Risk factors associated with tumor upstaging in melanomas treated with Mohs micrographic surgery with melanocytic immunohistochemistry.

Background: Mohs micrographic surgery with melanocytic immunohistochemistry (MMS-I) is increasingly utilized for special site melanoma treatment. Yet, frequency and risk factors associated with upstaging of all-stage cutaneous melanomas treated with MMS-I remain undefined. Objective: Determine upstaging frequency and factors associated with tumor upstaging for all-stage melanomas treated with MMS-I. Methods: In this retrospective, single-center case series, all cases of invasive and in situ melanoma treated with MMS-I between 2008 and 2018 were reviewed. Patient and tumor characteristics were recorded and compared between tumors that were and were not upstaged from their initial T stage. Results: Of the 962 melanoma MMS-I cases identified, 44 (4.6%) were upstaged, including 5.6% of in situ and 2.5% of invasive tumors. Risk factors for upstaging included lack of excisional intent at the time of initial biopsy (P < .01), nonlentigo maligna subtype (P = .03), female sex (P = .02), and initial in situ diagnosis (P = .03). Nonstatistically significant characteristics evaluated included patient age (P = .97), initial Breslow depth (P = .18), and biopsy type (P = .24). Limitations: Retrospective study design. Conclusions: All-stage cutaneous melanomas treated with MMS-I are associated with low upstaging rates. Tumor upstaging is associated with lack of excisional intent, female sex, and in situ tumors.

Cost-effectiveness analysis of margin-controlled surgery for vulvar Paget's disease.

Objectives: To determine the cost of two surgical treatment approaches for vulvar Paget's disease and model the cost-effectiveness considering differences in recurrence and reoperation over time. Methods: We assessed cost-effectiveness between excision guided by Mohs micrographic surgery (MMS-E) and traditional wide local excision (WLE). We examined billing data from patients with vulvar Paget's disease who underwent MMS-E (cases, n = 24, 2018-2022) or WLE (controls, n = 64, 1990-2020). We created typical treatment bundles incorporating physician-administered services and facility costs standardized to Medicare reimbursements in 2022 United States Dollars (USD). The primary measure of effectiveness was disease-free years of life. A secondary analysis estimated quality-adjusted life years (QALY). A Markov model simulated treatment pathways over a 10-year time horizon. Transition probabilities were based on institutional recurrence rates (3-year RR 6.7 % for MMS-E vs 34.1 % for WLE). We used a willingness-to-pay threshold of 100,000 USD per QALY. Results: The cost of a single surgical episode was 34,664 USD for MMS-E and 14,969 USD for WLE. In the setting of lower recurrence rates with MMS-E, the incremental cost was 12,789 USD per disease-free year gained. A secondary analysis incorporating QALY showed an incremental cost of 72,820 USD per QALY. Conclusions: MMS-E appears to be a cost-effective treatment for vulvar Paget's disease compared to historic standard of care. Our ability to estimate quality of life gained by avoiding disease recurrence was limited by scant data for this rare condition; thus, future studies incorporating health utility values are needed to facilitate a more comprehensive analysis.

Dermatologic surgeons' approaches to acral lentiginous melanoma: a survey of the American College of Mohs Surgery.

Acral lentiginous melanoma (ALM) is a subtype of melanoma that primarily affects ethnic minorities and is associated with poor outcomes. Racial inequalities in melanoma survival, particularly between Blacks and Whites, have been well documented in the literature. There are limited data on the role of surgical approach to ALM and its contribution to the existing disparities in ALM survival. Thus, this study aimed to investigate the role of surgical approach to ALM among Mohs surgeons. The survey was distributed to members of the American College of Mohs Surgery (ACMS), with 43 physicians completing the survey. The results showed that there was no consensus among Mohs surgeons regarding the surgical approach for ALM, even for advanced stages. 74% respondents performed complete circumferential peripheral and deep margin assessment (CCPDMA) for ALM, including Mohs micrographic surgery (MMS) or en face staged excision. However, barriers such as limited training, low comfort operating on acral sites, and inadequate access to specialized biopsies were reported. Treatment recommendations varied widely regardless of the ALM stage, with no significant differences based on exposure to ALM during training, practice setting, or percent of skin of color patients served. These findings highlight the lack of guidelines and the need for more data on outcomes to support optimal management of ALM. The study emphasizes the importance of addressing healthcare disparities and improving survival outcomes, particularly for ethnic minorities affected by ALM. Consensus guidelines could help standardize treatment approaches and potentially reduce disparities in ALM management.

Mohs surgery for female genital Paget's disease: a prospective observational trial.

BACKGROUND: Extramammary Paget's disease recurs often after traditional surgical excision. Margin-controlled surgery improves the recurrence rate for male genital disease but is less studied for female anatomy. OBJECTIVE: This study aimed to compare surgical and oncologic outcomes of margin-controlled surgery vs traditional surgical excision for female genital Paget's disease. STUDY DESIGN: We conducted a prospective observational trial of patients with vulvar or perianal Paget's disease treated with surgical excision guided by Mohs micrographic surgery between 2018 and 2022. The multidisciplinary protocol consisted of office-based scouting biopsies and modified Mohs surgery followed by surgical excision with wound closure under general anesthesia. Modified Mohs surgery cleared peripheral disease margins using a moat technique with cytokeratin 7 staining. Medial disease margins (the clitoris, urethra, vagina, and anus) were assessed using a hybrid of Mohs surgery and intraoperative frozen sections. Surgical and oncologic outcomes were compared with the outcomes of a retrospective cohort of patients who underwent traditional surgical excision. The primary outcome was 3-year recurrence-free survival. RESULTS: Three-year recurrence-free survival was 93.3% for Mohs-guided excision (n=24; 95% confidence interval, 81.5%-100.0%) compared to 65.9% for traditional excision (n=63; 95% confidence interval, 54.2%-80.0%) (P=.04). The maximum diameter of the excisional specimen was similar between groups (median, 11.3 vs 9.5 cm; P=.17), but complex reconstructive procedures were more common with the Mohs-guided approach (66.7% vs 30.2%; P<.01). Peripheral margin clearance was universally achieved with modified Mohs surgery, but positive medial margins were noted in 9 patients. Reasons included intentional organ sparing and poor performance of intraoperative hematoxylin and eosin frozen sections without cytokeratin 7. Grade 3 or higher postoperative complications were rare (0.0% for Mohs-guided excision vs 2.4% for traditional excision; P=.99). CONCLUSION: Margin control with modified Mohs surgery significantly improved short-term recurrence-free survival after surgical excision for female genital Paget's disease. Use on medial anatomic structures (the clitoris, urethra, vagina, and anus) is challenging, and further optimization is needed for margin control in these areas. Mohs-guided surgical excision requires specialized, collaborative care and may be best accomplished at designated referral centers.

Skin Cancer Associated With Chronic Leg Ulcers in the Population of Olmsted County, Minnesota.

Malignant skin tumors in the setting of chronic leg ulcers (CLUs) are often underdiagnosed which may contribute to treatment delay and poor outcomes. The aims of our study were to determine the incidence and clinical characteristics of skin cancers in leg ulcers in the Olmsted County population from 1995 to 2020. We used the Rochester Epidemiology Project (a collaboration between health care providers) infrastructure to describe this epidemiology, allowing "population-based" research. Electronic medical records of adult patients with International Classification of Diseases diagnosis codes for leg ulcers and skin cancers on the legs were queried. Thirty-seven individuals with skin cancers in nonhealing ulcers were identified. The cumulative incidence of skin cancer over the 25-year period was 37:7864 (0.47%). The overall incidence rate was 470 per 100,000 patients. Eleven (29.7%) men and 26 (70.3%) women were identified with mean age of 77 years. History of venous insufficiency was present in 30 (81.1%) patients and diabetes in 13 (35.1%) patients. Clinical characteristics of CLU with skin cancer included abnormal granulation tissue in 36 (94.7%) and irregular borders in 35 (94.6%) cases. Skin cancers among CLUs included 17 (41.5%) basal cell carcinomas, 17 (41.5%) squamous cell carcinomas, 2 (4.9%) melanomas, 2 (4.9%) porocarcinomas, 1 (2.4%) basosquamous cell carcinoma, and 1 (2.4%) eccrine adenocarcinoma. The apparent association between chronic wounds and subsequent biopsy-proven skin cancer of the same site was primarily observed in elderly patients; malignant transformation of wounds favored basal cell carcinoma and squamous cell carcinoma. This retrospective cohort study further characterizes the association between skin cancers and chronic leg wounds.

Artificial intelligence and frozen section histopathology: A systematic review.

Frozen sections are a useful pathologic tool, but variable image quality may impede the use of artificial intelligence and machine learning in their interpretation. We aimed to identify the current research on machine learning models trained or tested on frozen section images. We searched PubMed and Web of Science for articles presenting new machine learning models published in any year. Eighteen papers met all inclusion criteria. All papers presented at least one novel model trained or tested on frozen section images. Overall, convolutional neural networks tended to have the best performance. When physicians were able to view the output of the model, they tended to perform better than either the model or physicians alone at the tested task. Models trained on frozen sections performed well when tested on other slide preparations, but models trained on only formalin-fixed tissue performed significantly worse across other modalities. This suggests not only that machine learning can be applied to frozen section image processing, but also use of frozen section images may increase model generalizability. Additionally, expert physicians working in concert with artificial intelligence may be the future of frozen section histopathology.

Artificial intelligence for automatic detection of basal cell carcinoma from frozen tissue tangential biopsies.

Evaluation of basal cell carcinoma (BCC) involves tangential biopsies of a suspicious lesion that is sent for frozen sections and evaluated by a Mohs micrographic surgeon. Advances in artificial intelligence (AI) have made possible the development of sophisticated clinical decision support systems to provide real-time feedback to clinicians which could have a role in optimizing the diagnostic workup of BCC. There were 287 annotated whole-slide images of frozen sections from tangential biopsies, of which 121 contained BCC, that were used to train and test an AI pipeline to recognize BCC. Regions of interest were annotated by a senior dermatology resident, experienced dermatopathologist, and experienced Mohs surgeon, with concordance of annotations noted on final review. Final performance metrics included a sensitivity and specificity of 0.73 and 0.88, respectively. Our results on a relatively small dataset suggest the feasibility of developing an AI system to aid in the workup and management of BCC.

Delayed Diagnosis of Retronychia: How Ultrasound Can Nail the Diagnosis in Clinically Subtle Patients.

A 47-year-old man presented to the dermatologic surgery clinic with a 7-month history of a painful, swollen left great toe after minor trauma. Intermittently, the toe became exquisitely tender such that even weight of a blanket exacerbated pain. The patient initially presented to primary care with purulence and pain, but the culture of expressed purulence revealed normal flora. Condition of the patient did not improve despite evaluation by several medical specialists and multiple rounds of topical antifungal and steroid creams, vinegar soaks, and oral antibiotics.

Continuous positive airway pressure device-associated nonhealing ulcer on the nasal dorsum: chondrodermatitis nodularis nasi.

With increasing use of positive airway pressure devices for disordered breathing during sleep, appreciation for potential associated side effects is essential. Chondrodermatitis nodularis nasi is a rare variant of chondrodermatitis nodularis chronic helicis that presents as a nonhealing erosion or ulcer on the nose and can occur in association with chronic use of positive airway pressure devices. We present a case of symptomatic chondrodermatitis nodularis nasi associated with continuous positive airway pressure use, fully responsive to treatment, and propose that this condition is highly underrecognized. Dermatology referral can assist in diagnosis, management, and exclusion of cutaneous malignancy. CITATION: Reinhart JP, Isaq NA, Peters MS, Vidal NY. Continuous positive airway pressure device-associated nonhealing ulcer on the nasal dorsum: chondrodermatitis nodularis nasi. J Clin Sleep Med. 2023;19(6):1157-1159.

Comparing Whole Slide Imaging and Light Microscopy to Identify Tumor in en face Frozen Sections.

OBJECTIVE: To assess accuracy of whole slide imaging (WSI) in the interpretation of permanent and frozen sections in surgical pathology and the identification of tumors in cutaneous en face frozen sections. METHODS: Twenty glass slides containing cutaneous en face frozen sections were selected from twenty cases of keratinocyte carcinomas treated with Mohs micrographic surgery. Ten slides contained tumor and ten did not. A blinded dermatologic surgeon used traditional light microscopy (LM) to assess physical slides for tumor presence and type, while noting the confidence (scale 1-10) and time (min) in making the determination. After a seven-day washout period, the surgeon repeated this process using WSI of the same slides, each de-identified and scanned at 20x using the Aperio AT2 (Leica Biosystems). RESULTS: Percent agreement between LM and WSI was 100%, with Cohen's kappa of 1.0. The average time taken to determine tumor presence was significantly greater using WSI than LM. Similarly, the surgeon was significantly more confident using LM than WSI. CONCLUSION: This proof-of-concept study suggests that diagnostic concordance is excellent between LM and WSI in the evaluation of Mohs frozen sections. However, WSI was cumbersome to use, not ergonomic, and required significantly more time.