The Mohs micrographic surgery (MMS) is a procedure for primary skin cancers and their recurrence that was originated by Frederic E. Mohs, MD.1 According to the American Medical Association Current Procedural Terminology, "MMS is a technique for the removal of complex or ill-defined skin cancer with histologic examination of 100% of the surgical margins. It is a combination of surgical excision and surgical pathology that requires a single physician to act in 2 integrated but separate and distinct capacities: surgeon and pathologist. The Mohs surgeon removes the tumor tissue and maps and divides the tumor specimen into pieces, and each piece is embedded into an individual tissue block for histopathological examination."2
The most common skin cancers treated by the MMS procedure are basal cell carcinoma, cutaneous squamous cell carcinoma, and nonmalignant skin lesions. Although dermatologic or Mohs surgeons are trained to surgically remove basal cell carcinoma and cutaneous squamous cell carcinoma, plastic surgeons, general surgeons, and other physicians may perform this procedure. With an increase in training, use of the Mohs procedure has increased by 400% from 1995 to 2009,2 and 1 in 4 skin cancers is treated with MMS.2 As the incidence of skin cancer continues to climb, and the field of MMS broadens, predictably more systems-based interprofessional models will emerge. Wound centers that use an interprofessional practice will collaborate in treating potential complications of MMS. An estimated 30% of members of the American College of Mohs Surgery collaborate with physician assistants (PAs) in their practices.3 The number of nurse practitioners involved in this practice also may increase. Tasks most frequently delegated to PAs are presurgical consults and postsurgery follow-ups. After Mohs surgery, PAs are also involved with reconstruction and managing tissue expanders but are rarely involved in taking primary responsibility for excising the Mohs stages and interpreting pathology.3 Mohs procedures typically conclude with a primary closure of the wound and, when the situation dictates, closure by secondary intention. It is not uncommon, however, for wounds with full wound margins, especially in the scalp region, to be closed with tissue expanders, tension sutures, or with tissue flaps in collaboration with a plastic surgeon.
The MMS is a safe and efficient procedure for the amelioration of skin cancers with a low rate of complications. In a recent multicenter prospective cohort study, 20,821 MMS procedures were analyzed, and 149 adverse events (0.72%) were found, including 4 serious events (0.02%), and no deaths were reported. The most common adverse events reported were infections (61.1%), dehiscence and partial- or full-necrosis (20.1%), and bleeding and hematoma (15.4%).4 The concomitant use of anticoagulation accounted for bleeding and wound complications in this cohort.4 A patient-centered postoperative plan is essential and must include family and caregivers especially in patients with advanced age.
Older adult patients often have preexisting comorbidities, including dementia, which may contribute to complications after surgical procedures. In the study previously mentioned, the mean age of patients who experienced serious adverse events was 72.5 years.4 Recent literature about nonagenarians undergoing Mohs procedures attempted to quantify the risk and the postoperative survival for this select group.5-7 In 1 study, the average patient age was 92.3 years6; all patients tolerated the MMS with no deaths within 1 month after surgery. Median survival after surgery was 36.9 months. Tumor characteristics, defect size, number of surgical stages, and closure type did not affect survival, and there was no significant difference in survival based on comorbidities. Instantaneous mortality hazard was highest 2 to 3 years after surgery. This study demonstrates that complexity of surgery (number of Mohs stages, repair) or medical comorbidities do not affect perioperative mortality.
For any procedure, cognitive function and the ability to give consent, understand the procedure, and to follow postoperative instruction must be assessed. This is particularly important in patients with dementia, who may become confused or uncooperative during and after any ambulatory surgical procedure; therefore, preventive measures should be taken. A meticulous care plan for treating the wound and the patient must be followed by the family or other caregivers with regular communication with clinicians responsible for the treatment outcomes.
References