Mohs Surgery for Skin Cancer Removal
Close up shot of microscope in an laboratory

Mohs Surgery for Skin Cancer Removal

Mohs surgery is a treatment that can remove various types of skin cancer, including certain types of melanoma. The process involves removing cancerous skin tissue in layers until the cancer is completely gone. Removing skin tissue in layers rather than all at once helps keep the surrounding healthy tissue intact.


Mohs surgery is named after its inventor, Frederic Mohs, who originated the treatment in 1941. Since then, it has become a popular choice for removing skin cancer in a less-invasive way and with less scarring than other procedures.


Mohs surgery is highly effective and usually only requires one treatment. However, the process can be lengthy, so you should be prepared to spend several hours in your doctor’s office. Most people bring a book or other activity to pass the time.


Before the Surgery


Preparing for Mohs surgery is similar to preparing for other minor surgeries. To prepare for your surgery, you may want to:


  • Stop taking medication. Some medications, like blood-thinners or supplements, can increase the risk of bleeding after surgery. Be sure to ask your doctor which medications are safe to take beforehand.


  • Wear loose clothing. This is not necessary, but Mohs surgery can take 3-4 hours or more, so you’ll want to be wearing something comfortable for the duration of your treatment.


What to Expect During Surgery


Mohs surgery is performed under local anesthetic, so you won’t feel any pain while your doctor performs the procedure. 


To start, your doctor will remove the tumor or lesion using a scalpel or small knife. A small amount of tissue from the surrounding area will also be removed and taken to a lab for examination. Your doctor will analyze the tissue from the borders of the tumor to see if any cancer remains. This process allows for minimal damage to healthy tissue.


You may have to wait a while for your doctor the return from the lab, but you’ll be bandaged up in between, so the waiting period won’t be uncomfortable. If your doctor finds the remaining cancer, the process will be repeated until it is completely removed. 


Once all of the cancer has been removed, your doctor will assess the best method for healing the wound. Smaller wounds can be left to heal on their own, while more extensive wounds heal better when closed with stitches.


Sometimes, the wound can be covered with skin from another part of the patient’s body. This can be accomplished by skin grafting or by covering the wound with a piece of the skin next to the wound.


What Type of Cancer Can Mohs Surgery Treat?


  • Basal cell carcinoma—This is the most common form of skin cancer and is predominantly caused by sun exposure. The appearance of basal cell carcinoma varies with each person but commonly consists of small bumps or lesions on the face and neck area.


  • Squamous cell carcinoma—also caused by exposure to UV rays, this type of cancer can be found in most parts of the body and is generally not life-threatening.


  • Melanoma—Melanoma is the most serious and life-threatening form of skin cancer. While Mohs surgery has effectively treated melanoma, it is not always a suitable method for treating this type of skin cancer.


Risks and Complications


Mohs surgery is relatively low-risk, but you may have some minor pain and bruising in the area after the treatment. As the process involves cutting the skin, scarring can occur but tends to be minimal. You may experience mild bleeding in the area after surgery.


Infections after Mohs surgery are uncommon but do occur in rare instances. Symptoms of infection after Mohs surgery include:


  • Redness, tenderness, and swelling in the area
  • Pus or discharge
  • Severe pain


If you develop an infection, consult your doctor. You will likely be prescribed a round of antibiotics.


Complications from Mohs surgery are also rare, but can include:


  • Nerve damage resulting in temporary or permanent numbness in the area
  • Severe pain and itching
  • A large or raised scar




It will take about 4 to 6 weeks for the area to heal after surgery. The size of the wound will impact recovery time, and it is important to avoid infection that can delay healing. 


As with all cancers, there is a risk of re-developing skin cancer after treatment. Mohs surgery has a high success rate and often only requires one treatment, but it’s always a good idea to book a follow-up consultation with your doctor to make sure the cancer has not returned.