Diagnostic accuracy of autofluorescence-Raman microspectroscopy for surgical margin assessment during Mohs micrographic surgery of basal cell carcinoma.

BACKGROUND: Autofluorescence (AF)-Raman microspectroscopy is a technology that can detect residual basal cell carcinoma (BCC) on the resection margin of fresh, surgically excised tissue specimens. The technology does not require tissue fixation, staining, labelling or sectioning, and provides quantitative diagnosis maps of the surgical margins in 30 min. OBJECTIVES: To determine the accuracy of the AF-Raman instrument in detecting incomplete BCC excisions during Mohs micrographic surgery (MMS), using histology as the reference standard. METHODS: Skin layers from 130 patients undergoing MMS at the Nottingham University Hospitals NHS Trust (September 2022-July 2023) were investigated with the AF-Raman instrument. The layers were measured when fresh, immediately after excision. The AF-Raman results and the intraoperative assessment by Mohs surgeons were compared with a postoperative consensus-derived reference produced by three dermatopathologists. The sensitivity, specificity, and positive and negative predictive values were calculated. The study was registered with ClinicalTrials.gov (NCT03482622). RESULTS: AF-Raman analysis was successfully completed for 125 of 130 layers and, on average, covered 91% of the specimen surface area, with the lowest surface area covered being 87% for the eyelid and the highest being 94% for forehead specimens. The AF-Raman instrument identified positive margins in 24 of 36 BCC-positive cases [67% sensitivity, 95% confidence interval (CI) 49-82] and negative margins in 65 of 89 BCC-negative cases (73% specificity, 95% CI 63-82). Only one of 12 false-negative cases was caused by misclassification by the AF-Raman algorithm. The other 11 false-negatives cases were a result of no valid Raman signal being recorded at the location of the residual BCC due to either occlusion by blood or poor contact between tissue and the cassette window. The intraoperative diagnosis by Mohs surgeons identified positive margins in 31 of 36 BCC-positive cases (86% sensitivity, 95% CI 70-95) and negative margins in 79 of 89 BCC-negative cases (89% specificity, 95% CI 81-95). CONCLUSIONS: The AF-Raman instrument has the potential to provide intraoperative microscopic assessment of surgical margins in BCC surgery. Further improvements are required for tissue processing, to ensure complete coverage of the surgical specimens.

Basal cell carcinoma (BCC) is one of the most common human cancers, occurring mostly on the face and neck. Most BCCs are treated by cutting them out under local anaesthetic. This is routinely done in a hospital by a dermatologist or plastic surgeon. Surgery aims to remove all the cancer leaving the smallest scar possible, but it is often difficult to know how much normal skin to remove. Results from the laboratory often take 1 to 2 weeks to show if the cancer is clear. A technique called 'Mohs' (micrographic surgery) is recommended for these 'high-risk' BCCs. Mohs surgery removes thin layers of skin and investigates them under a microscope while the patient is still in the hospital. This is repeated until all the layers are clear of cancer. Because of the patchy availability of Mohs surgery, many patients with high-risk BCCs are treated by traditional methods that may not be as good as Mohs. We have developed an instrument that scans layers of skin and can quickly detect BCC. The instrument allows surgeons to check each removed skin layer for cancer cells to decide if more layers need to be removed. In this study, the instrument was tested on skin tissue layers from 130 patients who had Mohs surgery at the Nottingham Treatment Centre. The results showed that the instrument can measure skin layers in approximately 30 minutes and identify BCC with a similar accuracy to a Mohs surgeon, but only when the skin layers are prepared properly. With future improvements, the technology might be used to guide Mohs surgery or help surgeons in centres that do not have access to Mohs surgery.

5-Year Follow-Up of a Physician Performance Feedback Report Intervention to Reduce Overuse and Excess Cost: A National Cohort Study.

BACKGROUND: Mohs micrographic surgery efficiently treats skin cancer through staged resection, but surgeons' varying resection rates may lead to higher medical costs. OBJECTIVE: To evaluate the cost savings associated with a quality improvement. MATERIALS AND METHODS: The authors conducted a retrospective cohort study using 100% Medicare fee-for-service claims data to identify the change of mean stages per case for head/neck (HN) and trunk/extremity (TE) lesions before and after the quality improvement intervention from 2016 to 2021. They evaluated surgeon-level change in mean stages per case between the intervention and control groups, as well as the cost savings to Medicare over the same time period. RESULTS: A total of 2,014 surgeons performed Mohs procedures on HN lesions. Among outlier surgeons who were notified, 31 surgeons (94%) for HN and 24 surgeons (89%) for TE reduced their mean stages per case with a median reduction of 0.16 and 0.21 stages, respectively. Reductions were also observed among outlier surgeons who were not notified, reducing their mean stages per case by 0.1 and 0.15 stages, respectively. The associated total 5-year savings after the intervention was 92 million USD. CONCLUSION: The implementation of this physician-led benchmarking model was associated with broad reductions of physician utilization and significant cost savings.

A Systematic Review of the Epidemiology, Clinical Characteristics, Treatment, and Outcomes for Desmoplastic Trichoepithelioma: Underscoring Mohs Micrographic Surgery in Management.

BACKGROUND: Desmoplastic trichoepithelioma (DTE) is an uncommon benign adnexal tumor that histologically may mimic malignant tumors including basal cell carcinoma and microcystic adnexal carcinoma. OBJECTIVE: To present a systematic review of the epidemiology, clinical characteristics, treatment, and outcome data on DTEs, with emphasis on comparing Mohs micrographic surgery (MMS) with other treatments. METHODS: Using the OVID platform, MEDLINE and Embase were searched from inception for studies providing original data on DTEs. RESULTS: A total of 338 cases of DTE from 61 articles were included. No recurrence/persistence (0%) was reported following MMS ( n = 24, mean follow-up of 41.9 months), 13.1% with standard excision ( n = 38, mean follow-up 16.9 months), and 2.1% for electrosurgery/cautery ( n = 49, follow-up 3-72 months). 100% recurrence/persistence for imiquimod ( n = 2) and liquid nitrogen ( n = 4) were identified. In patients who underwent biopsy only, there was a 12.5% recurrence/persistence ( n = 32, mean follow-up 16.5 months). Overall, duration of follow-up varied from 2 months to 6 years for the various management strategies. CONCLUSION: Data are limited regarding DTE outcomes. In this review, surgical modalities, specifically MMS, had the lowest rates of recurrence/persistence compared with other options. Given that most lesions are found on cosmetically sensitive locations, MMS seems to be the optimal management strategy for actively managing DTEs.

Double Immunohistochemical Labelling of PRAME and Melan A in Slow Mohs Biopsy Margin Assessment of Lentigo Maligna and Lentigo Maligna Melanoma.

Introduction: Lentigo maligna (LM) and lentigo maligna melanoma (LMM) predominantly affect the head and neck areas in elderly patients, presenting as challenging ill-defined pigmented lesions with indistinct borders. Surgical margin determination for complete removal remains intricate due to these characteristics. Morphological examination of surgical margins is the key form of determining successful treatment in LM/LMM and underpin the greater margin control provided through the Slow Mohs micrographic surgery (SMMS) approach. Recent assessments have explored the use of immunohistochemistry (IHC) markers, such as Preferentially Expressed Antigen in Melanoma (PRAME), to aid in LM/LMM and margin evaluation, leveraging the selectivity of PRAME labelling in malignant melanocytic neoplasms. Methods: A Novel double-labelling (DL) method incorporating both PRAME and MelanA IHC was employed to further maximise the clinical applicability of PRAME in the assessment of LM/LMM in SMMS biopsies. The evaluation involved 51 samples, comparing the results of the novel DL with respective single-labelling (SL) IHC slides. Results: The findings demonstrated a significant agreement of 96.1% between the DL method and SL slides across the tested samples. The benchmark PRAME SL exhibited a sensitivity of 91.3% in the SMMS specimens and 67.9% in histologically confirmed positive margins. Discussion: This study highlights the utility of PRAME IHC and by extension PRAME DL as an adjunctive tool in the assessment of melanocytic tumours within staged excision margins in SMMS samples.

Autofluorescence Excitation Imaging of Nonmelanoma Skin Cancer for Margin Assessment Before Mohs Micrographic Surgery: A Pilot Study.

BACKGROUND: Autofluorescence photography can detect specific light-tissue interactions and record important pathophysiological changes associated with nonmelanoma skin cancer (NMSC), which has been ascribed to the fluorescence of an aromatic amino acid, tryptophan. OBJECTIVE: To assess the impact of a novel, autofluorescence imaging (AFI) device on margin control for NMSCs before Mohs micrographic surgery (MMS) in an effort to decrease overall operating time. METHODS: Before the initial stage of MMS, NMSCs were measured with a 2-mm margin as standard of care (normal margin). The tumor was then imaged with the AFI device. A 2-mm margin was drawn around the fluorescent area captured by the AFI device and was referred to as the camera margin. The tumor was excised based on the normal margin and evaluated on frozen histological section. RESULTS: Imaging based on the AFI device resulted in appropriate recommendations for margin control in 8 of 11 tumors. Four of these tumors did not fluoresce and demonstrated a lack of tumor residuum on stage I specimen, as anticipated. There were no side effects from the AFI device. CONCLUSION: This is an initial pilot study that supports the use of a novel, noninvasive imaging device to help with margin assessment before MMS. On optimization, this device has potential to extend applicability to surgical excisions for tumors that do not fulfill criteria for MMS.

A deep learning algorithm to detect cutaneous squamous cell carcinoma on frozen sections in Mohs micrographic surgery: A retrospective assessment.

Intraoperative margin analysis is crucial for the successful removal of cutaneous squamous cell carcinomas (cSCC). Artificial intelligence technologies (AI) have previously demonstrated potential for facilitating rapid and complete tumour removal using intraoperative margin assessment for basal cell carcinoma. However, the varied morphologies of cSCC present challenges for AI margin assessment. The aim of this study was to develop and evaluate the accuracy of an AI algorithm for real-time histologic margin analysis of cSCC. To do this, a retrospective cohort study was conducted using frozen cSCC section slides. These slides were scanned and annotated, delineating benign tissue structures, inflammation and tumour to develop an AI algorithm for real-time margin analysis. A convolutional neural network workflow was used to extract histomorphological features predictive of cSCC. This algorithm demonstrated proof of concept for identifying cSCC with high accuracy, highlighting the potential for integration of AI into the surgical workflow. Incorporation of AI algorithms may improve efficiency and completeness of real-time margin assessment for cSCC removal, particularly in cases of moderately and poorly differentiated tumours/neoplasms. Further algorithmic improvement incorporating surrounding tissue context is necessary to remain sensitive to the unique epidermal landscape of well-differentiated tumours, and to map tumours to their original anatomical position/orientation.

Characterizing Gender and Leadership Trends Among Mohs Micrographic Surgery Fellowship Directors.

BACKGROUND: Fellowship directors (FDs) play a key role in shaping Mohs micrographic surgery (MMS). Studies characterizing director trends are lacking and may provide a framework for improving gender diversity. OBJECTIVE: To explore characteristics of FDs and trends in gender of both fellows and FDs over time. MATERIALS AND METHODS: The authors compiled a comprehensive list of FDs and fellows for all Accreditation Council for Graduate Medical Education-accredited Micrographic Surgery & Dermatologic Oncology programs from 1996 to 2023. Publicly available data from various internet sources from February 1, 2023 to May 30, 2023 were used to assess characteristics of MMS FDs. RESULTS: The percentage of female FDs increased from 6% to 25% from 1996 to 2023. Female directors were more likely to select female fellows than male directors ( p = .0002) and had fewer years between fellowship completion and FD appointment (9.1 ± 4.7 years) compared with male directors (13.6 ± 8.8 years; p = .036). H-index, program type, and academic rank were similar between male and female directors. CONCLUSION: Although gender parity among MMS trainees has been achieved, discrepancies remain in the gender composition of FDs. Further studies are required to determine why women are underrepresented as FDs.

MMS hotspots: a cross-sectional comparison of U.S. counties with and without Mohs micrographic surgery.

Healthcare access greatly impacts skin cancer diagnosis and mortality rates. Recognition of current disparities in Mohs micrographic surgery (MMS) access can assist future policy and clinical decisions to correct them. For the years 2014-2018, the CPT codes for MMS (17,311 and 17,313) were counted on a per county level across the United States per the Medicare Centers for Medicare & Medicaid Services (CMS) Medicare Prescriber Database. Any county with 0 MMS CPT codes recorded were classified as "without MMS cases." MMS "hotspots" were identified as counties that possessed a high average number of MMS cases compared to the national average, while also being surrounded by counties that possessed a low average number of MMS cases compared to the national average. Three thousand eighty-four counties in the United States were analyzed; 785 (25%) counties were designated as "with MMS cases" and 2301 (75%) "without MMS cases." There were no significant differences in age, ethnicity distribution, or cost per enrollee between the two designations. 74% of counties with MMS cases were considered urban, while only 25% of those without cases were urban (p < 0.01). The median household income was markedly higher in counties with MMS cases ($71,428 vs. $58,913, p < 0.01). With respect to education, more individuals in counties with MMS cases possessed their General Education Development (GED) (89% vs. 86%, p < 0.01) or a college degree (30% vs. 19%, p < 0.01). Forty-nine counties were considered MMS "hotspots." The density of MMS procedures varies greatly based on geography, maintaining the urban-rural disparity matched by the distribution of MMS surgeons. Additionally, there remains a wide income and educational gap between counties with and without MMS. Identifying MMS hotspots may facilitate further investigation into potential surgical access disparities.

Trends in Mohs surgery fellowship directors.

The purpose of this study is to illustrate demographic trends among Mohs Micrographic Surgery (MMS) Fellowship Directors. Our search was constructed from the 2022 to 2023 Mohs Micrographic Surgery Fellowship Directory on the Accreditation Council for Graduate Medical Education (ACGME) website. Datapoints gathered included: age, sex, residency/fellowship training location, time since training completion until FD appointment, length in FD role, and personal research H-index. We identified 77 FDs, of which all 77 were included in this study. The mean age was 55.5 years; 55 (71.4%) were men and 20 (26.0%) were women. Most of the FDs who completed the survey did not self-report ethnicity or race, so these measures were not included. The top residency institutions that produced the most FDs were Cleveland Clinic (n = 4), Mayo Clinic (n = 4), New York University Medical Center (NYU, n = 4), and University of California-Los Angeles (UCLA, n = 4); the top fellowship institutions were NYU (n = 7), UCLA (n = 5), Cleveland Clinic (n = 4), and Geisinger Medical Center (n = 4). The mean H-index was 15.9, the mean number of peer-reviewed publications was 71, and the mean time from training completion until FD appointment was 10 years. Our results indicate that a majority of FDs are men (71.4%) and that FDs are more likely to have graduated from certain residency and fellowship programs.

Education and Perspectives on the Use of Oral Skin Cancer Chemoprophylaxis: A Cross-Sectional Survey of Current Fellows in Mohs Micrographic Surgery & Dermatologic Oncology.

BACKGROUND: According to the curriculum guidelines of the Accreditation Council of Graduate Medical Education and the American Board of Dermatology, Mohs micrographic surgery & dermatologic oncology (MSDO) fellows must demonstrate competency in the use of oral skin cancer chemoprophylaxis. The current level of education in this area is unknown. OBJECTIVE: To characterize oral skin cancer chemoprophylaxis education for acitretin and nicotinamide among current MSDO fellows and to compare the clinical indications felt most appropriate for prescribing to a previously published expert consensus. METHODS: An electronic survey was distributed to all active MSDO fellows by the American College of Mohs Surgery. RESULTS: Responses were received from 63 (69.2%) MSDO fellows. Twenty (31.7%) and 37 (58.7%) fellows reported receiving fellowship training on acitretin and nicotinamide, respectively. Fifty-seven (90.5%) intend to prescribe chemoprophylaxis after training. Sixteen (28.1%) and 43 (75.4%) report feeling very comfortable prescribing acitretin and nicotinamide, respectively. Fellow concordance with a previously published expert consensus opinion on appropriate prescribing indications is variable. Forty-one (65.1%) indicated that additional education would increase the likelihood to prescribe after training. CONCLUSION: Although most MSDO fellows intend to prescribe oral skin cancer chemoprophylaxis, a standardized curriculum may promote increased use and concordance with expert consensus recommendations.

Retrospective analysis shows the cost of Mohs surgery decreases when adjusted for medical inflation.

BACKGROUND: Mohs surgery (MS) is the gold standard for treating nonmelanoma skin cancers in cosmetically sensitive areas. OBJECTIVE: To investigate MS costs over time when adjusting for medical inflation while considering the perspective of patients, payers, and health care systems. METHODS: A retrospective claim analysis using data from the International Business Machines MarketScan Commercial Claims and Encounters Database from 2007 through 2019 was performed. A query of the database for any instance of a MS-specific Current Procedural Terminology (CPT) code in adults (17311, 17312, 17313, 17314, and 17315) was conducted. Aggregate data per claim regarding coinsurance, total cost, deductible, copay, and insurance payout were provided for each CPT code annually. RESULTS: The total adjusted cost per claim decreased significantly (P < .001) for 4 of the 5 MS-specific CPT codes between 2007 and 2019: 17311 (-25%), 17312 (-15%), 17313 (-25%), and 17314 (-18%). The patient's adjusted out-of-pocket expense increased significantly (P < .0001) for 4 of the 5 MS-specific CPT codes: 17311 (33%), 17312 (45%), 17313 (34%), and 17314 (43%). CONCLUSION: Among the 4 most used MS-specific CPT codes (17311, 17312, 17313, and 17314), the total cost per claim decreased and the patient's out-of-pocket expense increased from 2007 to 2019.

A Cost Analysis of Mohs and Total Surgical Excision: A Retrospective Review of Skin Cancer Treatments.

PURPOSE: Skin cancer risk is elevated in veterans, Whites, and males older than 50 years, who comprise the majority of patients at the Miami VA healthcare system.Treatments include total surgical excision (TSE) with frozen section or permanent pathology, and Mohs surgery. Our protocol consists of Mohs procedures performed offsite followed by reconstruction at the VA. This retrospective study examines the cost difference between TSE and Mohs surgery. METHODS: A retrospective chart review was performed of VA patients who underwent TSE or Mohs surgery between 2017 and 2019. Patients younger than 18 or those without malignancy on final pathology were excluded. Patients were subdivided into TSE versus Mohs. Cost per operating room minute was determined using published data for similar institutions. Pathology costs were estimated using institution specific Medicare data. T test was performed using SPSS. RESULTS: Of 130 patients identified, 82 underwent TSE and 48 underwent Mohs with reconstruction. Cost per operating room minute for inpatient government-owned facilities was $37.94. A flat fee of $1400 for the Mohs surgery was the contracted rate with the offsite institution. Average cost of Mohs surgery with reconstruction was $3534.12. Average cost of TSE with pathology was $2643.85. Total surgical excision was significantly more cost efficient than Mohs with reconstruction (P < 0.01). CONCLUSIONS: At our institution, TSE seems more cost effective than Mohs with subsequent reconstruction. While these are generalized costs, and data specific to our institution, cost efficiency is an important consideration in improving the value of care for VA patients.

Trends in sex and ethnicity among U.S. dermatopathology and Mohs surgery trainees: 2011-2021.

Dermatology has been cited as the second-least racially diverse medical specialty in the United States. In the last decade, the American Academy of Dermatology (AAD), the Skin of Color Society (SOCS), the Dermatology Section of the National Medical Association (NMA), and other stakeholders have made significant efforts to increase diversity in dermatology. This study aims to explore the potential impact of these efforts by analyzing sex and ethnic trends in ACGME-accredited dermatology fellowships; Mohs surgery, and dermatopathology, using data from 2011-2021. Our findings reveal that over the last decade, significant strides to increase sex diversity within dermatology have led to a growing number of female resident trainees (62%). This trend is also reflected in Mohs surgery (50%) and dermatopathology (52%) fellowships. In addition, the proportion of Underrepresented in medicine (URiM) fellowship trainees has also increased significantly over the last decade, with a now similar proportion of URiM trainees between dermatology residency, Mohs surgery, and dermatopathology.

Diversifying the Mohs Workforce: Understanding Barriers of Applicants to Mohs Micrographic Surgery Fellowship.

BACKGROUND: The population of the United States is becoming increasingly diverse, yet dermatology, especially Mohs micrographic surgery (MMS), lags behind. OBJECTIVE: This survey study investigates perceived barriers of underrepresented groups in medicine (URM) who are pursuing fellowship in Mohs micrographic surgery and dermatologic oncology (MSDO). METHODS AND MATERIALS: An IRB-approved survey was distributed electronically to accredited dermatology residencies between December 2020 and April 2021. RESULTS: One hundred and thirty-three dermatology residents responded to the survey and of the participants, 21% identified as a URM. There was no significant difference in those interested in applying for MSDO fellowship between URMs and non-URMs. URMs rated the following factors significantly higher when deciding to pursue MSDO fellowship: lack of perceived diversity in target patient population (mean 3.61, SD 1.66), race/ethnicity/gender of past MSDO fellows (mean 3.25, SD 1.71), perceived attitudes of MSDO fellowships towards an applicant’s race or ethnicity (mean 3.25, 1.65 SD), and lack of diversity of trainees and faculty in MMS (mean 3.61, SD 1.47). CONCLUSION: This study is one of the first to evaluate perceived barriers to diversifying the MMS workforce. The perceived barriers we have identified are complex and require concerted efforts for improvement. J Drugs Dermatol. 2023;22(5): doi:10.36849/JDD.7083.