure insensibility throughout the area. Once the anesthesia is completed, the skin layer affected by the tumor is removed.
2. Sophisticated preparation of small portions of the excised tissue for microscopic examination to determine whether or not the tumor has been completely removed.
Hemostasis is performed to prevent bleeding and the wound is provisionally healed while awaiting the laboratory results. During the time waiting for the microscopic analysis the patient can be accompanied, read a magazine or watch television. The approximate duration of this phase is about 30-45 minutes.
Once the lesion has been excised, 100% of the margin is analyzed. For this reason, small portions of tissue must be prepared so that they can be observed under the microscope.
The sections of the portions are frozen in a cryostat properly marked for identification under the microscope.
3. If cancerous cells are detected, the previous procedure is repeated, but only in the affected area, until total healing is achieved.
Once observed under the microscope, they are identified on a graph to guide the existence of malignant cells in case they are found and to be able to remove the tissue where required. The procedure is repeated until the tumor is completely removed.
The defect resulting from the extirpation is “repaired” in the most esthetic way possible, depending on its magnitude, location, skin type, etc. The definitive aspect is achieved a few months after removing the stitches.
Under normal conditions the average number of stages in Mohs surgery is one to three (which usually requires about 2-4 hours until complete healing), although it depends on the particularities of each tumor, if it has received previous treatment and its location.
Where is Mohs surgery performed?
The procedure is slow, sophisticated and requires highly specialized personnel, so there are very few centers in Spain equipped to offer Mohs surgery.
What is done with the remaining wound?
Once the tumor has been completely removed, the best solution to close the wound created by Mohs surgery is decided.
Sometimes it is preferred that it closes on its own, requiring daily dressings for approximately 3-4 weeks.
Other systems consist of closing with sutures directly or by the use of flaps, grafts or cosmetic surgery techniques. The choice depends on the size and location, in any case the patient will be carefully informed about the care required for each particular case.
What is the normal subsequent evolution after Mohs surgery?
Most patients notice some tightness in the wound that decreases with time.
Some degree of itching following wound healing is also normal and benefits from any moisturizer applied on top (simple petroleum jelly is sufficient).
Most tumors affect superficial nerve branches, so it may take a year for normal sensation to return to the area. Until then, tingling and cork sensations may coexist in the area, or alternate between the two.
The tissue surrounding the wound contains much more blood supply than normal for the healing process. This makes the skin pinker and more sensitive to temperature changes. Both the sensitivity and the redness disappear over time.
It must be taken into account that the definitive aspect of a wound must be evaluated one year after the intervention.