MOHS SURGERY
Dr. Pablo Umbert, pioneer in the Mohs surgery technique.
“In my professional career, Mohs surgery is the star treatment in my professional activity, which has allowed me to form a school of specialists in this treatment. By bringing together information as a dermatologist, dermatopathologist and dermatologic surgeon, it allows me to be responsible for the whole process, unlike other centers with multiple players, pathologist, surgeon, dermatologist, etc. All this allows me to treat all high-risk locations with very satisfactory results (nose, periorificial, etc.).”
Why choose Dr. Pablo Umbert?
It is a technique of excellence that must be performed by an expert in Mohs surgery.
- Not all those who perform it are dermatologists, pathologists, surgeons, unlike Dr. Pablo Umbert.
- It allows to perform the entire process in a single session:
– Immediate biopsy (Dec) (dic)
– Mohs surgery.
– Study of histopathological sections.
– Aesthetic reconstruction.
– Scar control.
Micrographic Controlled Surgery without interruption (MOHS)
MOHS surgery or CMM has no relation with the classical surgical excision, or the surgical study of the extracted specimen, where the histopathological information may give a false negative 5-10% (20). It also does not relate to the slow MOHS surgery for cutaneous sarcomas, which require several days between the paraffin process and a second intervention if results come out positive.
What is MOHS surgery or CMM
The patient has been previously informed of the different modalities in the treatment of his tumor and the possible risks and complications A list of medications that cannot be taken at least 7 days before the procedure is provided. If any of these medications are needed, the patient must share this with his/her dermatologist to find alternatives.
The patient must have breakfast and a 5 mg valium is administered.
Local anesthesia is given which lasts over 90 minutes. If needed, the sedation can be extended within a safety margin.
The intervention is divided into different stages with 20 minutes time lapses, the necessary time to process the extracted tissue and provide an immediate histological result by an experienced dermatopathologist.
Before the intervention, it is important to review the histological picture/image of the biopsy provided by the micrographic mohs surgeon to observe the histological pattern and facilitate readability during surgery.
Surgical Technique
We eliminate the affected area macroscopically (debulking) with a superficial horizontal cut of the affected area. The three-dimensional image of the basal cell carcinoma helps determine the nature of the invasion of this tumor over healthy tissue.
We initiate the technique two millimeters away from the excised area using a scalpel with an inclination of 45 degrees including epidermis and the rear face of the tumor on a single level/plane to avoid an uneven surface.
The immediate histological examination of the tumor and all the area where the tumor was resting, as if being an open book, allows us to examine all of the histological area without leaving any room to leave behind any malignant cells.
In order to achieve this there has to be a photographic match from the extracted tissue with the perform map where the tumor tissue is deposited, respecting the same orientation. The perimeter of the “piece” is marked with red and black dyes. These dyes, along with the epidermal curb, allow us to locate on a microscopic level any possible malignant cells.
A cut is performed, with a thickness of 5 microns beginning from the back of the piece. Whether being a basal cell or a scaly cell carcinoma, it is introduced into the cryostat, under 20 ° C and stained with a special blue tincture (toluidine), whether it is a basal cell or a scally cell carcinoma.
Final Stage in MOHS surgery or CMM
Histological Interpretation
The biggest difficulty is considering positive histological simulators: Table of false positives or false negatives.
Reconstruction
In large recurrent carcinomas, in high-risk locations, such as in the areas where the facial cranial nerves exit through the bone foramina, a total skin graft is advisable, to best stop a possible recurrence. We use flaps or edge-to-edge in most cases, due to their better aesthetic result and to be sure of the absence of tumor. In tumors such as giant centrofacial keratocanthoma or mutilating carcinomas, it is advisable to delay reconstruction (1-2 months) to easily detect a possible recurrence.
Healing Expectations
Primary Carcinomas
MOHS Surgery 99% success
Recurrent or high risk Carcinomas
Cryosurgery
Laser co2 45% -60
MOHS Surgery 94%