INTRODUCTION
Cutaneous squamous cell carcinoma in situ (SCCis), also known as Bowen's disease, is a common intra-epidermal, low-grade malignancy that predominantly occurs on chronically sun-exposed skin, such as the head, neck, and legs.1,2 It often manifests as an asymptomatic, discrete, slow-growing, erythematous, scaly papule or plaque and is considered a precursor to invasive squamous cell carcinoma (SCC),1,3 with a reported incidence of transformation to SCC of 3% to 8%.4 Invasion down to the isthmus and lower follicle occurs in 8.6% of cases with the mean and maximum infiltration depth reported to be 0.32mm and 0.82 mm, respectively.5
There are few studies assessing the demographic, clinical, and surgical outcomes of SCCis treated with Mohs micrographic surgery (MMS) at all anatomic sites6-8 or evaluating results by Mohs Appropriate Use Criteria (MAUC).9 The purpose of this study is to evaluate treatment of SCCis with MMS by MAUC and evaluate whether pretreatment curettage affects the number of stages to achieve clear margins (STCM). This study is a single Mohs surgeon, prospective study evaluating 485 consecutive biopsy-proven SCCis treated with MMS.
There are few studies assessing the demographic, clinical, and surgical outcomes of SCCis treated with Mohs micrographic surgery (MMS) at all anatomic sites6-8 or evaluating results by Mohs Appropriate Use Criteria (MAUC).9 The purpose of this study is to evaluate treatment of SCCis with MMS by MAUC and evaluate whether pretreatment curettage affects the number of stages to achieve clear margins (STCM). This study is a single Mohs surgeon, prospective study evaluating 485 consecutive biopsy-proven SCCis treated with MMS.
MATERIALS AND METHODS
This prospective, single Mohs surgeon, longitudinal cohort study was performed at community-based clinics in northern Texas from April 2018 to May 2021. The Mohs surgeon (HKS) completed a one-year MMS fellowship accredited by the American College of Mohs Surgery. The study protocol conformed to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in its approval by the Baylor Scott & White Research Institutional Review Board. All study data was entered from patients’ operative reports during the procedure. No patient-protected health information was entered into study data records.
All consecutive cutaneous cases of biopsy-proven SCCis treated with MMS were included. Mucosal tumors on both lip and genitalia were excluded. Study parameters included patient age and sex, history of immunosuppression or skin cancer-associated genodermatoses listed in the MAUC,10 treatment date, specific anatomic site, and tumor and final wound (wound) length and width. Width was defined as the largest distance perpendicular to the maximum length. Size was calculated using the formula for a circle or oval: Size = Pi x (length/2) x
All consecutive cutaneous cases of biopsy-proven SCCis treated with MMS were included. Mucosal tumors on both lip and genitalia were excluded. Study parameters included patient age and sex, history of immunosuppression or skin cancer-associated genodermatoses listed in the MAUC,10 treatment date, specific anatomic site, and tumor and final wound (wound) length and width. Width was defined as the largest distance perpendicular to the maximum length. Size was calculated using the formula for a circle or oval: Size = Pi x (length/2) x
