Micrographic dermatologic surgery (MDS) diplomates: a demographic evaluation and comparison of Medicare case volume.

Micrographic dermatologic surgery (MDS) recently became a board-certified field within dermatology with the first board examination administered in October 2021. To be eligible, dermatologists must have completed a fellowship through the Accreditation Council for Graduate Medical Education (ACGME) or attest to active practice of Mohs micrographic surgery. Attestation of active practice is available from 2021-2025, after which, those sitting for the certifying examination must demonstrate completion of an ACGME-accredited fellowship. This study aimed to compile demographic information on physicians who passed the MDS board certification examination. Medicare Mohs micrographic surgery case volume was compared between fellowship-trained and non-fellowship-trained physicians as well as between members and non-members of Mohs organizations. Names of physicians who passed the examination were accessed on the publicly available American Board of Dermatology website. The Medicare database was used to screen for Mohs surgery case numbers from 2019, and the American College of Mohs Surgery (ACMS) and American Society for Mohs Surgery (ASMS) physician finder tools were used to determine active membership. Physicians not in the Medicare database and those who completed an ACGME-accredited fellowship within the past three years were excluded from case volume analysis. 1673 dermatologists passed the first certifying examination. Medicare Mohs case volumes were compared for 1310 of these physicians. The median number (interquartile range (IQR)) of Mohs surgery cases was significantly higher for physicians who were ACMS/ACGME-fellowship-trained compared to those who were not (370 cases (IQR: 211-560) vs 138 cases (IQR: 37-284), p < 0.001). Members of ACMS and/or ASMS also performed a higher median number of cases compared to non-members (334 cases (IQR: 160-526) vs 95 cases (IQR: 6-246), p < 0.001). Given the 5-year window to take the MDS examination without having completed an ACMS/ACGME-accredited fellowship, more physicians without formal training may choose to become board certified. In addition, less dermatologists may choose to complete an ACMS/ACGME-accredited fellowship since it is not required for board certification. As more dermatologists become board certified in MDS, it may become important to assess for active practice of Mohs surgery and define proficiency metrics.

Treatment of advanced cutaneous squamous cell carcinoma: a Mohs surgery and dermatologic oncology perspective.

Locally advanced or metastatic cutaneous squamous cell carcinoma no longer amenable to surgical resection or primary radiation therapy requires an alternative approach to treatment. Until 2018, management consisted of limited systemic chemotherapies, which carried marginal clinical benefit. The introduction of immunotherapy with anti-PD-1 antibodies resulted in alternative treatment options for advanced cutaneous squamous cell carcinoma with substantial antitumor activity, durable response and acceptable safety profile. The field of immunotherapeutics continues to expand with adjuvant, neoadjuvant and intralesional studies currently in progress. Herein, the authors discuss their approach for the treatment of advanced cutaneous squamous cell carcinoma from the perspective of a Mohs surgeon and a dermatologic oncologist.

Is your patient a candidate for Mohs micrographic surgery?

This guide for family physicians describes the advantages of Mohs surgery and which patients make good candidates for the procedure.

The rule of 10s versus the rule of 2s: High complication rates after conventional excision with postoperative margin assessment of specialty site versus trunk and proximal extremity melanomas.

Specialty site melanomas on the head and neck, hands and feet, genitalia, and pretibial leg have higher rates of surgical complications after conventional excision with postoperative margin assessment (CE-POMA) compared with trunk and proximal extremity melanomas. The rule of 10s describes complication rates after CE-POMA of specialty site melanomas: ∼10% risk for upstaging, ∼10% risk for positive excision margins, ∼10% risk for local recurrence, and ∼10-fold increased likelihood of reconstruction with a flap or graft. Trunk and proximal extremity melanomas encounter these complications at a lower rate, according to the rule of 2s. Mohs micrographic surgery (MMS) with frozen section melanocytic immunostains (MMS-I) and slow Mohs with paraffin sections decrease complications of surgery of specialty site melanomas by detecting upstaging and confirming complete tumor removal with comprehensive microscopic margin assessment before reconstruction. This article reviews information important for counseling melanoma patients about surgical treatment options and for developing consensus guidelines with clear indications for MMS-I or slow Mohs.

The Current State of Mohs Surgery for the Treatment of Melanoma: A Nationwide Cross-Sectional Survey of Mohs Surgeons.

BACKGROUND: The increased use of Mohs micrographic surgery (MMS) to treat melanoma has been accompanied by wide variations in practice patterns and a lack of best practice guidelines. OBJECTIVE: The present study was a nationwide cross-sectional survey of Mohs surgeons to elucidate commonalities and variations in their use of MMS to treat melanoma. MATERIALS AND METHODS: A cross-sectional analysis was performed using survey responses of Mohs surgeons with membership in the American College of Mohs Surgery. RESULTS: A total of 210/513 (40.9%) participants used MMS to treat melanoma of any subtype and 123/210 (58.6%) participants within this group treated invasive T1 melanoma (AJCC Eighth Edition) with MMS. A total of 172/210 (81.9%) participants debulked melanoma in situ (MIS). Average margin size of the first Mohs stage for MIS was 4.96 ± 1.74 mm. A total of 149/210 (71.0%) participants used immunohistochemical stains, with 145/149 (97.3%) using melanoma antigen recognized by T-cells 1 (MART-1) in 96.5% of melanoma cases treated with MMS. CONCLUSION: Over half of surveyed Mohs surgeons treating melanoma with MMS are treating early invasive melanoma with MMS. Most Mohs surgeons treating melanoma with MMS debulk MIS and virtually all use MART-1 when excising invasive melanoma with MMS.

Expert Opinion Regarding Appropriately Timing Dermatological Surgeries in Patients With Recent Myocardial Infarctions.

BACKGROUND: There is limited data on the risk of perioperative myocardial infarctions (MIs) in patients with a recent MI who undergo dermatologic surgeries. OBJECTIVE: Present the recommendations of dermatologic surgeons and cardiologists to determine the safety of dermatologic surgeries after a recent MI. METHODS: An electronic survey was distributed to Mohs surgeons and cardiologists to infer the risk of major adverse cardiac events (MACE) inherent to dermatologic surgery and determine timing of dermatologic surgery in patients with a recent MI. RESULTS: One hundred twenty Mohs surgeons and 30 cardiologists were surveyed. Ninety-seven percent of cardiologists and 87% of Mohs surgeons deemed cutaneous excisions and Mohs micrographic surgery as low-risk procedures with less than one-percent chance of MACE. Seventy-seven percent of cardiologists and 46% of Mohs surgeons stated dermatologic surgery should either not be delayed or be delayed up to 1 month after an MI. Responses between cardiologists and Mohs surgeons did not significantly differ. CONCLUSION: A preponderance of surveyed experts believe that most dermatologic surgeries may be safely performed in patients with a history of an MI within 1 month. The decision to implement urgent dermatologic surgery in patients with a recent MI should account for all clinically significant factors.

Antibiotic Practices in Mohs Micrographic Surgery.

BACKGROUND: Mohs micrographic surgery is a safe procedure with low rates of infection. OBJECTIVE: To establish current antibiotic prescribing practices amongst Mohs surgeons. METHODS AND MATERIALS: 16-question survey sent to American College of Mohs Surgery members. RESULTS: 305 respondents with collectively 7,634+ years of experience. The majority performed outpatient surgery (95.0%) and avoided oral or topical antibiotics for routine cases (67.7% and 62.8%, respectively). Prophylactic antibiotics were routinely prescribed for artificial cardiac valves (69.4%), anogenital surgery (53.0%), wedge excision (42.2%), artificial joints (41.0%), extensive inflammatory skin disease (40.1%), immunosuppression (38.9%), skin grafts (36.4%), leg surgery (34.2%), and nasal flaps (30.1%). A minority consistently swabbed the nares to check for staphylococcus aureus carriage (26.7%) and decolonized carriers prior to surgery (28.0%). CONCLUSION: Disparity exists in antibiotic prescribing practices amongst Mohs surgeons. There may be under-prescription of antibiotics for high risk factors like nasal flaps, wedge excisions, skin grafts, anogenital/lower extremity site, and extensive inflammatory disease. Conversely, there may be over-prescription for prosthetic joints or cardiac valves. Increased guideline awareness may reduce post-operative infections and costs/side effects from antibiotic over-prescription. J Drugs Dermatol. 2020;19(5): doi:10.36849/JDD.2020.4695.

Surgical margins required for basal cell carcinomas treated with Mohs micrographic surgery according to tumor features.

BACKGROUND: Basal cell carcinomas (BCCs) with high-risk features are preferably treated by Mohs micrographic surgery. Studies have shown clinicopathologic characteristics that may predict more stages required for clearance. However, few studies have correlated such factors with the number of millimeters removed per stage. OBJECTIVE: To determine margins necessary for BCC clearance according to tumor features, especially for tumors less than 6 mm, and to suggest initial margins for Mohs micrographic surgery and margins for wide local excision. METHODS: Retrospective analysis of 295 consecutive Mohs micrographic surgeries for primary BCCs. Variables analyzed included patient age, sex, immunostatus, lesion size, location, histologic subtype, borders, stage number, and millimeters excised per stage. RESULTS: BCCs less than 6 mm had a clearance rate of 96% with 3-mm margins. In adjusted multivariable analysis, superficial, micronodular, infiltrative, and morpheaform subtypes were associated with larger margins, whereas clinically well-defined tumors were associated with smaller margins. LIMITATIONS: Because of the limited sample of certain subtypes, a 3-mm margin is better suited for nodular tumors. CONCLUSION: These data help guide initial Mohs micrographic surgery and wide local excision margins required for tumor clearance according to tumor features. Nodular BCCs less than 6 mm may be cleared with 3-mm margins instead of the current 4-mm margin recommendation.

Superficial Basal Cell Cancers Demonstrate Higher Rates of Mixed Histology on High-Risk Anatomical Sites.

BACKGROUND: The Mohs Appropriate Use Criteria (MAUC) have come into question recently regarding the most appropriate treatment for superficial basal cell carcinoma (sBCC). At the heart of this debate is the limited body of evidence describing tumor behavior of sBCC based on clinical factors relevant to the MAUC. OBJECTIVE: To determine whether sBCC is more likely to harbor aggressive subtypes in high-risk anatomical locations and in immunocompromised patients. MATERIALS AND METHODS: A single institution retrospective review produced 133 evaluable Mohs cases performed on sBCC over a 10-year period. All slides from the respective cases were reviewed for the presence of histologic patterns other than known sBCC. Cases were then grouped by both MAUC anatomical zone (H, M, and L) and patient immune status for statistical analysis. RESULTS: A significantly higher rate of mixed histology (MH) was observed when comparing Zone H with Zone L across all patients, healthy patients, and immunocompromised patients. The same was true when comparing Zone M with Zone L for all patients and healthy patients (immunocompromised did not reach significance). CONCLUSION: The authors' data very clearly demonstrate a higher rate of MH in sBCC of the head and neck which provides strong support to the current MAUC scoring.

State of the art of Mohs surgery for rare cutaneous tumors in the Spanish Registry of Mohs Surgery (REGESMOHS).

BACKGROUND: The use of Mohs micrographic surgery (MMS) for rare cutaneous tumors is poorly defined. We aim to describe the demographics, tumor presentation and topography, surgery characteristics and complications of MMS for rare cutaneous tumors in a national registry. METHODS: Prospective cohort study of patients treated with MMS in Spain between July 2013 and June 2018. The inclusion criteria were patients with cutaneous tumors with final diagnosis different from basal cell carcinoma, squamous cell carcinoma, dermatofibrosarcoma protuberans, or any kind of melanoma. RESULTS: Five thousand and ninety patients were recorded in the registry, from which only 73 tumors (1.4%) fulfilled the inclusion criteria: atypical fibroxanthoma (18), microcystic adnexal carcinoma (10), extramammary Paget's disease (7), Merkel cell carcinoma (5), dermatofibroma (4), trichilemmal carcinoma (4), desmoplastic trichoepithelioma (4), sebaceous carcinoma (3), leiomyosarcoma (2), porocarcinoma (2), angiosarcoma (2), trichoblastoma (1), superficial acral fibromyxoma (1), and others (10). No intra-surgery morbidity was registered. Postsurgery complications appeared in six patients (9%) and were considered mild. Median follow-up time was 0.9 years during which three Merkel cell carcinomas, one angiosarcoma, one microcystic adnexal carcinoma, and four others recurred (12.3%). CONCLUSION: This national registry shows that rare cutaneous tumors represent a negligible part of the total MMS performed in our country with a low complication rate.

How Wide Should the Excision Margins for Facial Small Aggressive Basal Cell Carcinoma Be? Experience With 306 Cases.

BACKGROUND: Subclinical extension (SCE) of basal cell carcinomas (BCCs) may be responsible for incomplete resection of the tumor. The aggressive histological patterns (micronodular, infiltrative, and morpheaform) have greater tendencies toward invading surrounding tissues in an irregular pattern. OBJECTIVE: To determine the SCE of small facial aggressive BCCs excised using Mohs micrographic surgery (MMS). MATERIALS AND METHODS: An observational case series study. Data of patients with facial BCCs with aggressive histological patterns, less than or equal to 6 mm in diameter in high risk site (H zone), and 10 mm in intermediate risk site (M zone), treated with MMS between January 2008 and December 2016, were included. RESULTS: This study included 306 histologically confirmed lesions retrieved from 1,196 clinical records reviewed. Median size of tumors was 5.7 mm (interquartile range: 5-6 mm). Resection of the tumors using 2, 3, and 4 mm margins achieves complete excision of the lesion including the subclinical extension area in 73.9%, 94.4%, and 99% of cases, respectively. CONCLUSION: The present study demonstrated that a 4-mm resection margin was enough to eradicate the lesion completely in 99% of cases of primary small facial BCCs with aggressive histological patterns.

Mohs Micrographic Surgery as the Standard of Care for Nail Unit Squamous Cell Carcinoma.

BACKGROUND: There is no established standard of care for treatment of nail unit squamous cell carcinoma (SCC). OBJECTIVE: The aim of the study is to further characterize the clinical characteristics and diagnostic considerations of nail unit SCC and to examine the outcomes of patients with nail unit SCC treated with Mohs micrographic surgery (MMS). MATERIALS AND METHODS: A retrospective review was conducted of patients treated for nail unit SCC with MMS from January 1, 2006, to December 30, 2016. Demographic data were collected along with lesion characteristics, treatment characteristics, and follow-up results. RESULTS: Forty-two cases of nail unit SCC were treated with MMS. Recurrences were observed in 3 patients (7.1%). Recurrent cases were treated with MMS. There were no cases of distant metastases, subsequent recurrence, or death. Two of 3 recurrences occurred in patients with histologic features of verruca vulgaris. CONCLUSION: Mohs micrographic surgery provides an excellent cure rate for the treatment of nail unit SCC. This technique offers the greatest ability to achieve histological clearance while maximizing tissue sparing, thereby reducing unnecessary amputations and patient morbidity.

Frozen-Section Tissue Processing in Mohs Surgery.

BACKGROUND: Mohs micrographic surgery (MMS) is the most reliable tissue-sparing technique in the management of cutaneous malignancies. Although the concept is simple, there is considerable variability in the mapping and processing techniques used by Mohs surgeons and histotechnicians. OBJECTIVE: This review article aims to examine the frozen-section tissue processing techniques. Existing variations will be discussed and pearls offered to optimize the frozen processing technique. METHODS: A PubMed search was performed for publications on methods of tissue processing in MMS. RESULTS: Our review highlights variations in debulking, embedding, processing adipose tissue, cartilage, and wedge resections. We offer pearls on how to avoid false-positive and false-negative margins and discuss advances in immunohistochemistry. CONCLUSION: Our article provides a how-to format on the different stages of tissue processing with pearls and techniques to optimize practice and improve accuracy.

Revised Mohs surgery care guidelines for squamous cell carcinoma in-situ are overdue.

The treatment of cutaneous squamous cell carcinoma in situ by Mohs micrographic surgery is currently deemed as appropriate by the Mohs Appropriate Use Criteria. However, squamous cell carcinoma in situ is a very superficial, indolent, low-risk tumor amenable to destructive and non-surgical treatments. It is uncommon for squamous cell carcinoma in situ to have progressed to invasive malignancy subsequent to definitive management. The suggestion that squamous cell carcinoma in situ on certain anatomic locations has a poorer prognosis is widely assumed but lacks an evidence base. We recommend that most primary squamous cell carcinoma in situ in non-immunosuppressed patients be scored inappropriate or uncertain for Mohs micrographic surgery by the Mohs Appropriate Use Criteria. Multiple other efficacious treatment options exist for managing squamous cell carcinoma in situ, including curettage and cryotherapy, curettage and electrodessication, and topical therapies.