Eighteen years of experience in Mohs micrographic surgery and conventional excision for nonmelanoma skin cancer treated by a single facial plastic surgeon and pathologist.

[OBJECTIVES/HYPOTHESIS] To determine and compare the efficacy of Mohs micrographic surgery (MMS)- and conventional excision (CE)-confirmed resection of nonmelanoma skin cancers (NMSCs).

[STUDY DESIGN] Retrospective cohort study.

[METHODS] A retrospective cohort study of NMSCs treated in a tertiary referral center by a single facial plastic surgeon and a group of five histopathologists over an 18-year period. The treatment modality was either MMS or CE. The primary outcome measure was recurrence of disease. The secondary outcome measure was the size of resulting surgical excision defect.

[RESULTS] Between 1990 and 2008, 795 patients were treated with MMS and 709 with CE. The median follow-up period for MMS was 24 months and for CE 16 months. Disease recurred in 6/795 and 7/709 patients, respectively (P = .78). Analysis of the resection defects with general linear models adjusted for localization and primary or recurrent disease showed significantly smaller defects after MMS (P = .008).

[CONCLUSIONS] This study demonstrates that: 1) MMS and CE are safe in terms of recurrence rates in NMSCs; 2) MMS can be performed adequately by an experienced facial plastic surgeon in close collaboration with a group of pathologists; and 3) the advantage of MMS is that resection defects can be minimized in important aesthetic and functional areas, such as the nose and eyelid, possibly facilitating the reconstruction.