Prevalence of wound complications following Mohs micrographic surgery (MMS): a cross-sectional study of 1000 patients undergoing MMS and wound repair in a UK teaching hospital.

BACKGROUND

Mohs micrographic surgery (MMS) for nonmelanoma skin cancer is often quoted as having an excellent safety profile.

AIM

To determine the complication rate of patients undergoing MMS in a large UK Mohs unit and subdivide complication rates into mild/intermediate and major, and to identify potential risk factors necessitating a clinical intervention.

METHODS

This was a single-centre, cross-sectional study of 1000 consecutive cases of MMS performed with in-house repair. Notes from the postsurgical dressing clinics were reviewed at Visit 1 (Days 7-14) and Visit 2 (approximately Week 6). Based upon the intervention required and effect on cosmetic/functional outcome, complications were classified as minor, intermediate or major. Logistic regression modelling was used to identify risk factors associated with a complication that needed a clinical intervention (i.e. intermediate or major).

RESULTS

In total, 1000 Mohs surgeries were performed on 803 patients, resulting in 1067 excisions. Complication rates in our cohort were low (minor 3.6%, intermediate 3.1% and major 0.8%) Potential risk factors for developing a complication included skin graft (unadjusted OR = 4.89, 95% CI 1.93-12.39; fully adjusted OR = 7.13, 95% CI 2.26-22.45) and patients undergoing surgery on the forehead (unadjusted OR = 3.32, 95% CI 0.95-11.58; fully adjusted OR = 5.34, 95% CI 1.40-20.42). Patients whose wounds were allowed to heal by secondary intention healing (6.8%) exhibited no complications.

CONCLUSION

We advocate that patients should be informed during the consent procedure that less than 1 in every 100 patients (0.75%) undergoing MMS will have a serious adverse event (major complication) affecting their cosmetic or functional outcome.