3D Mohs Surgery: A New Concept

November 2011 | Volume 10 | Issue 11 | Original Article | 1271 | Copyright © November 2011

Isaac Zilinsky MD,a Perry Robins MD,b Alon Liran MD,a Oren Weissman MD,a Eran Millet MD,a Nimrod Farber MD,a Josef Haik MD,a Eyal Winkler MDa

aThe Haim Sheba Medical Center, Ramat Gan, Israel bProfessor Emeritus, New York University Medical Center, New York, NY


Although Mohs surgery is considered a skin-sparing technique, when dealing with aggressive skin tumor that penetrates the deep tissues, the Mohs surgeon usually sacrifices uninvolved skin. We present our technique of 3D Mohs as a new concept for skinsparing surgery. After raising a skin flap above the residual tumor, Mohs resection was performed on the deep tissues horizontally and simultaneously on the inner plan of the flap vertically. When "clear" borders were achieved, the skin flap was sutured back into place. The results show that the defect was significantly smaller, and the hair on the Mohs-treated vertical flap continue to grow, thus contributing to a more aesthetic outcome. We conclude that careful use of the 3D Mohs technique as we describe spares the healthy uninvolved skin and offers better aesthetic and functional result.

J Drugs Dermatol. 2011;10(11):1271-1274.


The advantages of the Mohs technique are well documented; it allows for complete micrographic margin control,the pathology is interpreted by the surgeon himself, and thus it is more accurate and saves time and money. The defect created after the excision of the lesion is smaller, allowing for easier closure, and, if needed, immediate reconstruction.1,2 It has also been shown that Mohs technique for skin lesions is more cost-effective in the U.S. than conventional surgical excision.3
Mohs is considered a skin-sparing technique, as compared to conventional surgical excision,4-6 but is it a truly skin-sparing surgery in all cases? Unlike breast cancer skin-sparing operations, for example, where the breast is resected while the skin envelope is preserved, in Mohs surgery the skin is excised in some instances even if it is not involved with tumor cells, just to get to a deeper layer (fascia, muscle) were tumor is still present. Still, in most cases, the immediate pathological information gathered by the surgeon allows for the surgical defect to remain as small as possible while still keeping good margin control.7
Every Mohs surgeon, during his years of practice, encounters skin tumors that look rather innocuous and small on the surface but extend over long distances under the skin surface. The excision of these seemingly small lesions can sometimes result in a large skin defect. This type of tumor typically appears on the forehead and scalp where the tumor, usually a morphea type BCC, finds its way to the loose areolar tissue, galea, or temporal fascia and spreads for long distances under the surface, requiring a multi-stage Mohs surgery. The dermis looks normal and in fact is not involved by the tumor, hence every new stage involves scarifying normal skin in order to get to the underlying tumor. A significantly smaller defect could have resulted if the tumor had been safely removed under the surface while maintaining the normal skin above.
We would like to suggest a new technique demonstrating ow to safely extirpate such tumors while preserving the uninvolved overlying skin.
A 72-year-old male underwent a frozen section controlled extirpation of a morphea type BCC on the left side of his forehead nine years before arriving at our clinic. The post-operative defect was down to the bone and included almost all of the left half of the forehead. It was reconstructed with a radial forearm free flap. This was done under general anesthesia by a plastic surgeon, lasted nine hours and required a 12-day hospitalization. When he came to our Mohs clinic for a small BCC removal in a different location, a subcutaneous mass was noticed on the lateral border of the old free flap and a biopsy was taken. The biopsy revealed a recurrent BCC and the patient was scheduled for Mohs surgery. Upon surgery, the tumor was not yet cleared out after eight stages (Figure 1).
The surgery was halted at this stage and the patient was scheduled for another surgical session two days later. On the ninth stage of Mohs resection, the tumor was microscopically tracked spreading along the deep temporal fascia at segments number 4 and 5 (Figure 2, map 9), while the overlying skin was uninvolved. This inflicted great frustration on the surgeon, who was forced to sacrifice normal hair-bearing skin while watching a growing defect on his patient's face.