Histopathologic assessment of depth of follicular invasion of squamous cell carcinoma (SCC) in situ (SCCis): Implications for treatment approach.

BACKGROUND: Squamous cell carcinoma in situ (SCCis) has been reported to involve the hair follicle epithelium. Deep follicular invasion is often cited as a cause of treatment failure. OBJECTIVE: We sought to define the frequency and the depth of hair follicle invasion by SCCis. METHODS: The study included both a retrospective review of intraoperative pathology specimens from 42 SCCis cases treated with Mohs micrographic surgery and a prospective evaluation of serially sectioned SCCis tissue from 12 additional patients. Pathology specimens were analyzed for follicular invasion of SCCis. RESULTS: SCCis invasion of the superficial hair follicle infundibulum was observed in 61.3% to 87.5% of cases in the 2 cohorts, whereas invasion of the isthmus and lower follicle was observed in only 8.3% to 12.5% of cases. In most tumors the depth of follicular invasion was comparable with the thickness of the surrounding epidermis. The maximum observed depth of follicular invasion was 0.82 mm. LIMITATIONS: The study was performed on a limited number of cases referred for surgery at a single institution. CONCLUSIONS: Although SCCis invasion of the upper hair follicle infundibulum is common, deep invasion below the level of the surrounding epidermis is rare. This may have implications for optimal therapy of this condition.

Fast Absorbing Gut Suture versus Cyanoacrylate Tissue Adhesive in the Epidermal Closure of Linear Repairs Following Mohs Micrographic Surgery.

BACKGROUND: Cyanoacrylate topical adhesives and fast absorbing gut sutures are increasingly utilized by dermatologic surgeons as they provide satisfactory surgical outcomes while eliminating an additional patient visit for suture removal. To date, no head-to-head studies have compared the wound healing characteristics of these epidermal closure techniques in the repair of facial wounds after Mohs micrographic surgery. OBJECTIVE: To compare the cosmetic outcome of epidermal closure by cyanoacrylate topical adhesive with fast absorbing gut suture in linear repairs of the face following Mohs micrographic surgery. METHODS: Fourteen patients with wound length greater than 3cm who underwent Mohs micrographic surgery for nonmelanoma skin cancer of the face were enrolled in this randomized right-left comparative study. Following placement of dermal sutures, half of the wound was randomly selected for closure with cyanoacrylate and the contralateral side with fast absorbing gut suture. Using photographs from the three-month postoperative visit, six blinded individuals rated the overall cosmetic outcome. RESULTS: The present study shows no significant difference in cosmetic outcomes between cyanoacrylate and fast absorbing gut suture for closure of linear facial wounds resulting from Mohs micrographic surgery. Cyanoacrylate tissue adhesive may not be as effective in achieving optimal cosmesis for wounds on the forehead or of longer repair lengths. The majority of patients did not have a preference for wound closure techniques, but when a preference was given, cyanoacrylate was significantly favored over sutures. CONCLUSION: Cyanoacrylate tissue adhesive and fast absorbing gut suture both result in comparable aesthetic outcomes for epidermal closure of linear facial wounds following Mohs micrographic surgery. Consideration should be given to factors such as need for eversion, hemostasis, and wound tension when selecting an epidermal wound closure method. (ClinicalTrials.gov, Identifier: NCT01298167, http://clinicaltrials.gov/show/NCT01298167).