Mohs Surgery Guide

The Mohs Surgery Treatment Experience: How It Works, Benefits, Risks and What to Expect from the Entire Process

Updated on October 10, 2022, by Don Mehrabi

A skin cancer diagnosis can send anyone into a panic. But if treated promptly and appropriately, patients can jump back into their lives like nothing ever happened.

Mohs micrographic surgery, or “Mohs surgery” for short, is a special procedure that offers the best hope for total recovery from this illness. It eliminates the tumor without disabling or disfiguring the treated body part. And since it is a complex, highly technical procedure, only specially trained board-certified dermatologists can perform it.

Mohs Surgery Procedure
Surgeon and Pathologist—The Dual Roles of the Mohs Surgeon

Patients about to undergo a Mohs procedure usually have a lot of questions about it on top of their cancer-related concerns. This article aims to help unload some of that stress by explaining how the procedure works and its advantages and risks. We also discuss what you can expect throughout the treatment process and the proven ways to stay tumor-free afterward.

What Is Mohs Surgery?

Mohs surgery is a unique skin cancer treatment that removes tumor cells completely but leaves little damage to the surrounding area. It owes its precision to the doctor’s stepwise lesion incision until a thin slice of normal tissue is obtained. It is the gold standard of skin cancer therapy, offering the highest cure rate—meaning the condition has little to no chance of recurring after treatment—and the best cosmetic results.

A Mohs surgeon is a dermatologist highly trained and experienced in using this technique. During the procedure, the dermatologist fulfills the roles of both skin surgeon and pathologist. By doing so, the tumor’s extent is accurately identified, and its extraction is done precisely. 

Mohs surgery is an outpatient procedure performed under local anesthesia, so patients are not sedated and can go home as soon as it is finished. The postop wound is stitched up or allowed to close up on its own, depending on its shape and size. Cosmetic restoration of the treated area is done by surgical reconstruction immediately or days after tumor removal.

The high cost is the main disadvantage of this type of skin cancer surgery. However, since Mohs patients are less likely to see a recurrence and require repeat sessions, the procedure is more cost-efficient than other skin cancer treatments. 

When Is a Mohs Procedure Indicated?

Mohs surgery is indicated for any skin cancer type. It is superior to other skin cancer treatments in the following situations:

  • The tumor has a high risk of local recurrence, e. g. basal cell carcinoma
  • The lesion is in an area where tissue preservation is crucial. Examples are the tip of the nose, the eyelids and the fingers
  • The patient is skin cancer-prone, e. g. those with poor immunity or personal or family history of skin cancer
  • The tumor is likely to spread, e. g. aggressive type or size larger than 2 cm
  • Low-risk tumors
  • Earlier treatments failed

Most patients undergoing the procedure have basal cell carcinoma and squamous cell carcinoma. The cure rates in these cases reach up to 99% for first-time lesions and 90% for recurrent ones. 

Among early-stage melanoma patients, a 98-99% cure rate has been observed. Cancerous mole tissue is normally harder to process than other types. But continuous advancements have made Mohs surgery increasingly valuable in melanoma treatment.

The cure rates for other non-melanoma skin cancers range from 87% to 100%.

 early-stage melanoma
Mohs surgery has a 98-99% cure rate in early-stage melanoma

The following are the contraindications of the Mohs procedure:

  • Health conditions impairing the wound healing process. They include advanced diabetes mellitus, clotting disorders, immunosuppression, poor blood circulation in the problem area, anemia and many others
  • Severe infection
  • Mental health conditions that can make awake patients uncooperative
  • Tumor involvement of vital structures, e. g. bones, nerves, eyes, etc.
  • A history of severe allergy to local anesthesia, latex or any other materials used during surgery
  • Severe cardiovascular or lung disease
  • Advanced age
  • Patient refusal

People with chronic conditions are generally advised to get medical clearance, which lets them know if they can tolerate Mohs surgery. The procedure is not contraindicated in pregnancy. But expectant moms must have no other health problems or be medically cleared before their Mohs appointment.

What Can You Expect During Your Consultation for a Possibly Malignant Skin Lesion?

At BHSkin Dermatology, our specialists treat every patient professionally and compassionately.

People who end up needing a Mohs procedure usually present to our clinic with a suspicious, stubborn lesion. Your Mohs surgeon can spot skin cancer features at first glance, but they will still ask you how the tumor evolved. They will also inquire about your personal and family medical history and lifestyle. If another doctor referred you, the Mohs surgeon might ask for a referral letter and your medical records. 

They will then take a closer look at the lesion. Skin cancer spreads, so the Mohs surgeon will ask your permission to inspect other parts of your body. But don’t worry! Your BHSkin Dermatology specialist shall protect your privacy while completing your physical examination.

When they’re done with their evaluation, the Mohs surgeon will explain their initial impression and give you a plan of action. They will order blood tests and schedule you for a biopsy. If you have a chronic condition, they will advise you to get medical clearance before you undergo any invasive procedure.

Your specialist will explain the benefits and risks of Mohs surgery. While it is the most recommended skin cancer treatment, it is only one of many. If you think you cannot have it for some reason, you may discuss your options with your doctor.

How Do You Prepare for Mohs Surgery?

Preparing for your Mohs session is simple, but this important step helps you avoid potential hassles. 

First, you need to consider a few things before booking your Mohs appointment. The procedure can take several hours to a day, even for seemingly small lesions (see below). Further, you will be advised to avoid vigorous activities for a few weeks after your session. If you have a health condition, you may also need time to secure your medical clearance if your referring physician has not yet issued one. 

Second, you must keep the following in mind days before your treatment:

  • Refrain from smoking and drinking, which disrupt skin repair mechanisms
  • Avoid blood thinners, which prevent proper clotting. If you’re taking aspirin or warfarin for a heart condition or aspirin-like painkillers for joint pains, ask your primary care physician if you can safely skip them for a few days
  • Start taking anti-bruising supplements like arnica and bromelain 2-4 days before your session
Avoid Aspirin After Mohs Surgery
Aspirin interferes with blood clotting and may cause profuse bleeding during and after surgery. Patients on this medication must ask their doctors if they can safely stop taking it for a few days for their Mohs procedure.

Third, remember to do the following before you come in for your appointment:

  • Have a normal breakfast
  • Take your medications, e. g. antihypertensives, as scheduled
  • Shower and wash the treatment area
  • Wear comfortable clothing
  • Avoid jewelry and makeup in the problem area
  • You may bring reading materials or a mobile device to entertain you while you wait
  • You may ask a relative or friend to keep you company

Don’t forget to check in at least 15 minutes before your appointment. This gives you time to fill out some paperwork, e. g. the consent form. The staff will also make sure that your vital signs are normal and stable before your session starts.

What Happens During Mohs Surgery?

Inside the procedure room, the medical staff will confirm your personal information, diagnosis and consent to Mohs surgery at the start of your session. The Mohs surgeon will then prep the target site by cleaning it up, marking it, injecting local anesthesia and covering the surrounding areas with sterile fabric.

The numbing medication will take effect after 30 minutes. You won’t feel any pain when the Mohs surgeon starts cutting away at the cancerous tissue.

After the first stage of the operation, your doctor will temporarily close up the skin, making sure they control any bleeding. At this point, they shall process and examine the tumor tissue. This part can take up to an hour or more, so the medical staff will help you get to our waiting area, where you can wait for the result.

The Mohs surgeon will check the specimen microscopically. If the tissue edges are free of cancer cells, that means they’ve taken out the tumor entirely. They will then come back to finish the surgery. But if the doctor finds cancer cells in the borders, they will make more incisions until they obtain a thin strip of healthy tissue.

Mohs Micrographic Surgery

Once the doctor is sure they have taken out all the cancer cells, they will assess the surgical site. Some postop wounds are stitched up, allowing what we call “healing by primary intention.” But if they are too wide or in a location that cannot be sutured, they are left to heal on their own, a process called “healing by secondary intention.”

Either way, your surgeon will leave a pressure dressing on before sending you home. The pressure dressing must stay in place for at least 24 hours as it helps the surgical wound clot properly.

Big surgical wounds need reconstructive surgery to prevent deformity. Your surgeon can do a Mohs reconstruction right away if the postop wound is not very complex. Otherwise, they will delay it for a few days to get the best cosmetic results.

A single lesion can take an entire day to remove. Multiple tumors will likely require more than one session.

Mohs Surgery Surgical Margin Clearance

What Can You Expect After Your Mohs Procedure?

After Mohs surgery, you should feel more at ease, knowing that you’ve just unloaded a huge burden. At this point, you should be looking forward to your recovery and staying skin cancer-free for good.

Here’s what you need to know:

How Do You Take Care of Your Skin After Mohs Surgery?

One of the most important parts of the post-Mohs period is the aftercare regimen. Your doctor will teach you how to care for your wound properly. The staff will send you home with written instructions.

Generally, you cannot unwrap the bandage for at least 24 hours. However, you may ice the site gently, repeatedly, for 15 minutes every 2-4 hours. Icing during this time controls the inflammation and helps relieve your discomfort.

After 24 hours, you may remove the pressure dressing, take a shower and clean the wound. Wet the bandage a little to soften the crusts. You may then wash the area gently with mild soap and water. Pat it dry with clean gauze. Use a Q-tip to apply a thick layer of petroleum jelly on top. Cover the wound again with a fresh bandage.

You must do this once a day for two weeks or until your follow-up visit. If the bandage gets soaked or dirty, you may replace it with a new one, making sure that the surgical site is clean and amply treated with petroleum jelly.

Icing an injury is best in the first 24 hours when inflammatory processes are most active. Beyond that, you may use a warm compress to relieve soreness.

What Should You Do After Your Mohs Procedure to Help You Heal Quickly?

Besides treating your surgical wound, the following can also help during your recovery:

  • Elevate the treated body part at all times to minimize swelling. For example, if the postop wound is on your face, you must sleep upright in the first few nights after your Mohs session
  • The wound causes mild to moderate pain once the numbing medication wears off. You may take acetaminophen to relieve the discomfort 
  • Continue arnica or bromelain to minimize bruising
  • Infection rarely complicates a Mohs procedure. However, if your doctor prescribes an oral or topical antibiotic, you must use it as instructed

Call your dermatologist or seek medical attention immediately if you encounter problems related to your surgery.

Caring for a Surgical Wound_-01

What Can You Not Do After Mohs Surgery?

Avoiding the following helps you ensure that your surgical wound heals continuously:

  • Vigorous activities, which increase blood pressure and may cause the wound to bleed
  • Moving the treated area, which can reopen the wound
  • The antimicrobial Neosporin, which can irritate the skin and slow down its healing
  • Smoking and drinking
  • Touching the area with your bare hands
  • Scratching or picking at the site
  • Aspirin-like painkillers, which can disrupt clotting processes
  • Sun or UV exposure, which can delay tissue repair and cause uneven pigmentation of healing skin
  • Harsh chemicals, pool water, and makeup, which can irritate the treated area

Also, relax and never lose your cool during this time. Stress releases proinflammatory substances in the body that can delay your recovery.

What to Do After Mohs Surgery

What to Not Do After Mohs Surgery

What Is the Downtime After a Mohs Procedure?

The length of the Mohs recovery period depends on the wound’s size and whether or not it was sutured. 

Sutured wounds are like thin cuts, so the skin surface closes up completely by the second week after surgery. Meanwhile, secondary-intention wounds may take at least three weeks to heal over entirely. However, in both cases, tissue repair in the deeper skin layers can go on for months to years.

Activity restriction for patients with sutured wounds usually takes 1-2 weeks, while it can last three weeks or longer for wide, unsutured ones. Advanced age and some health conditions can prolong the Mohs recovery period.

Healing After Mohs Surgery

How Long After Mohs Surgery Are Stitches Removed?

Sutures must be removed by the second week. Beyond that, the risk of scarring and deformity significantly rises.

What Are the Side Effects of Mohs Surgery?

The most common side effects of any skin surgery are mild to moderate redness, swelling, bruising and pain. These are normal symptoms of inflammation and will go away in a few days, even without treatment. Sensitive patients may ice the treated area and take acetaminophen for symptom relief.

Potential complications include the following:

  • Severe bleeding, bruising, swelling and pain
  • Wound reopening
  • Poor healing
  • Scarring and deformity
  • Infection
  • Hypersensitivity to the surgical materials used

To avoid these unwanted side effects, you must entrust your procedure only to a bona fide Mohs surgeon. Adhering to our pre-treatment preparation and post-treatment care recommendations above is also crucial.

How Important Is It to Follow Up with Your Dermatologist After Your Mohs Procedure?

The post-Mohs follow-up visit is vital because:

  • This is the time when the doctor is supposed to remove your stitches
  • It allows the skin doctor to determine if you’re healing properly or need additional anti-scarring treatment (see below)
  • Some patients may need to combine Mohs surgery with radiotherapy or chemotherapy to kill off occult cancerous cells. Those with multiple lesions will need to come back for another Mohs session. The doctor can discuss such concerns during the follow-up visit

Additionally, your dermatologist may teach you how to do a complete self-skin check on your follow-up. They may also recommend measures to help you ensure the tumor doesn’t return.

You must schedule your follow-up appointment no later than two weeks after your treatment or as advised by your Mohs surgeon.

How Often Does Skin Cancer Come Back After Mohs Surgery?

The odds of recurrence vary for each skin cancer type.

Recurrence is rare in cases of basal cell carcinoma and squamous cell skin cancer, especially if treated early. If detected late, the probability of relapse increases. Tumor recurrence is more likely in the first five years and less beyond that period.

Early-stage melanoma also has a very low chance of reappearance after Mohs surgery. But bigger or widespread lesions raise the odds of relapse and have a more unpredictable course—they can return even decades after removing the first one.

The relapse rates of other non-melanoma skin cancer types vary widely, though Mohs surgery also has high cure rates in these cases.

What Can You Do to Prevent Skin Cancer Recurrence After a Mohs Procedure?

People are born with varying susceptibility to skin cancer. But the following measures are proven to reduce the risk of developing this condition and prevent lesion recurrence and severe illness:

  • Sun protection
  • Avoidance of cancer-causing substances, e. g. in cigarettes, factory exposures, some types of food, etc.
  • Periodic self-skin exams
  • Regular dermatology visits

High-risk patients must perform self-skin checks monthly and see their dermatologists monthly or as needed. Low-risk patients are advised to do both at least once a year.

Mohs Surgery Patients
Skin cancer may occur in families. A family history of skin cancer increases one’s risk of developing the same condition

You may also want to check out our articles on the following related topics:

These articles have further information on the Mohs surgery recovery process, skin cancer risk factors, treatment options and tumor recurrence prevention.

What Kind of Doctors Perform Mohs Surgery?

Only Mohs surgeons can perform Mohs surgery. These medical professionals:

  • Are residency-trained dermatologists certified by the American Board of Dermatology (ABD) and
  • Have undergone an accredited fellowship training program in micrographic surgery and dermatologic oncology (MSDO) or have performed many Mohs procedures in their practice

In 2018, the ABD began conducting the micrographic dermatologic surgery (MDS) certification exam to ensure high performance standards among Mohs surgeons. So when looking for an expert in this field, you must find a fellowship-trained Mohs surgeon or an ABD-certified one.

At BHSkin Dermatology, our Mohs specialists are some of the best in California. You will never go wrong when you trust our skin cancer surgeons.

Frequently Asked Questions

This section shall answer other questions patients commonly ask about the procedure.

Does Mohs Surgery Leave a Big Scar?

As in any other surgical procedure, scarring is possible after Mohs treatment. The risk is higher for patients who have a history of bad scarring or have huge tumors.

However, Mohs surgeons are trained to preserve the appearance and function of the areas they treat. The technique allows them to minimize scarring. Additionally, BHSkin Dermatology specialists may recommend applying Silagen silicone gel on the treated site after suture removal.

How Long Do You Need to Wear a Bandage After a Mohs Procedure?

Bandages protect surgical wounds from trauma that may cause them to reopen. When used together with petroleum jelly, they help speed up wound healing. You need to keep using both on your postop wound for two weeks after your procedure and two weeks after suture removal or as advised by your physician.

Do You Need Plastic Surgery After Mohs Surgery?

That depends on the size of the treated area and the patient’s scarring tendency. Mohs reconstruction is enough to prevent deformity in most cases. But if structures beneath the skin, e. g. nose and ear cartilages, are prominently misaligned, plastic surgery becomes necessary as deep areas are not covered anymore by surgical dermatology.

Can You Drive Home After Your Mohs Appointment?

Patients are not sedated during Mohs surgery, and local anesthesia will not cause drowsiness or whole-body paralysis. Those who wish to drive home after their session are free to do so as long as they do not feel weak or sleepy.

How Long After Mohs Surgery Can You Drink or Smoke?

We generally advise patients to refrain from drinking and smoking one week before a dermatologic procedure and one week after. But abstaining from these habits for good helps you ward off tumor recurrence.

Is Mohs Micrographic Surgery Covered by Insurance?

Yes, Mohs procedures are covered by insurance. But you need to ask your insurance provider about the extent of coverage, which varies between companies and policies.

How Do You Care for a Secondary-Intention Wound Created by Mohs Surgery?

It is similar to caring for a sutured wound. You clean the area thoroughly, pat it dry, apply a fresh, thick layer of petroleum jelly and replace the dressing at least once daily. However, airtight dressings are more often used on such wounds to keep microbes out and lock moisture in. Also, they take more time to heal. 

Skin Cancer Before and After Mohs Surgery
Skin Cancer Before and After Mohs Surgery

The Mohs Micrographic Surgery Experience: The Takeaway

Mohs surgery is the gold standard of skin cancer removal treatments. Its cure rates and esthetic outcomes are superior compared to its alternatives. But only a bona fide Mohs surgeon can perform it because of its complexity.

Patients can avoid complications with good pre-surgical preparation and aftercare. Sun protection, carcinogen avoidance and regular self-skin checks and dermatology visits help prevent relapses and severe illness. Most importantly, to ensure the success of your procedure, trust only a bona fide Mohs surgeon.

Want the Best Chance of Eliminating Skin Cancer? LA’s Top Mohs Surgeons Can Help

Skin cancer treatment can be a scary, uncertain journey. But not when you have LA’s award-winning skin cancer specialists on your side.

At BHSkin Dermatology, we offer a full range of skin cancer treatments, including Mohs surgery. We have helped countless patients get rid of this skin condition for good. Visit us at our Glendale or Encino office or use our teledermatology portal for your initial consultation.

Book your appointment today!


Author: Don Mehrabi

Don Mehrabi, MD, FAAD, is LA’s leading board-certified dermatologist who treats patients, builds the BHSkin clinics, and raises three kids. This blog builds on medical studies combined with Dr. Mehrabi's first-hand experiences from practicing in Encino-Tarzana, Glendale, and online

Get superior skincare from LA's finest dermatologists

Book the type of an appointment that suits you best.


Location map of the following address: 1505 Wilson Terrace.

1505 Wilson Terrace
Suite 240
Glendale, CA 91206

Location map of the following address: 16030 Ventura Blvd.

16030 Ventura Blvd.
Suite 140
Encino, CA 91436

Table with laptop, agenda, cell phone, and some ways representing a person working

Virtual Office Visit
Photo Consultation and Video Consultation

Subscribe To Our Newsletter

If you'd like to be added to our database to receive emails with news about BHSkin products and services, please enter your email address below.