Tumor Characteristics of Mohs Surgery Patients in Ottawa, Canada Versus Houston, Texas-A Consequence of Access to Care?

BACKGROUND Ontario is one of the most underserved provinces in Canada for providing Mohs micrographic surgery (MMS). A new MMS clinic was opened in Ottawa, Ontario, in June 2009 to help combat the increasing incidence of nonmelanoma skin cancer (NMSC) in this region. OBJECTIVE To prospectively compare MMS cases completed in Ottawa with cases completed in Houston, Texas, and examine the differences in tumor characteristics. MATERIALS AND METHODS The first 150 cases performed in Ottawa were prospectively compared with 150 consecutive cases performed at a Mohs surgery clinic in Houston, Texas. Patient demographics, tumor diagnosis, primary or recurrent disease, tumor dimension, number of surgical stages, defect size, complexity of the procedure, and closure method were compared. RESULTS The average preoperative tumor area was three times as great in Ottawa as in Houston. Almost one entire additional stage was required to clear the tumors treated in Ottawa. Postoperative defects were 87% larger in Ottawa. The number of advanced reconstructive repairs was significantly higher in Ottawa (93%) than Houston (14%). CONCLUSIONS A significantly higher NMSC disease burden and greater surgical complexity was observed in the tumors treated in Ottawa than in Houston.