Unplanned incomplete Mohs micrographic surgery

Background: Incomplete Mohs micrographic surgery (MMS) is the cessation of MMS while the tumor margins are known to be still positive. Objective: Our purpose was to examine the factors behind unplanned incomple te MMS and to identify means of avoiding and managing this situation when i t arises. Methods: We performed a retrospective case review examining clinical presen tations, histologic features, and management of incomplete MMS. Results: Fifteen of 10,346 procedures (0.15%) were identified as incomplete MMS. Complete records were available in 14 cases. The age range was 30 to 90 years; the study comprised 10 men and 4 women. The tumors included 9 bas al cell and 4 squamous cell carcinomas and 1 dermatofibrosarcoma protuberan s. The sites involved were nose, medial canthus, ear, scalp, and lower eyel id. Twelve cases dealt with unresectable disease, whereas two patients were unable to tolerate further surgery. Of the unresectable cases, MMS was ter minated because of ongoing multifocal positive skin margins, bony invasion, or extension of tumor to other locations. Surgical defects were repaired, whereas residual disease was managed with a variety of methods. Conclusion: incomplete MMS is a rare problem of either unresectable disease or inability of the patient to tolerate the procedure. Preoperative planni ng may help to identify both subgroups of patients. A multispecialty approa ch to managing these cases is often necessary.