Mohs Micrographic Surgery at Challenging Anatomical Sites

Mohs micrographic surgery challenges and new technologies to optimize care of cutaneous malignancies of the ear

Cutaneous malignancies affecting the ear, exacerbated by extensive ultraviolet (UV) exposure, pose intricate challenges owing to the organ's complex anatomy. This article investigates how the anatomy contributes to late-stage diagnoses and ensuing complexities in surgical interventions. Mohs Micrographic Surgery (MMS), acknowledged as the gold standard for treating most cutaneous malignancies of the ear, ensures superior margin control and cure rates. However, the ear's intricacy necessitates careful consideration of tissue availability and aesthetic outcomes. The manuscript explores new technologies like Reflectance Confocal Microscopy (RCM), Optical Coherence Tomography (OCT), High-Frequency, High-Resolution Ultrasound (HFHRUS), and Raman spectroscopy (RS). These technologies hold the promise of enhancing diagnostic accuracy and providing real-time visualization of excised tissue, thereby improving tumor margin assessments. Dermoscopy continues to be a valuable non-invasive tool for identifying malignant lesions. Staining methods in Mohs surgery are discussed, emphasizing hematoxylin and eosin (H&E) as the gold standard for evaluating tumor margins. Toluidine blue is explored for potential applications in assessing basal cell carcinomas (BCC), and immunohistochemical staining is considered for detecting proteins associated with specific malignancies. As MMS and imaging technologies advance, a thorough evaluation of their practicality, cost-effectiveness, and benefits becomes essential for enhancing surgical outcomes and patient care. The potential synergy of artificial intelligence with these innovations holds promise in revolutionizing tumor detection and improving the efficacy of cutaneous malignancy treatments.

Periocular and ocular surface nonmelanoma skin cancer

Periocular and ocular surface nonmelanoma malignancies, including basal cell carcinoma (BCC), squamous cell carcinomas (SCC), and ocular surface squamous neoplasia (OSSN), are rare, but their management requires special considerations. The most common periocular malignancy is BCC, which constitutes 80% to 96% of tumors, followed by SCC, which represents 5% to 10% of tumors. OSSN represents a spectrum of diseases that encompass dysplastic alteration to the squamous epithelium of the eye. OSSN ranges from squamous dysplasia to conjunctival intraepithelial neoplasia/carcinoma in situ to invasive SCC, which is the most common ocular malignancy. These tumors can be staged using the eighth edition of the American Joint Committee on Cancer categorization system. The standard of care for periocular malignancies is Mohs micrographic surgery, while medical management with 5-fluorouracil (5-FU), interferon alfa-2b (INF), and mitomycin C (MMC) or "no touch" surgical excision are options for OSSN. Systemic therapies, including sonic hedgehog inhibitors for BCC and epidermal growth factor inhibitors and immune-checkpoint inhibitors for SCC, can be utilized for advanced disease. Recurrence rates are higher for periorbital and ocular malignancies than their respective cutaneous counterparts. These carcinomas and their respective treatments have unique side effects and considerations in an effort to preserve visual function.

Perianal Malignancies: A Review for the Dermatologic Surgeon

BACKGROUND

Perianal malignancies are rare tumors with unique presentations and treatment options.

OBJECTIVE

To review published literature about primary malignancies that present on perianal skin and published guidelines and treatment options.

MATERIALS AND METHODS

A PubMed search was conducted for original articles about perianal malignancies.

RESULTS

Squamous cell carcinoma, basal cell carcinoma, melanoma, and extramammary Paget disease are the most common tumors to present on perianal skin. Anal squamous cell carcinoma incidence is increasing and certain populations may benefit from screening. Surgical management is often recommended for localized perianal tumors.

CONCLUSION

Dermatologic surgeons should be familiar with the presentation and treatment options available for perianal malignancies.

Mohs Surgeons Dominate Cutaneous Reconstructions in Cosmetically and Functionally Sensitive Sites: Medicare Trends From 2013 to 2019

BACKGROUND

Although dermatologists perform more cutaneous reconstructions than any other specialists for the Medicare population, the perception of dermatologists as surgeons may not be as fully recognized. Mohs surgeons are trained in complex reconstructions of cosmetically and functionally sensitive (CFS) sites, although the proportion they account for is unknown.

OBJECTIVE

To quantify the proportion of cutaneous reconstructions in CFS sites performed by Mohs surgeons compared with other specialists, and to identify trends from 2013 to 2019.

METHODS

A cross-sectional analysis was performed using the Medicare Public Use Files for 2013 to 2019. Data were stratified by physician specialty, with dermatologists further subdivided into Mohs surgeons and non-Mohs dermatologists.

RESULTS

Mohs surgeons performed 75.3% of all reconstructions in 2019, a significant increase from 2013 ( p < .0001). Mohs surgeons dominated nearly every type of CFS cutaneous reconstruction, with significant increases in proportion ( p < .0001) from 2013 to 2019 for every category except interpolation flaps. Complex repairs were the most commonly performed cutaneous reconstruction type.

CONCLUSION

Mohs surgeons perform far more cutaneous reconstructive surgeries in CFS sites than any other specialty for the Medicare population, with significant increases in their lead over the study period.

Nasal reconstructive techniques following Mohs surgery or excisions: a systematic review

Numerous reconstructive techniques for nasal defects following skin cancer removal have been described; however, the literature lacks a comprehensive systematic review. Our objective was to systematically review nasal reconstruction methods after tumor removal, correlate the use of specific techniques to the nasal subunits involved, assess the quality of the available evidence, and set the stage for future research on this topic. Eight databases were searched for studies published in English from January 2004 to December 2018 containing repair data for nasal defects following Mohs or excision for four or more subjects. Recorded data included author specialties, study design, subject number, demographics, defect characteristics, procedure type, reconstructive methods, outcome measures, and complications. One-hundred and eleven studies were included. Study types included case series (73%), observational cohort studies (25%), and clinical trials (2%). Most authors were dermatologic surgeons (61%). Resection was most commonly performed via Mohs (82%). Flaps (42%), linear closures (28%) and grafts (25%) were most utilized for reconstruction. In Zones I and II, transposition flaps were the most common followed by advancement flaps. In Zone III, full thickness skin grafts were the most common repair. Most studies were case series or small cohort studies, representing low level evidence. Flaps are the most common method described in the literature for nasal reconstruction. The overall quality of the evidence available on this topic is low.

Combined Mohs Micrographic Surgery in a Collision Tumor

We present the case of a 73-year-old male patient with a collision tumor in the right ear, consisting of a basal cell carcinoma and melanoma in situ. He was managed with Mohs micrographic surgery combining paraffin-embedded sections and frozen sections. Multiple surgical stages were required to obtain tumor-free margins. The surgical defect was reconstructed by plastic surgery, achieving the preservation of the ear. The technique of combining two processing sections is useful in the treatment of the collision of basal cell carcinoma with malignant melanoma.

The Treatment of Non-Melanoma Skin Cancer with Image-Guided Superficial Radiation Therapy: An Analysis of 2917 Invasive and In Situ Keratinocytic Carcinoma Lesions

Introduction

An image-guided form of superficial ionizing radiation therapy (IGSRT) is becoming a commonly used alternative to surgery for non-melanoma skin cancer (NMSC). However, there is little literature evidence evaluating the efficacy and safety of this approach. This study evaluates the efficacy and safety of IGSRT in treating a large number of patients with NMSC.

Methods

The medical records of 1632 stage 0–II patients with 2917 invasive and in situ NMSC lesions treated from years 2017 to 2020 were reviewed. No patients had clinical evidence of regional lymph node or distant disease at presentation.

Results

Treatment, guided by pre-treatment ultrasound imaging to adjust radiation energy and dose, combined with a fractionation treatment schedule of 20 or more treatment fractions, was safe and well tolerated. Of 2917 NMSC lesions treated, local tumor control was achieved in 2897 lesions, representing a 99.3% rate of control.

Conclusion

IGSRT should be considered as a first-line option for treating NMSC tumors in suitable early stage patients. Cure rates observed in this initial period of follow-up are similar, and potentially superior with further follow-up, to traditional superficial radiation therapy (SRT) and surgical options.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40487-021-00138-4.