Mohs Surgery



Mohs Surgery

Denver’s Dr. Joel Cohen Is Trained and Extensively Experienced in this Sophisticated Skin Cancer Excision Technique

For any patient dealing with skin cancer, the main priorities are a successful diagnosis of the cancer, followed quickly by the successful removal of the cancer cells. To facilitate the most precise diagnosis, the AboutSkin Dermatology team sends slides out to third-party pathologists who are well-known authorities and specialize specifically in pathology of the skin (dermatopathology). Once a diagnosis of a basal cell carcinoma (BCC) or a squamous cell carcinoma (SCC) is made, there are only about 15 dermatologists in Colorado who are FULL fellowship-trained in the cutting-edge procedure of Mohs surgery. Denver’s Dr. Joel Cohen is one such accomplished and well-published physician, trained by the accredited American College of Mohs Surgery, which offers one- to two-year training programs.

Dr. Cohen performs Mohs surgery at our Greenwood Village medical dermatology office in the heart of the Denver Tech Center and has published more than 255 articles (many of which are on skin cancer and reconstruction) and three academic textbooks. He has lectured all over the world on Mohs surgery and reconstruction of skin cancer defects, as well as scar minimization strategies with laser resurfacing.

What Is Mohs Surgery?

Known as “Mohs micrographic surgery,” this highly specialized technique involves Dr. Cohen taking a thin slice of tissue from the treatment area, then closely examining it under a microscope. If he finds cancer cells, he takes another slice—always moving in the direction where the malignancy is detected. In this way, he can work his way precisely to the tumor’s border, stopping only when there are clear margins (meaning no cancer cells are visible).

Mohs surgery differs from the traditional form of excision in a few ways. Traditional excision involves removing a tumor and a generous amount of surrounding tissue. This has long been an established method, but the tissue is literally sectioned like “slices of bread”—so in between the slices, the tissue edges are not visualized, and a tumor can be missed. Mohs surgery takes a narrower margin, as it processes the skin with a much more complete margin analysis (much like looking at a wrapper of a chocolate candy), so Mohs can have a better chance of precisely removing residual cancer than traditional excision. Mohs surgery is thus a more conservative treatment designed to remove the cancer while leaving more of the surrounding healthy tissue intact.

Mohs allows for the viewing of almost 100 percent of the margins of a lesion (much like viewing the entire crust of a pie, including the sides and bottom), which is not possible with traditional excision (where, as noted above, bread-loaf slices of tissue generate a higher risk of missing an intervening tumor between those slices).

In addition, Mohs surgery allows for frozen section microscopic evaluation of excised tissue, accelerating the process so the patient can literally wait in the office for the tissue to be processed.

With a more complete margin analysis and precision, studies show Mohs surgery can have up to a 99-percent cure rate for new cancers (such as basal cell carcinoma), and a 90- to 95- percent cure rate for recurring cancers.

Removing a cancerous tumor is obviously the top goal of any treatment. That said, many patients also desire for the surgery to make as minimal a cosmetic impact as possible, especially if the cancerous lesion is on the face.

Not only does Mohs surgery maximize border analysis and minimize taking adjacent normal skin, it also allows for same-day reconstruction of the skin cancer defect in many cases. Dr. Cohen has extensive training in reconstruction of skin cancer defects through his rigorous FULL fellowship with the American College of Mohs Surgery, and he also rotated through plastic surgery for several months with his internship in general surgery, and subsequently in his residency and fellowship programs.

Dr. Cohen has been performing Mohs surgery in Denver since 2001, treating and reconstructing hundreds of cases each year. Through this experience, Dr. Cohen has lectured regularly at dermatology and skin cancer meetings throughout the world. Dr. Cohen has co-edited a facial skin cancer reconstruction textbook (published by Blackwell-Wiley) and has published many scientific articles/chapters about skin cancer surgery and reconstruction.

Dr. Joel Cohen and Mohs Surgery

Dr. Cohen’s training through the American College of Mohs Surgery was more comprehensive and academic than surgeons who may have trained through societies. Although Mohs surgery training is available in very condensed courses, it is only through a full American College of Mohs Surgery fellowship that a physician is guided through at least 500 cases of supervision over a one- to two-year period.

Dr. Cohen received his extensive training through the American College of Mohs Surgery, studying the removal of skin cancer, histologic evaluation of skin cancer tissue, and reconstruction of the defect in the skin. He is also trained in the most innovative strategies for scar minimization techniques and has published important articles on combination laser treatment of skin cancer scars.





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What our patients say about us


Dr. Cohen is 'a derm's derm' -- his published research and opinions are sought after by other dermatologists obsessed with the latest innovations in cosmetic dermatology, including lasers, neuromodulators, and fillers. He's also trained many of these derms. Dr. Cohen is arguably one of the best in the U.S., though he's not flashy or self promoting --just intensely focused on achieving elegant, successful results. I stumbled into his practice quite by accident, and could not be happier. His PA Christina is also phenomenal.


I am so pleased with the high level of expertise and care I have received from Dr. Cohen, Dr. Ho and his medical assistants Cristina and Emily. From the Mohs surgery, to a multitude of lasers, to skin checks; the doctors  have been extremely conscientious and strive to have a relationship with their patients.  I am thrilled with the results of my cosmetic procedures and surgery.  In addition, They are kind and very humble providers. It truly is an honor to be a patient of Dr. Cohen and to be a valued patient of his medical practice. Truly the best in the country.. and The World. Thank you Dr. Cohen and Dr. Ho and staff!

Chris J

Have been a patient of Dr. Stoler for a long time. She knows me well and takes excellent care of my skin. Also gives good and appropriate advice!

Judy Saul

Dr. Joel Cohen was highly recommended to me by several other dermatologists for his expertise in laser technology. I was not only impressed with the treatment I received from Dr. Cohen, but also his wonderful, highly skilled staff. The entire experience was top notch!

Linda Aibel

This is the BEST dermatology and cosmetic location you will ever find! Truthfully they give all the attention and care anyone could ask for. I’m always blown away at their kindness and their service. Doctor Jade Fettig always takes her time to talk to me, answer any questions and recommend the best treatment. Highly highly recommend AboutSkinDermatology. You will love it there too guaranteed! =)

Roberta Rachkovsky

Dr. Stoler is the best!

Karen Maxwell

I have been a patient of About Skin Dermatology for over 12 years. Everyone that I have ever encountered at this practice has been knowledgeable and very kind. I see both Dr. Ho and Dr. Cohen. My skin has not looked this good in years. My whole family goes to this practice. I would highly recommend About Skin Dermatology.


Dr Fettig was great- took her time with me and answered my questions. She has a nice bedside manner and good sense of humor.

Cindy Wells

I used Dr. Cohen for a Mohs procedure. He is fellowship trained and extremely competent. Dr. Cohen remained involved in my follow up care with a plastic surgeon and was always readily accessible and available to address my concerns. Both he and the office staff are caring and committed to providing the highest level of professional service. I highly recommend Dr. Cohen. I think it’s very nice.

Richard Z

I have been impressed with my Botox treatment from Dr Cohen at AboutSkin Dermatology. He and his staff are incredibly professional and pleasant. Maddie is always flexible and accommodating with my hectic schedule. Dr. Cohen takes time and a genuine interest in his patients. I highly recommend him for any cosmetic procedures.

Kendra W

Dr Stephen Ho is a fantastic dermatologist. He takes the time to listen to concerns and he patiently and thoroughly explains procedures and diagnostics.

Ben Reeves

Dr. Jade Fettig is so kind, thoughtful, and good at what she does. You can tell she really cares about her patients and makes what could be awkward check-ups into comfortable, and pleasant experiences.The office lounge is clean, updated and really relaxing. Absolutely recommend her as a provider!

Carrie Konczal

Dr Rothstein is amazing. Very thorough during her exams and explains everything as she goes along. The staff is great as well! Best physician I have in the Denver area.

Philip Yost

Dr. Joel Cohen is a superbly skilled dermatologist as well as a most caring doctor who always put his patient's best interest first and foremost

Diana Lee