Slow Mohs Micrographic Surgery for Acral Melanoma Treatment in Korean Patients

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

Comparative Analysis of Slow Mohs Surgery in Melanoma and Mohs Micrographic Surgery in Squamous Cell Carcinoma and Basal Cell Carcinoma

Skin cancer is one of the most common types of cancer worldwide, and it can affect people of all ages, races, and genders. Mohs micrographic surgery (MMS), a specialized type of skin cancer surgery, boasts the highest cure rates for various types of skin malignancies. Slow Mohs surgery (SMS) is a methodical and meticulous approach to MMS that involves careful and deliberate examination of tissue samples to ensure the complete removal of skin cancer while preserving as much healthy tissue as possible. Both SMS and MMS have been indicated to be effective treatment options for skin cancer, depending on the type and stage of cancer. This case-control study analysis compares the efficacy of SMS for melanoma with that of MMS for squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). We analyzed data from the past two decades to assess recurrence rates and treatment-related complications. Our findings suggest that SMS for melanoma achieves comparable outcomes to MMS in SCC and BCC. Both approaches demonstrated similar cure rates and complication profiles. However, further prospective studies are necessary to solidify these findings and refine the specific role of SMS in melanoma therapy.

Pressure and Skin: A Review of Disease Entities Driven or Influenced by Mechanical Pressure

Skin perceives and reacts to external mechanical forces to create resistance against the external environment. Excessive or inappropriate stimuli of pressure may lead to cellular alterations of the skin and the development of both benign and malignant skin disorders. We conducted a comprehensive literature review to delve into the pressure-induced and aggravated skin disorders and their underlying pressure-related mechanisms. Dysregulated mechanical responses of the skin give rise to local inflammation, ischemia, necrosis, proliferation, hyperkeratosis, impaired regeneration, atrophy, or other injurious reactions, resulting in various disease entities. The use of personal devices, activities, occupations, weight bearing, and even unintentional object contact and postures are potential scenarios that account for the development of pressure-related skin disorders. The spectrum of these skin disorders may involve the epidermis (keratinocytes and melanocytes), hair follicles, eccrine glands, nail apparatuses, dermis (fibroblasts, mast cells, and vasculature), subcutis, and fascia. Clarifying the clinical context of each patient and recognizing how pressure at the cellular and tissue levels leads to skin lesions can enhance our comprehension of pressure-related skin disorders to attain better management.

From Centimeters to Millimeters: The Evolution of the Surgical Margins for Melanoma-A Historical Review

BACKGROUND

With an improved understanding of tumor biology and behavior, the recommended margins for the surgical treatment of melanoma have evolved.

OBJECTIVE

We describe the progression of these surgical margins, detailing the historical basis for the 5-cm margin and transitioning to current practice, in which Mohs micrographic surgery (MMS) with immunohistochemistry (IHC) has become increasingly used.

METHODS/MATERIALS

We searched PubMed and Google Scholar for articles published between January 2019 and April 2023 describing the use of MMS for melanoma in situ (MIS) and invasive melanomas.

RESULTS

We identified 12 articles focusing on the use of MMS for MIS and invasive melanomas: 3 meta-analyses and 9 retrospective studies. Two retrospective analyses documented no differences in overall survival between MMS and wide local excision (WLE) and 2 found improved overall survival for MMS compared with WLE. Three retrospective analyses and 3 meta-analyses demonstrated low recurrence rates after the use of MMS for both MIS and invasive melanomas. Finally, 2 retrospective studies documented the success of MMS with IHC using MART-1.

CONCLUSION

Over the past century, the surgical margins for the treatment of melanoma have undergone a marked transformation. MMS with IHC has become increasingly popular given its ability to reliably produce superior clinical outcomes.

Surgical resection margin for T3-T4 primary acral melanoma: a multicenter retrospective cohort study

Although the National Comprehensive Cancer Network (NCCN) guidelines include clear recommendations for the appropriate resection margins in non-acral cutaneous melanoma, the required margin for acral melanoma is controversial. In this retrospective study, we aimed to investigate whether narrow-margin excision is warranted for thick acral melanoma. Records from 277 melanoma patients with stage T3-T4 disease who underwent radical surgery in three centers in China from September 2010 to October 2018 were reviewed. Clinicopathologic data, including age, gender, excision margin (1-2 cm versus ≥ 2 cm), Clark level, Breslow thickness, ulceration, N stage and adjuvant therapy, were included for survival analysis. The patients were followed up until death or March 31, 2021. Log-rank and Cox regression analyses were used to identify prognostic factors for overall survival (OS), disease-free survival (DFS) and local and in-transit recurrence-free survival (LITRFS). Among all enrolled patients, 207 (74.7%) had acral melanoma, and 70 (25.3%) had non-acral cutaneous melanoma. No significant difference in baseline characteristics was identified between non-acral and acral melanoma, except for age (p = 0.004), gender (p = 0.009) and ulceration (p = 0.048). In non-acral melanoma, a resection margin of 1-2 cm was a poor independent prognostic factor for OS [p = 0.015; hazard ratio (HR) (95% CI), 0.26 (0.009-0.77)] and LITRFS [p = 0.013; HR (95% CI), 0.19 (0.05-0.71)] but not for DFS [p = 0.143; HR (95% CI), 0.51 (0.21-1.25)]. Forty-three (20.8%) patients in the acral melanoma group had a 1-2-cm resection margin. The resection margin was not correlated with patients' OS (p = 0.196 by log-rank analysis, p = 0.865 by multivariate survival analysis), DFS (p = 0.080 by log-rank analysis, p = 0.758 by multivariate survival analysis) or LITRFS (p = 0.354 by log-rank analysis) in acral melanoma. As recommended in the NCCN guidelines, a resection margin ≥ 2 cm is required for non-acral cutaneous melanoma. Meanwhile, a narrow resection margin (1-2 cm) may be safe for patients with acral melanoma.

The clinical effect of modified slow Mohs circular skin biopsy on penoscrotal extramammary Paget's disease

OBJECTIVE

Determining the tumor margin is the main problem in penoscrotal extramammary Paget's disease (PEMPD) surgery. This study aimed to explore the role of modified slow Mohs circular skin biopsy in determining the tumor margin in patients with PEMPD before operation.

METHODS

Thirty-six PEMPD patients were divided into the control group and the observation group according to the simple randomization method. The control group, which consisted of 16 patients, underwent wide local excision, and the observation group, which consisted of 20 patients, underwent a modified slow Mohs circular skin biopsy to determine the tumor margin before surgery. The duration of surgery, number of frozen sections, satisfaction with the appearance of the skin, tumor recurrence rate, and incidence of functional sequelae were statistically analyzed.

RESULTS

The number of frozen sections, duration of surgery, incidence of functional sequelae, and tumor recurrence rate in the observation group were lower than in the control group. The satisfaction with the appearance of the skin was higher in the observation group than in the control group, and the difference was statistically significant (P < 0.05).

CONCLUSION

Modified slow Mohs circular skin biopsy can determine the tumor margin before surgery and reduce the number of frozen sections, tumor recurrence rate, and the incidence of functional sequelae. It also increases the postoperative satisfaction of patients.

Slow Mohs micrographic surgery for nail apparatus melanoma in situ

BACKGROUND

Nail apparatus melanoma is a malignant tumor with a high incidence in Chinese melanoma patients. Slow Mohs micrographic surgery is an emerging technique for treating nail apparatus melanoma in situ (NAMIS).

OBJECTIVE

This study evaluated the efficacy and safety of slow Mohs micrographic surgery for treating NAMIS.

METHODS

Patients were enrolled in this retrospective study and treated in a single center from October 1, 2016, to June 30, 2022. Each patient underwent standard slow Mohs micrographic surgery, and follow-up was regularly conducted at clinics.

RESULTS

Ten patients were enrolled in the study. Two patients underwent one Mohs stage, seven underwent two Mohs stages, and one underwent seven Mohs stages. The resection margin ranged from 5 to 25 mm. No severe complications were reported in the treatment, and recurrence of NAMIS was not observed during the follow-up period.

CONCLUSION

Slow Mohs micrographic surgery is a valuable surgical method to treat NAMIS that preserves digit function and can be well tolerated by patients.

No Recurrence in Primary Invasive Stage 1a and 1b Melanoma and Melanoma in Situ Treated With Serial Disk Staged Excision

BACKGROUND

Optimal surgical treatment modality for invasive melanoma (IM) and melanoma in situ (MIS) has been debated with proponents for standard wide local excision (WLE), serial disk staged excision, and Mohs micrographic surgery.

OBJECTIVE

The purpose of this study is to identify the recurrence rates and surgical margins of invasive stage 1 melanoma and MIS lesions using serial disk staged excision technique with rush permanent processing and "bread loafing" microscopic analysis.

MATERIALS AND METHODS

Recurrence rates and surgical margins of 63 IM and 207 MIS at the University of California Dermatology Surgery Unit were retrospectively reviewed.

RESULTS

No recurrences were observed with average follow-up of 34 and 36 months for IM and MIS, respectively (range, 10-92 months). Average surgical margins were 19.8 mm (SD 9.7) for IM and 12.1 mm (SD 12.2) for MIS.

CONCLUSION

This SSE technique for the treatment of IM and MIS is comparable in efficacy to other SSE techniques, and it offers physicians a simple and accessible alternative to WLE and MMS.