Low recurrence rates for in situ and invasive melanomas using Mohs micrographic surgery with melanoma antigen recognized by T cells 1 (MART-1) immunostaining: tissue processing methodology to optimize pathologic staging and margin assessment

Mohs for Melanoma: A Review of MART-1 Frozen Section Interpretation

BACKGROUND

Mohs surgery for melanoma has been performed for many decades, but advances in the use of immunohistochemistry with frozen sections during Mohs surgery have allowed for more accurate, reliable, and efficient margin assessment with improved local control of the disease.

OBJECTIVE

To describe the use of MART-1 in treating melanoma with Mohs surgery and serve as a primer for the Mohs surgeon adding melanoma cases to their repertoire.

MATERIALS AND METHODS

Review of the literature and discussion of experience with Mohs for melanoma.

RESULTS

Practical approach and pitfalls when assessing margins using MART-1 immunohistochemistry during Mohs surgery for the treatment of melanoma.

CONCLUSION

Mohs for melanoma is an expanding field-education of Mohs surgeons and increasing the practice of this technique has the potential to improve patient outcomes.

Intraoperative Immunohistochemistry During Mohs Micrographic Surgery and Staged Excision Decreases Local Recurrence Rates for Invasive Cutaneous Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Mohs micrographic surgery (MMS) is increasingly used to treat cutaneous melanoma. However, it is unclear whether intraoperative immunohistochemistry (IHC) improves surgical outcomes.

OBJECTIVE

To determine whether intraoperative IHC during MMS and staged excision is associated with a decreased risk of poor surgical outcomes.

MATERIALS AND METHODS

Search of 6 databases identified comparative and noncomparative studies that reported local recurrence after MMS or staged excision with or without IHC for melanoma. Random-effects meta-analysis was used to estimate pooled local recurrence rates, nodal recurrence, distant recurrence, and disease-specific mortality.

RESULTS

Overall, 57 studies representing 12,043 patients with cutaneous melanoma and 12,590 tumors met inclusion criteria. Combined MMS and staged excision with IHC was associated with decreased local recurrence in patients with invasive melanoma (0.3%, 95% CI: 0-0.6) versus hematoxylin and eosin alone (1.8%, 95% CI: 0.8%-2.8%) [ p < .001]. Secondary outcomes including nodal recurrence, distant recurrence, and disease-specific mortality were not significantly different between these 2 groups. Study heterogeneity was moderately-high.

CONCLUSION

Local recurrence of invasive melanoma is significantly lower after MMS and staged excision with IHC as opposed to without IHC. These findings suggest that the use of intraoperative IHC during MMS or staged excision should strongly be considered, particularly for invasive melanoma.Trial Registration PROSPERO Identifier: CRD42023435630.

Oncologic control and predictors of urologic reconstruction after Mohs micrographic surgery for low-risk penile malignancy

PURPOSE

Mohs micrographic surgery (MMS) is a low-risk penile cancer management option. However, contemporary patients' short-term oncologic control and preoperative characteristics predicting reconstruction needs are undefined. This study assesses MMS's oncologic efficacy for low-risk penile cancer and identifies baseline predictors of post-resection reconstruction referral.

METHODS

We retrospectively reviewed 73 adult males with 78 penile cutaneous malignancies treated with MMS from 2005 to 2019. Patients underwent MMS with or without surgical reconstruction. Demographic information, MMS operative details, lesion pathology, and short-term outcomes were recorded. Descriptive statistics for all variables were calculated, and logistic regression identified predictive factors for urologic referral for complex reconstruction.

RESULTS

Seventy-three men with 78 lesions, all staged ≤ cT1a prior to MMS, were identified. Twenty-one men were found to have invasive SCC. Median follow-up was 2.0 years (IQR 0.8-5.2 years). MMS was able to clear the disease in 90.4% of cases. One patient had disease related death following progression. Dermatology closed primarily in 68% of patients. Twenty percent of patients had a complication, most commonly poor wound healing. On univariate and multivariate linear regression analysis, lesion size > 3 cm and involvement of the glans independently predicted the need for referral to a reconstructive surgeon.

CONCLUSIONS

MMS for penile cancer appears to provide sound oncologic control in the properly selected patient. Involvement of a reconstructive surgeon may be needed for glandular and large lesions, necessitating early referral to a comprehensive multidisciplinary care team.

Mohs micrographic surgery in the surgical treatment paradigm of melanoma in situ and invasive melanoma: A clinical review of treatment efficacy and ongoing controversies

Mohs Micrographic Surgery (MMS) for treatment of melanoma offers several advantages over wide local excision (WLE), including complete histologic margin evaluation, same-day resection and closure, and sparing of healthy tissue in critical anatomic sites. Recently, a large volume of clinical data demonstrating efficacy in MMS treatment of melanoma was published, leading to emerging patient safety considerations of incurred treatment costs, risk of tumor upstaging, and failure of care coordination for sentinel lymph node biopsy (SLNB). MMS offers a safe, effective, and value-based treatment for both melanoma in situ (MIS) and invasive melanoma (IM), particularly with immunohistochemistry use on frozen sections. Compared to wide local excision, MMS treatment demonstrates similar or improved outcomes for local tumor recurrence, melanoma-specific survival, and overall survival at long-term follow-up. Tumor upstaging risk is low, and if present, alteration to clinical management is minimal. Discussion of SLNB for eligible head and neck IM cases should be done prior to MMS. Though challenging, successful multidisciplinary coordination of SLNB with MMS has been demonstrated. Herein, we provide a detailed clinical review of evidence for MMS treatment of cutaneous melanoma and offer recommendations to address current controversies surrounding the evolving paradigm of surgical management for both MIS and invasive melanoma (IM).

Pathologic Upstaging of Cutaneous Melanoma After Mohs Micrographic Surgery

BACKGROUND

Mohs micrographic surgery (MMS) is used for melanoma in situ (MIS) and thin invasive melanomas, particularly on the head and neck, during which a debulk section is typically prepared. Tumor upstaging occurs if the debulking specimen meets criteria for an increased tumor (T) stage per the American Joint Committee on Cancer 8th edition compared with the initial biopsy. Upstaging can alter survival and recurrence outcomes, resulting in increased patient morbidity and mortality.

OBJECTIVE

To determine the rate of cutaneous melanoma upstaging during MMS.

MATERIALS AND METHODS

A multicenter study was performed. Information from electronic medical records from 3 dermatologic surgeons performing MMS for cutaneous melanoma were logged from January 1, 2017 to December 31, 2021. Deidentified information regarding patient demographics and tumor characteristics was recorded.

RESULTS

Three-hundred and ten cases of cutaneous melanoma treated with MMS were identified. 2.3% of cases were upstaged, ranging from T1a to T3a. No significant risk factors for upstaging were identified.

CONCLUSION

Our data demonstrate a lower rate of cutaneous melanoma upstaging during MMS than the current literature. Differences may be accounted for because of differing patient populations, cutaneous melanoma detection at an earlier clinical stage, and evolving melanoma histologic criteria.

Reconstruction after Mohs Surgery for Digit Melanoma: Description of Techniques and Postoperative Limb Function

Introduction

Mohs surgery and reconstruction has enabled tissue-preserving resection of cutaneous malignancies. The goal of our case series evaluation is to present reconstructive techniques and functional outcomes in patients undergoing digit-sparing treatment for primary melanoma.

Materials and Methods

A chart review was performed to identify consecutive patients undergoing Mohs surgery and reconstruction for melanoma of the digits. Quality of life (QOL) survey was performed to assess function after the procedure.

Results

Thirty-two patients (13 hand, 19 foot, Age: 65.03 +/-17.78 years) who were undergoing Mohs surgery were identified. No recurrence was identified with an average follow-up of 16.1 months (1-95 months). The average defect size was 5.79 +/-4.54 cm2. Reconstruction was performed 0-4 days after resection. The most common techniques included full-thickness skin graft (FTSG) (N = 7), collagen matrix + FTSG (N = 4), and volar advancement flap (N = 7). The reconstructive technique choice appears correlated with defect size (p = 0.0125). Neuro-QOL upper extremity survey results showed a difference that approached statistical significance between patients who underwent digit-sparing treatment (n = 7) versus direct to amputation controls (n = 5) (p = 0.072). No survey differences between digit-sparing treatment (n = 10) and amputation (n = 8) were identified in the lower extremity (p = 0.61).

Conclusion

Our results show digit-sparing treatment can confirm clear surgical margins and a trend toward improvement in upper extremity function compared with immediate amputation.

Top 100 Most Cited Articles in Mohs Micrographic Surgery: A Bibliometric Analysis

BACKGROUND

Bibliometric analysis is a scientific method that can derive insights into major publications' trends within a field. Currently, no bibliometric study has been conducted for Mohs micrographic surgery (MMS).

OBJECTIVE

To characterize the most frequently cited articles in MMS.

METHODS

Web of Science was used to identify the 100 most cited publications on MMS between 1970 and 2022. Articles were analyzed by title, authorship, institution, journal, year, citation frequency, originating country, funding, citation index, Altmetric score, impact factor, Eigenfactor score, and article influence score.

RESULTS

Since January 2023, the top 100 articles had 9,096 total citations, ranging from 47 to 304. The top cited publication was "Mohs surgery is the treatment of choice for recurrent (previously treated) basal-cell carcinoma" in 1989. The top contributing organization was Harvard University (17%) and top contributing authors were Brodland, DJ (12%) and Zitelli, JA (11%). The year 2005 accounted for most of the articles (12%). Most articles were from the Journal of the American Academy of Dermatology (32%) and Dermatologic Surgery (27%). The United States contributed to 76% of the top articles.

CONCLUSION

This bibliometric analysis offers researchers a detailed overview of important MMS publications and provides useful data into current findings steering MMS research and practice.

An Update and Review of Clinical Outcomes Using Immunohistochemical Stains in Mohs Micrographic Surgery for Melanoma

BACKGROUND

Mohs micrographic surgery (MMS) provides optimal margin control through complete peripheral and deep margin assessment. The treatment of melanoma using MMS has historically been limited by difficulty in interpreting melanocytes using frozen sections. Immunohistochemical (IHC) staining, a technique whereby chromogen-tagged antibodies are used to detect antigens of interest, has revolutionized the surgical treatment of melanoma.

OBJECTIVES

This article provides an update and literature review of current IHC stains used in MMS for melanoma, their sensitivities and specificities, and clinical outcomes.

MATERIALS AND METHODS

A PubMed search was performed using keywords including "immunohistochemistry," "staining," and "Mohs surgery." Articles related to the use of IHC staining for the treatment of melanoma with MMS were included.

RESULTS

Six IHC stains met the criteria for the review including melanoma antigen recognized by T cells (MART-1), SRY-related HMG-box (SOX10), microphthalmia-associated transcription factor, HMB-45, MEL-5, S-100, and preferentially expressed antigen in melanoma.

CONCLUSION

The adaptation of IHC methods to frozen sections has enabled MMS to become a preferred treatment option for melanoma in special-site areas. Future studies are needed to standardize IHC techniques and to define best practices when using frozen section in the treatment of melanoma.

Outcomes of invasive melanoma of the head and neck treated with Mohs micrographic surgery - A multicenter study

BACKGROUND

There are no randomized controlled trials to guide surgical margins for invasive head and neck (H&N) melanoma using conventional excision. Mohs micrographic surgery (MMS) has shown improved local recurrence rates and survival for invasive H&N melanomas.

OBJECTIVE

Determine local recurrence (LR), nodal recurrence, and distant recurrence rates, and disease specific survival for invasive melanoma of the H&N treated with MMS.

METHODS

A retrospective multicenter study of 785 cases of invasive H&N melanoma treated with MMS using frozen sections with melanoma antigen recognized by T-cells 1 immunohistochemical staining was performed to evaluate long-term outcomes over 12-years.

RESULTS

785 melanomas (thickness: 0.3 mm-8.5 mm) were treated with MMS. LR, nodal recurrence, and distant recurrence rates were 0.51% (4/785), 1.0% (8/785), and 1.1% (9/785) respectively. For T1, T2, T3, and T4 tumors LR was 0.16% (1/636), 1.18% (1/85), 2.22% (1/45), and 5.26% (1/19), respectively. Five and 10-year disease specific survival were 96.8% (95% CI 95.0% to 98.5%) and 93.4% (95% CI 88.5% to 98.3%).

LIMITATIONS

A nonrandomized retrospective study.

CONCLUSION

MMS achieves significant improvements in LR compared to a meta-analysis of historical cohorts of patients treated with conventional excision. MMS should be considered an important surgical option for invasive H&N melanoma.

Local Recurrence Rates After Excision of Desmoplastic Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Few prospective studies have evaluated local recurrence rates (LRR) after excision of desmoplastic melanoma (DM); however, several retrospective studies have reported high LRR.

OBJECTIVE

To determine LRR after excision of DM and evaluate factors affecting LRR.

MATERIALS AND METHODS

Systematic review of the PubMed, Embase, and Web of Science databases was performed to identify studies reporting local recurrence after excision of DM with conventional wide local excision (WLE), Mohs micrographic surgery (MMS), or staged excision (SE). Meta-analysis was performed to calculate summary LRR and pooled risk ratios (RR).

RESULTS

Literature search identified 4 studies evaluating MMS or SE (total n = 61 DM). 53 studies assessed WLE ( n = 3,080) and were analyzed quantitatively. The overall LRR after WLE of DM was 21% (95% CI, 0.16-0.28; n = 2,308). Local recurrence rate was higher with positive/unknown histologic excision margins (49%, 95% CI, 0.25-0.74; n = 91) versus negative histologic margins (11%, 95% CI, 0.07-0.17; n = 1,075; [ p < .01]). Neurotropism was also associated with increased LRR (RR, 1.79; 95% CI, 1.34-2.38, p < .01; n = 644).

CONCLUSION

DM has high LRR after WLE. Local recurrence risk was greatest with positive excision margins, indicating the importance of achieving negative microscopic margins. Greater study of MMS and SE for DM is required.

Differences in sentinel lymph node biopsy utilization in eligible melanoma patients treated with Mohs micrographic surgery or wide local excision: A population-based logistic regression model and survival analysis

BACKGROUND

Primary melanoma management relies on tumor extirpation and staging sentinel lymph node biopsy (SLNB) in eligible patients. This study compares SLNB utilization in patients undergoing wide local excision (WLE) or Mohs micrographic surgery (MMS).

METHODS

American Joint Committee on Cancer seventh edition ≥ patients with T1b melanoma undergoing WLE or MMS in the Surveillance, Epidemiology, and End Results program were included. Propensity score matching was performed to compare patients who underwent MMS or WLE. Kaplan-Meier analysis and Fine-Gray cumulative incidence functions were used for overall and melanoma-specific survival.

RESULTS

Eight hundred twenty-five MMS cases and 38,760 WLE cases were identified. SLNB was performed in 32.61% of MMS patients and 61.77% of WLE patients with positive rates of 12.5% and 14.82%, respectively. Multiple logistic regression of factors associated with SLNB utilization revealed that WLE, male gender, younger age, extremity location, and nodular and rare melanoma subtypes were significantly associated with increased odds of receiving SLNB whereas head and neck location and lentigo maligna melanoma subtype were significantly less likely to receive SLNB.

LIMITATIONS

Potential selection bias from a retrospective data set.

CONCLUSION

Patients receiving WLE for ≥ T1b melanoma are more likely to receive a SLNB than patients undergoing MMS.

Assessing Rates of Positive Surgical Margins After Standard Excision of Vulvar Melanomas

BACKGROUND

Vulvar melanoma is a rare malignancy with frequent recurrence and poor prognosis. National guidelines recommend wide local excision of these tumors with allowances for narrower margins for anatomic and functional limitations, which are common on specialty sites. There is presently a lack of data of margin positivity after standard excision of vulvar melanomas.

OBJECTIVE

We aim to evaluate the rate of positive margins after standard excision of vulvar melanomas.

MATERIALS AND METHODS

Retrospective cohort study of surgically excised vulvar melanomas from the NCDB diagnosed from 2004 to 2019.

RESULTS

We identified a total of 2,226 cases. Across surgical approaches and tumor stages, 17.2% (Standard Error [SE]: 0.8%) of cases had positive surgical margins. Among tumor stages, T4 tumors were most commonly excised with positive margins (22.9%, SE: 1.5%). On multivariable survival analysis, excision with positive margins was associated with significantly poorer survival (Hazard Ratio 1.299, p = .015).

CONCLUSION

We find that positive margin rates after standard excision of vulvar malignancies are higher than for other specialty site melanomas. Our data suggest that use of surgical approaches with complete margin assessment may improve local control and functional outcomes for patients with vulvar melanoma as they have for patients with other specialty site melanomas.

Challenges in the Complex Management of Neglected Cutaneous Melanomas in the Head and Neck Area: A Single Center Experience

Familiar controversies in the management of head and neck melanomas are more remarkable in locally advanced cases, and they represent a treatment challenge both surgically and oncologically. In our retrospective study, patients with surgically treated primary malignant melanoma of the head and neck region larger than 3 cm in diameter were included. Five patients met our inclusion criteria. In all cases, wide excision and immediate reconstruction were performed without sentinel lymph node biopsy. The defect on the scalp was covered by a split skin graft, with local flaps chosen for reconstruction on the face on an individual basis. After a 2-6 year follow-up, a good oncological, functional, and esthetic result was achieved. Our results show that in the case of large, locally advanced melanomas, surgical treatment still plays a crucial role that can provide long-term local control and support the effect of systemic treatment.

Local Recurrence Rates of Malignant Melanoma After Mohs Micrographic Surgery Are Lowest With 5- to 10-mm Initial Margins: A Systematic Review and Meta-Analysis

BACKGROUND

Current consensus guidelines have discouraged the use of sub-0.5-cm (in situ) and sub-1-cm (invasive) margins when performing Mohs micrographic surgery (Mohs) for melanoma, with minimal evidence to guide this recommendation.

OBJECTIVE

To compare melanoma local recurrence rates after Mohs based on initial margin size.

MATERIALS AND METHODS

A systematic review and meta-analysis was conducted with search terms including Mohs micrographic surgery, surgical margin, recurrent disease, and melanoma.

RESULTS

Forty-three studies were included. The 5- to 10-mm margin category had a statistically significant lower local recurrence compared with 1- to 5-mm and 5-mm categories. Recurrence for 1- to 5-mm, 5-mm, 5- to 10-mm, and 10-mm categories were 2.3% (CI 0.8-3.5, p < .001), 1.4% (CI 0.6-2.2, p < .001), 0.3% (CI 0.2-0.5, p < .001), and 6.1% (CI -6.7 - 18.8, p = .349), respectively. Number of stages for 1 to 5, 5, 5 to 10, and 10-mm categories were 1.8, 1.8, 1.6, and 1.6, respectively. There was no statistically significant difference between the groups (p = .694).

CONCLUSION

Five- to 10-mm margins were associated with the lowest local recurrence rates. A 5- to 10-mm initial margin should be considered where other factors (tumor characteristics, anatomical or functional considerations) allow.

Staged Excision of Lentigo Maligna of the Head and Neck: Assessing Surgical Excision Margins With Melan A, SOX10, and PRAME Immunohistochemistry

BACKGROUND

Staged excision has emerged as a superior treatment option for lentigo maligna (LM) of the head and neck when compared with conventional wide local excision. Assessing surgical excision margins for remaining LM poses a diagnostic challenge.

OBJECTIVES

To determine whether immunohistochemical (IHC) staining with SOX10 and preferentially expressed antigen in melanoma (PRAME) aids in diagnosing LM on excision margins compared with conventional hematoxylin and eosin and Melan A IHC staining.

METHODS

This study included cases of LM of the head and neck treated with staged excision. Histological findings were reviewed according to standard criteria for the diagnosis of LM and compared with the results after IHC staining for Melan A, SOX10, and PRAME.

RESULTS

The cohort consisted of 35 sections. Based on hematoxylin and eosin and Melan A IHC staining, 23 sections were diagnosed as LM by the initial pathologist. Further staining with SOX10 IHC showed only 8 to be consistent with a diagnosis of LM and 9 revealing features of actinic melanocyte hyperplasia. PRAME was positive in 5 of the 8 cases of LM and negative in all 9 cases of actinic melanocyte hyperplasia (P = 0.009). The presence of melanocyte nests (P = 0.29) and pagetoid spread (P = 0.003) was the most reliable histological findings distinguishing LM from its mimics.

CONCLUSION

SOX10 is a more specific and sensitive marker for melanocytes when assessing for LM on excision margins compared with Melan A. The addition of PRAME can be useful to confirm or exclude the diagnosis in challenging cases.

Permanent section margin concordance after Mohs micrographic surgery with immunohistochemistry for invasive melanoma and melanoma in situ: A retrospective dual-center analysis

BACKGROUND

Mohs micrographic surgery (MMS) for melanoma practices vary among dermatologic surgeons. The implementation of immunohistochemical staining in MMS for melanoma mitigates challenges associated with slide interpretation; however, the reliability of melanoma antigen recognized by T cells 1 (MART-1), the preferred immunostain for melanoma, has yet to be compared with permanent section pathology.

OBJECTIVE

To assess concordance rates of MART-1 frozen sections and permanent section pathologic interpretation of melanoma treated with MMS.

METHODS

A dual-center retrospective analysis was conducted to collect concordance and demographic data. Chi-square tests were performed for group comparisons of categorical variables.

RESULTS

Of the 379 permanent sections sent, 367 were concordant with frozen section pathology for an overall concordance rate of 96.8%. Cases were stratified into indeterminately concordant and indisputably concordant. Twenty-two (6%) of cases were indeterminately concordant, whereas 345 (94.0%) of cases were indisputably concordant.

LIMITATIONS

The concordance rate is derived from a comparison of adjacent tissue margins, an inevitable consequence of utilizing 2 techniques.

CONCLUSION

To the author's knowledge, this study represents the largest investigation examining concordance rates of MART-1 frozen sections in Mohs for melanoma. High concordance disputes the ongoing need for additional permanent margins when using MART-1 in routine cases.

Lentigo Maligna of the head and neck: A retrospective study assessing surgical excision margins in a South African population

Background

Lentigo maligna (LM) is a subtype of melanoma in situ that occurs on sun-damaged skin and is associated with significant subclinical extension beyond the clinical margins of the lesion.

Objectives

This study aimed to determine if the standard recommended tumor excision margins for LM are adequate to achieve a 97% clearance rate and if any patient or tumor characteristics warranted wider margins.

Methods

This study is a retrospective chart review of all patients who were diagnosed with LM of the head and neck and treated with staged excision.

Results

The study included 64 patients. With a 6 mm surgical excision margin, only 60.9% of LM were completely excised. A 9 mm margin resulted in complete clearance of 71.9% of LM cases, and a 12 mm margin resulted in complete clearance in 90.6%. A surgical excision margin of 18 mm would have been required to excise 96.7% of tumors completely. Recurrent tumors (P = .01) and tumor size larger than 20 mm were associated with wider surgical excision margins (P = .154).

Conclusion

This study of LM in a South African population corroborates that the standard surgical excision margins recommended by international melanoma guidelines for LM are inadequate to achieve a 97% clearance rate.

Recurrence Rate for Melanoma Excised by Mohs Micrographic Surgery Without Immunostaining

BACKGROUND

Mohs micrographic surgery (MMS) is becoming increasingly popular for the treatment of cutaneous melanoma (CM) as multiple studies have demonstrated favorable outcomes for local recurrence and overall survival.

OBJECTIVE

To analyze the outcomes of noninvasive (NIM) and invasive melanomas (IM) using MMS with fresh frozen sections. The primary outcome was local recurrence. The secondary outcome was to identify mean surgical margins based on tumor type and location.

METHODS

Retrospective cohort study of 224 cases of CM treated from 2006 to 2016 at a tertiary academic center with MMS and fresh frozen sections by a single Mohs surgeon.

RESULTS

The overall recurrence rate was 2.6% with a mean follow-up of 36.2 months. The recurrence rate for NIM versus IM was 1.6% and 7%, respectively. The mean margins for NIM and IM were 7.9 mm and 10.1 mm, respectively. These varied by tumor site and location.

CONCLUSION

This study supports the use of MMS in the treatment of CM and highlights how narrower surgical margins for NIM of the head and neck can be achieved without increasing risk of local recurrence.

Mohs Micrographic Surgery for the Treatment of Cutaneous Melanomas of the Head and Neck

Surgical excision achieving clear histologic margins remains the mainstay treatment for primary cutaneous melanoma. Tumors of the head and neck, particularly those arising in chronically sun-damaged skin, often demonstrate extensive and asymmetric subclinical extension. Over the decades, this has proven to be a significant problem for tumors arising on the head and neck, as anatomic and functional complexities of these areas have led to suboptimal surgical treatment, yielding unacceptably high rates of local recurrence and persistently positive margins with traditional wide local excision. Patients who undergo Mohs micrographic surgery may have improved survival over those who undergo wide local excision.

Local Recurrence of Melanoma Is Higher After Wide Local Excision Versus Mohs Micrographic Surgery or Staged Excision: A Systematic Review and Meta-analysis

BACKGROUND

Complete removal of melanoma is a primary goal of excision, and local recurrence is one measure to evaluate the efficacy of surgical technique.

OBJECTIVE

To compare published local recurrence rates for melanoma treated with Mohs micrographic surgery (MMS) or staged excision versus wide local excision (WLE).

METHODS AND MATERIALS

Search of 6 databases identified comparative and noncomparative studies that reported local recurrence rates after MMS, staged excision, or WLE for melanoma. Random-effects meta-analysis was used to estimate odds ratios and 95% confidence interval (CI) from comparative studies and event rates from noncomparative studies.

RESULTS

Of the 71 studies included (16,575 patients), 12 were comparative studies (2,683 patients) and 56 were noncomparative studies (13,698 patients). Comparative studies showed increased recurrence after WLE compared with MMS or staged excision (odds ratio [OR], 2.5; 95% CI, 1.4-4.6) and compared with MMS alone (OR, 3.3; 95% CI, 1.8-5.9). Pooled data from comparative and noncomparative studies showed a local recurrence rate of 7% after WLE (95% CI, 5%-11%), 3% after staged excision (95% CI, 2%-4%), and less than 1% after MMS (95% CI, 0%-1%). Statistical heterogeneity was moderate to high.

CONCLUSION

Local recurrence of melanoma is significantly lower after MMS (<1%) and staged excision (3%) compared with WLE (7%).

A review of Mohs Micrographic Surgery for skin cancer: Part 1 - melanoma and rare skin cancers

Mohs micrographic surgery is a precise and effective method commonly used to treat high risk basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) on the head and neck. Whilst the majority of evidence for Mohs relates to keratinocyte cancers, there is published evidence for other types of skin cancer. This review aims to discuss the evidence for using MMS to treat six different types of skin cancer, including melanoma, lentigo maligna, dermatofibrosarcoma protuberans, atypical fibroxanthoma, microcystic adnexal carcinoma and pleomorphic dermal sarcoma, particularly in the context of survival rates and cancer recurrence. These cancers were chosen as there was sufficient literature for inclusion and given MMS is most useful when cancers are contiguous, rather than for cancers with marked metastatic potential such as angiosarcoma or merkel cell carcinoma. We searched Medline, Pubmed and Embase using the keywords: 'melanoma', 'mohs micrographic surgery', 'lentigo maligna', 'dermatofibrosarcoma protuberans', 'atypical fibroxanthoma', 'microcystic adnexal carcinoma' and 'pleomorphic dermal sarcoma' along with their appropriate synonyms, to identify the relevant English-language articles from the year 2000 onwards given that literature for Mohs on non-keratinocyte is sparse prior to this date. A MeaSurement Tool to Assess systematic Reviews (AMSTAR) was used to assess the validity of systematic reviews. Further high-quality, multi-centre randomised trials are necessary to establish the indications and efficacy of MMS for rarer cancers, particularly for AFX and PDS, where limited studies were identified.

Differences Between Recommended Surgical Margins and Measured Histological Margins in Malignant Melanoma In Situ and Malignant Melanomas

ABSTRACT

Wide local excision (WLE) using appropriate surgical margins is the standard surgical management for malignant melanoma in situ (MMIS) and primary cutaneous malignant melanoma (MM). The actual width of the histologic margins is frequently not assessed, whereas narrow histologic margins are associated with an increase in local melanoma recurrence. Our objective was to analyze the actual measured histological margins of WLE specimens of MMIS and MM cases and compare them with their recommended surgical margins. A retrospective study of formalin fixed specimens of MMIS and invasive MM treated with WLE from a large university-affiliated dermatopathology laboratory was conducted. Among a total of 164 MMIS and 128 MM cases, 14 MMIS (8.5%) and 7 MM (5.9%) had positive lateral margins. The median histologic margin for MMIS, after a 15% tissue shrinkage adjusted, was 2.7 mm [1.3-3.9] for LM type and 3.9 mm [2.3-5.6] for non-LM type, in contrast to the recommended 5-mm margin. In 96 MM of T1 type (≤1.0 mm), the median adjusted histologic margin was 6.7 mm [3.5-9.1] in contrast to the recommended 10-mm margin. These results show that measured and adjusted median histologic margins in WLE specimens in both MMIS and MM of T1 type were significantly narrower than the recommended surgical margins, regardless of anatomic location. These differences are concerning, whether they reflect clinicians' intentional or unintentional deviation from recommended guidelines.

Systematic Review of Technical Variations for Mohs Micrographic Surgery for Melanoma

BACKGROUND

Mohs micrographic surgery (MMS) for cutaneous melanoma is becoming more prevalent, but surgical technique varies.

OBJECTIVE

To define variations in published techniques for MMS for melanoma.

METHODS AND MATERIALS

A systematic review was performed of PubMed, EMBASE, and Scopus databases to identify all articles describing surgical techniques for MMS for melanoma. Technical details were recorded for the preoperative, intraoperative, and postoperative phases of MMS.

RESULTS

Twenty-four articles were included. Mohs surgeons vary in how they assess clinical margins, how wide a margin they excise on the first MMS layer, and how they process tissue to determine tumor stage and margin clearance during MMS for melanoma.

CONCLUSION

Mohs micrographic surgery for melanoma is performed with varied surgical techniques. To establish best practices, additional research is necessary to determine how different techniques affect outcomes.

Association of Treatment Facility Characteristics With Overall Survival After Mohs Micrographic Surgery for T1a-T2a Invasive Melanoma

Importance

Early-stage melanoma, among the most common cancers in the US, is typically treated with wide local excision. However, recent advances in immunohistochemistry have led to an increasing number of these cases being excised via Mohs micrographic surgery (MMS). Although studies of resections for other cancers have reported that facility-level factors are associated with patient outcomes, it is not yet established how these factors may affect outcomes for patients treated with Mohs micrographic surgery.

Objective

To evaluate the association of treatment center academic affiliation and case volume with long-term patient survival after MMS for T1a-T2a invasive melanoma.

Design, Setting, and Participants

In a retrospective cohort study, 4062 adults with nonmetastatic, T1a-T2a melanoma diagnosed from 2004 to 2014 and treated with MMS in the National Cancer Database (NCDB) were identified. The NCDB includes all reportable cases from Commission on Cancer-accredited facilities and is estimated to capture approximately 50% of all incident melanomas in the US. Multivariable survival analyses were conducted using Cox proportional hazards models. Data analysis was conducted from February 27 to August 18, 2020.

Exposures

Treatment facility characteristics.

Main Outcomes and Measures

Overall survival.

Results

The study population included 4062 patients (2213 [54.5%] men; median [SD] age, 60 [16.3] years) treated at 462 centers. Sixty-two centers were top decile-volume facilities (TDVFs), which treated 1757 patients (61.9%). Most TDVFs were academic institutions (37 of 62 [59.7%]). On multivariable analysis, treatment at an academic center was associated with a nearly 30% reduction in hazard of death (hazard ratio, 0.730; 95% CI, 0.596-0.895). In a separate analysis, treatment at TDVFs was also associated with improved survival (hazard ratio, 0.795; 95% CI, 0.648-0.977).

Conclusions and Relevance

In this cohort study, treatment of patients with T1a-T2a invasive melanoma excised with MMS at academic and top decile-volume (≥8 cases per year) facilities was associated with improved long-term survival compared with those excised by MMS at nonacademic and low-volume facilities. Identification and protocolization of the practices of these facilities may help to reduce survival differences between centers.

Systematic review and meta-analysis of local recurrence rates of head and neck cutaneous melanomas after wide local excision, Mohs micrographic surgery, or staged excision

BACKGROUND

Prospective trials have not compared the local recurrence rates of different excision techniques for cutaneous melanomas on the head and neck.

OBJECTIVE

To determine local recurrence rates of cutaneous head and neck melanoma after wide local excision (WLE), Mohs micrographic surgery (MMS), or staged excision.

METHODS

A systematic review of PubMed, EMBASE, and Web of Science identified all English case series, cohort studies, and randomized controlled trials that reported local recurrence rates after surgery for cutaneous head and neck melanoma. A meta-analysis utilizing a random effects model calculated weighted local recurrence rates and confidence intervals (CI) for each surgical technique and for subgroups of MMS and staged excision.

RESULTS

Among 100 manuscripts with 13,998 head and neck cutaneous melanomas, 51.0% (7138) of melanomas were treated by WLE, 34.5% (4826) by MMS, and 14.5% (2034) by staged excision. Local recurrence rates were lowest for MMS (0.61%; 95% CI, 0.1%-1.4%), followed by staged excision (1.8%; 95% CI, 1.0%-2.9%) and WLE (7.8%; 95% CI, 6.4%-9.3%).

LIMITATIONS

Definitions of local recurrence varied. Surgical techniques included varying proportions of invasive melanomas. Studies had heterogeneity.

CONCLUSION

Systematic review and meta-analysis show lower local recurrence rates for cutaneous head and neck melanoma after treatment with MMS or staged excision compared to WLE.

Systematic Review of the Role of Mohs Micrographic Surgery in the Management of Early-Stage Melanoma of the Head and Neck

BACKGROUND

The role of Mohs micrographic surgery (MMS) in the management of melanoma of the head and neck (HNM) has been controversial. The authors systematically reviewed the local recurrence rate of melanoma in situ (MIS) and T1a melanomas using MMS compared with conventional wide local excision (WLE) and staged excision (SE).

OBJECTIVE

To systematically review the local recurrence rate of early-stage melanomas of the HNM treated with MMS versus WLE or SE.

METHODS AND MATERIALS

A search of English medical literature was conducted through the common databases until November 26, 2019. Using PRISMA guidelines for the treatment of MIS and T1a melanoma with MMS, WLE, or SE, our search yielded a total of 32 articles.

RESULTS

Mohs micrographic surgery has a lower local recurrence rate for early-stage melanomas over both SE and WLE {pooled recurrence risk 0.8% (95% confidence interval [CI] 0.4-1.1) versus 2.5% (95% CI 1.5-3.4) versus 8.7% (95% CI 5.1-12.2) (p < .001), respectively}.

CONCLUSION

Mohs micrographic surgery may offer a lower recurrence rate than SE or WLE in the management of early-stage melanomas of the face or HNM. Further clinical validation in a randomized controlled trial is required.

Compliance with sentinel lymph node biopsy guidelines for invasive melanomas treated with Mohs micrographic surgery

BACKGROUND

Sentinel lymph node biopsy (SLNB) has not been studied for invasive melanomas treated with Mohs micrographic surgery using frozen-section MART-1 immunohistochemical stains (MMS-IHC). The primary objective of this study was to assess the accuracy and compliance with National Comprehensive Cancer Network (NCCN) guidelines for SLNB in a cohort of patients who had invasive melanoma treated with MMS-IHC.

METHODS

This retrospective cohort study included all patients who had primary, invasive, cutaneous melanomas treated with MMS-IHC at a single academic center between March 2006 and April 2018. The primary outcomes were the rates of documenting discussion and performing SLNB in patients who were eligible based on NCCN guidelines. Secondary outcomes were the rate of identifying the sentinel lymph node and the percentage of positive lymph nodes.

RESULTS

In total, 667 primary, invasive, cutaneous melanomas (American Joint Committee on Cancer T1a-T4b) were treated with MMS-IHC. The median patient age was 69 years (range, 25-101 years). Ninety-two percent of tumors were located on specialty sites (head and/or neck, hands and/or feet, pretibial leg). Discussion of SLNB was documented for 162 of 176 (92%) SLNB-eligible patients, including 127 of 127 (100%) who had melanomas with a Breslow depth >1 mm. SLNB was performed in 109 of 176 (62%) SLNB-eligible patients, including 102 of 158 melanomas (65%) that met NCCN criteria to discuss and offer SLNB and 7 of 18 melanomas (39%) that met criteria to discuss and consider SLNB. The sentinel lymph node was successfully identified in 98 of 109 patients (90%) and was positive in 6 of those 98 patients (6%).

CONCLUSIONS

Combining SLNB and MMS-IHC allows full pathologic staging and confirmation of clear microscopic margins before reconstruction of specialty site invasive melanomas. SLNB can be performed accurately and in compliance with consensus guidelines in patients with melanoma using MMS-IHC.

Comparison of photoacoustic imaging and histopathological examination in determining the dimensions of 52 human melanomas and nevi ex vivo

Surgical excision followed by histopathological examination is the gold standard for the diagnosis and staging of melanoma. Reoperations and unnecessary removal of healthy tissue could be reduced if non-invasive imaging techniques were available for presurgical tumor delineation. However, no technique has gained widespread clinical use to date due to shallow imaging depth or the absence of functional imaging capability. Photoacoustic (PA) imaging is a novel technology that combines the strengths of optical and ultrasound imaging to reveal the molecular composition of tissue at high resolution. Encouraging results have been obtained from previous animal and human studies on melanoma, but there is still a lack of clinical data. This is the largest study of its kind to date, including 52 melanomas and nevi. 3D multiwavelength PA scanning was performed ex vivo, using 59 excitation wavelengths from 680 nm to 970 nm. Spectral unmixing over this broad wavelength range, accounting for the absorption of several tissue chromophores, provided excellent contrast between healthy tissue and tumor. Combining the results of spectral analysis with spatially resolved information provided a map of the tumor borders in greater detail than previously reported. The tumor dimensions determined with PA imaging were strongly correlated with those determined by histopathological examination for both melanomas and nevi.

Outcomes of mohs microgrpahic resection for cutaneous malignancy involving the scrotum

INTRODUCTION

Squamous cell carcinoma (SCC) and extramammary Paget's Disease (EMPD) of the scrotum are exceedingly rare. Given their propensity for local invasion and treatment with wide local excision, they can be highly morbid conditions. Outcomes of Mohs Micrographic Surgery (MMS) for scrotal cutaneous malignancy is not well described in current literature. We hypothesized that MMS for scrotal cutaneous malignancy would provide equivalent or improved oncologic outcomes while limiting the morbidity associated with wide excision.

MATERIALS/METHODS

This is a retrospective review and analysis of a prospectively maintained database spanning entries from 2005 to 2019. Collected data included general patient characteristics and surgical characteristics reported on a per lesion basis. MMS was performed by our institution's department of dermatology using their standard technique.

RESULTS

Overall, a total of 26 consecutive patients with 28 lesions (SCC or EMPD) were analyzed. Out of our cohort of 15 patients with 16 scrotal SCC lesions, 10 (66%) patients were current or former smokers, 4 (26%) were immunosuppressed, and 2 (13%) had HPV infections. The median preoperative and postoperative size of SCC lesions were 5.7cm [2] and 20.2cm [2] respectively. There was one (6%) oncologic recurrence of SCC of the scrotum and one (6%) local wound complication. Our cohort also included 11 patients with 12 scrotal EMPD lesions. One patient (9%) had an underlying associated malignancy (prostate cancer). The preoperative and postoperative area of lesions were 50.6cm [2] and 96.4cm [2] respectively. One (9%) EMPD lesion had a positive final margin at resection requiring reoperation. After achieving negative surgical margins, no patients in this cohort had an oncologic recurrence. 3 (26%) scrotal EMPD cases had local wound postoperative complications, only one required reoperation.

CONCLUSION

To our knowledge, this is the first case series focused on MMS for both SCC and EMPD with scrotal involvement. Our data suggests that MMS for scrotal cutaneous malignancy may improve oncologic outcomes and may decreases local post-operative reconstructive issues when compared to reported outcomes of treatment with wide local excision. When able, scrotal cutaneous malignancy patients should be referred to urologists at centers with MMS capabilities as it likely will improve their outcomes. The urologist should maintain active involvement with these patients to coordinate this complex and advanced pattern of care.

Mohs micrographic surgery: a review of indications, technique, outcomes, and considerations

Mohs micrographic surgery is a specialized form of skin cancer surgery that has the highest cure rates for several cutaneous malignancies. Certain skin cancers can have small extensions or “roots” that may be missed if an excised tumor is serially cross-sectioned in a “bread-loaf” fashion, commonly performed on excision specimens. The method of Mohs micrographic surgery is unique in that the dermatologist (Mohs surgeon) acts as both surgeon and pathologist, from the preoperative considerations until the reconstruction. Since Dr. Mohs’s initial work in the 1930s, the practice of Mohs micrographic surgery has become increasingly widespread among the dermatologic surgery community worldwide and is considered the treatment of choice for many common and uncommon cutaneous neoplasms. Mohs micrographic surgery spares the maximal amount of normal tissue and is a safe procedure with very few complications, most of them managed by Mohs surgeons in their offices. Mohs micrographic surgery is the standard of care for high risks basal cell carcinomas and cutaneous squamous cell carcinoma and is commonly and increasingly used for melanoma and other rare tumors with superior cure rates. This review better familiarizes the dermatologists with the technique, explains the difference between Mohs micrographic surgery and wide local excision, and discusses its main indications.

Association of Mohs Micrographic Surgery vs Wide Local Excision With Overall Survival Outcomes for Patients With Melanoma of the Trunk and Extremities

Importance

Although previous database studies suggest that Mohs micrographic surgery (MMS) treatment is associated with improved overall survival (OS) for head and neck melanomas, outcomes for trunk and extremity (T&E) tumors have not been adequately evaluated.

Objective

To assess survival outcomes for patients with melanomas of the T&E treated with MMS vs wide local excision (WLE).

Design, Setting, and Participants

This retrospective cohort study examined deidentified data from the National Cancer Database between 2004 and 2015. Inclusion criteria for the analysis included diagnosis of trunk, upper extremity, or lower extremity melanoma; known Breslow depth; removal by MMS or WLE; and known last date of survival status.

Main Outcomes and Measures

Five-year all-cause mortality (ACM) rates.

Results

A total of 188 862 in situ and invasive melanomas were included in the analysis (MMS, 2.3%; WLE, 97.7%); the mean (SD) age of patients included was 58.8 (16.0) years, and 52.7% were male. Multivariate analysis demonstrated no OS difference among trunk (WLE hazard ratio [HR], 1.097; 95% CI, 0.950-1.267; P = .21), upper extremity (WLE HR, 1.013; 95% CI, 0.872-1.176; P = .87), lower extremity (WLE HR, 0.934; 95% CI, 0.770-1.134; P = .49), or combined T&E (WLE HR, 1.031; 95% CI, 0.941-1.130; P = .51) tumors. Factors associated with increased risk of ACM on multivariate analysis of all tumors included increasing age (HR, 1.043; 95% CI, 1.042-1.044; P < .001), no insurance or nonprivate insurance (none: HR, 1.921 [95% CI, 1.782-2.071]; Medicaid: HR, 2.410 [95% CI, 2.242-2.591]; Medicare: HR, 1.237 [95% CI, 1.194-1.281]; other government insurance: HR, 1.279 [95% CI, 1.117-1.465]; P < .001 for all), positive surgical margins (HR, 1.609; 95% CI, 1.512-1.712; P < .001), a Charlson-Deyo comorbidity score greater than 0 (Charlson-Deyo score of 1: HR, 1.340; 95% CI, 1.295-1.385; P < .001; Charlson-Deyo score of ≥2: HR, 2.044; 95% CI, 1.934-2.159; P < .001), tumor ulceration (HR, 2.175; 95% CI, 2.114-2.238; P < .001), and increasing Breslow depth (HR, 1.002 [per 0.1 mm]; P < .001). Female sex (HR, 0.698; 95% CI, 0.680-0.716; P < .001) and nonnodular subtype (lentigo maligna/lentigo maligna melanoma: HR, 0.743; 95% CI, 0.686-0.805; P < .001; superficial spreading: HR, 0.739; 95% CI, 0.710-0.769; P < .001; other subtype: HR, 0.817; 95% CI, 0.790-0.845; P < .001; nodular: HR, 1 [reference]) were associated with improved OS.

Conclusions and Relevance

This cohort study of patients surgically treated for melanomas of the trunk and/or extremities found that, compared with WLE, MMS was not associated with significantly different OS for T&E melanomas.

Lentiginous melanoma (lentigo maligna and lentigo maligna melanoma) in Australia: clinicopathological characteristics, management and recurrence rates after 10-year follow-up at a tertiary centre

BACKGROUND

Lentiginous melanoma or lentigo maligna is a slow-growing type of melanoma frequently arising in sun-damaged skin and often first diagnosed in the elderly. Few studies report long-term follow-up.

OBJECTIVES

To define characteristics of lentiginous melanoma in situ (LM) and invasive lentiginous melanoma (LMM) in Australian patients managed at a tertiary centre and describe local recurrence or treatment failure rates after long-term follow-up.

METHODS

Retrospective single-centre study of LM/LMM patients evaluated between January 2005 and March 2007. Medical and photographic records were reviewed.

RESULTS

One hundred two patients were included, with a total of 117 lesions (70 LM and 47 LMM). Seventy-nine were new primary LM/LMM, and 38 were recurrences. Primary cases were mostly pigmented (71%), while 77% of recurrent cases were partially pigmented/light brown or amelanotic. The margins were clinically ill-defined in the majority of cases (64% of primary cases and 94% of recurrent cases). Dermoscopy of the primary LM/LMM showed either classic 'common' melanoma features (33%) or classic LM/LMM features (41%), while 95% of recurrent cases had no features for melanoma or LM/LMM. Primary cases that were initially excised (113, 97%) had mean histopathological clear margins of 4.9 mm (range 0.1-22 mm). The median follow-up time was 7.5 years (95% CI 5.2-10.0) with more than 10-year follow-up in 32% and 5-10 years in 24% of patients. There were 44 (38%) recurrences over the entire follow-up period. Half of the patients who recurred did so within the first 3.8 years after the first treatment.

CONCLUSION

LM/LMM often recur late and are clinically subtle; therefore, careful monitoring and long-term follow-up are required.

Management of Nail Unit Melanoma

Nail unit melanoma is an uncommon form of melanoma with worse prognosis compared with nonacral cutaneous melanoma. Nail unit melanoma is often diagnosed at a late stage. Clinical and dermoscopic features may suggest a diagnosis of nail unit melanoma, but confirmation requires histologic analysis. Like the clinical diagnosis, histopathologic diagnosis of nail unit melanoma is also difficult. The surgical management of nail unit melanoma has evolved from aggressive amputations to digit-sparing approaches. This article reviews the clinical presentation, diagnosis, and surgical treatment of nail unit melanoma to promote early diagnosis and rational surgery.

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.

Invasive Melanoma and Melanoma in Situ Treated With Modified Mohs Micrographic Surgery With En Face Permanent Sectioning: A 10-Year Retrospective Review

BACKGROUND

Successful surgical treatment of cutaneous melanoma is dependent on margin control.

OBJECTIVE

To determine efficacy of modified Mohs micrographic surgery (mMMS) with en face permanent margins in management of invasive melanoma (IM) and melanoma in situ (MIS).

METHODS

A retrospective cohort study evaluating local recurrence, 5-year recurrence-free survival, and 5-year melanoma-specific survival. Overall, 657 melanomas (128 IM and 529 MIS) from 631 patients were treated using mMMS during a 10-year period. Follow-up information was obtained from medical records and telephone encounters.

RESULTS

The median follow-up time was 5.18 years. Most melanomas were located on the head and neck 93.6% (615/657). Margins required for clearance were 0.77 ± 0.44 cm (mean ± SD). Local recurrence was identified in 1.98% (13/657) of melanomas with no local recurrences in IM. Five-year local recurrence-free and melanoma-specific survival rates were estimated to be 96.9% (95% confidence interval [CI]: 94.6%-98.2%) and 99.0% (95% CI: 97.7%-99.6%). There were 5 melanoma-related deaths.

CONCLUSION

Modified Mohs micrographic surgery is an effective treatment of melanoma as evidenced by low local recurrence rates and high melanoma-specific survival.