Mohs surgery is considered one of the most effective treatments for many types of skin cancer, including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). The procedure is performed in stages during a single visit, allowing the surgeon to carefully examine the tissue as each layer is removed. This method aims to remove cancerous cells while preserving as much healthy skin as possible
Developed by Dr. Frederic E. Mohs in the 1930s and later refined by Dr. Perry Robins in the 1960s, Mohs micrographic surgery has become an important technique in dermatology. It is often recommended for areas where preserving healthy tissue is important, such as the face, ears, and hands.
Choosing a Qualified Mohs Surgeon
Mohs surgery requires specialized training, as the physician performs multiple roles:
- A surgeon who removes tissue
- A pathologist who examines tissue samples under a microscope
- A surgeon who repairs or closes the wound after the cancer is removed
Benefits of Mohs Surgery
Mohs surgery is often chosen for several reasons:
- It is completed during a single visit, with tissue processing performed on-site using local anaesthesia.
- The technique allows the surgeon to examine nearly all tumour margins under a microscope during the procedure.
- The approach is designed to preserve as much healthy tissue as possible while removing the affected areas.
Stages of Mohs Surgery
Mohs surgery is done in several stages, but all steps are completed during one appointment. Patients typically wait between stages while tissue is analysed.
1. Examination and Preparation
The surgeon examines the biopsy site, marks the area for treatment and positions the patient comfortably. A surgical drape is placed, and local anaesthesia is used to numb the region. Patients remain awake throughout the procedure.
2. Removal of the First Layer
The surgeon removes the visible portion of the skin cancer with a scalpel. Some cancers have extensions beneath the surface, so laboratory assessment is needed to determine whether additional tissue should be removed. The wound is covered while the tissue is processed.
3. Lab Assessment
The removed tissue is colour-coded and carefully mapped. It is then frozen and cut into thin horizontal sections. These sections are examined under a microscope to determine whether any cancer cells remain.
4. Removal of Additional Layers
If cancer cells are still present, the surgeon removes another thin layer of tissue from the specific area where cancer was seen on the microscopic slides. The process of removal and examination is repeated as needed until the tissue shows no remaining cancer cells.
5. Wound Repair
After the cancer has been fully removed, the surgeon determines the best way to manage the wound. Depending on the location and size, the wound may be closed with stitches, allowed to heal naturally or repaired using a skin flap or graft. In some cases, other surgical specialists may assist with reconstruction.
6. Final Steps
If multiple stages are required, the appointment may last several hours. Patients receive detailed instructions on caring for the wound after the procedure, which helps support healing and reduce the risk of complications.
When to Discuss Mohs Surgery With Your Doctor
Every skin cancer case is unique. If you are considering Mohs surgery or want to learn more about whether it may be suitable for you, a discussion with your healthcare provider can help guide the next steps.
