What to expect from Mohs surgery for basal cell carcinoma

The surgeon numbs the skin around the basal cell carcinoma and removes the visible tumour with a narrow layer of surrounding tissue. That layer is prepared and examined while you wait. If cancer cells remain at an edge, another precisely mapped layer is removed from that area and checked. This process continues until the examined edges are clear.

The resulting wound may be closed with stitches, repaired with a skin flap or graft, or allowed to heal gradually, depending on its size, depth and position. A dressing is applied. Bruising, swelling, tightness, mild bleeding or altered sensation can occur as the wound heals.

Give the surgical team a complete medicine and allergy list, including medicines that affect bleeding, and mention previous skin procedures or conditions that affect healing. Follow instructions about washing, food and medicines. Arrange a calm journey home if advised and avoid planning strenuous tasks immediately afterward.

Keep the dressing in place for the instructed period and wash or re-dress the wound exactly as shown. Protect it from knocks, soaking and unnecessary stretching. Attend dressing or stitch-removal visits, and keep the scar protected from strong sun once the surgeon says the surface has healed.

Contact the surgical team for bleeding that does not stop with firm instructed pressure, pain that is becoming stronger, spreading redness, increasing warmth, pus-like drainage or fever. Urgent care is appropriate for heavy bleeding, breathing difficulty, facial swelling or sudden severe symptoms. Do not wait for a routine appointment if the wound opens widely or the dressing becomes soaked.

Ask why Mohs is suitable for this tumour and site, how the wound may be repaired, which medicines to pause, how to manage the dressing and when stitches are removed. Ask how the scar will be monitored and when a new or changing skin mark should be examined.