Lentigo Maligna Research Articles

Cutaneous melanoma in situ: a review.

Cutaneous melanoma in situ (MIS), also known as 'stage 0 melanoma', is a collection of malignant melanocytes in the epidermis and epithelial adnexa, without evidence of microinvasion to the papillary dermis. Distinct histologic subtypes include lentigo maligna (LM), superficial spreading (SS) MIS and acral lentiginous (AL) MIS. LM is the most common subtype, usually diagnosed later in life (median age at diagnosis of 66-72 years) and associated with cumulative ultraviolet radiation exposure. SS MIS is associated with intense episodes of sun exposure and is more common on the trunk and extremities. AL MIS is seen in non-hair-bearing skin. Although rare (0.6% of MIS in England), AL MIS is found in higher proportion in more pigmented skin types compared to other MIS subtypes. Most international studies between 1990-2019 report rising incidence for MIS. US data support a deceleration in the rising incidence of LM between 2016-2019. For 2013-2019 in England, the recorded incidence of LM is plateauing, while that of other MIS is rising. Definitive diagnosis of MIS is by histological examination of biopsied skin with immunohistochemistry but can be supported with dermoscopy and reflectance confocal microscopy. Surgical treatment (excision or Mohs micrographic surgery) is the gold standard. Depending on MIS subtype, other options such as cryotherapy, topical imiquimod, radiotherapy, or watchful waiting may be appropriate. The latest 5-year net survival rates in England between 2013-2015 are 98.6% for AL MIS and exceed 100% for all other MIS. This review summarises the aetiology, pathogenesis, epidemiology, diagnosis and management of MIS.

Epidemiological, clinical and histological characteristics of melanoma in young adults: a 30-year retrospective study (1993-2022).

Melanoma in young adults significantly impacts the survival of this age group. There are limited studies that analyze melanoma characteristics in young patients. We aimed to describe the epidemiological, clinical, and histological characteristics of melanoma in young adults and their temporal trends over the last decades. A retrospective observational study was conducted, involving 399 melanoma patients aged 18-44, over a 30-year period (1993-2022). Patients were divided into two groups based on their date of diagnosis (period 1, 1993-2007, and period 2, 2008-2022). Age at diagnosis was higher in the most recent period (34.3 vs 37; p=0.001). Over time, there was a reduction in thickness (1 vs 0.68 mm; p=0.01), a rise in melanomas located on the head and neck (6.5% vs 14.8%) and extremities (42.2% vs 45%), along with a decrease on the trunk (51.3% vs 40.2%) (p=0.009); and an increase in lentigo maligna (2.3% vs 5.3%) and superficial spreading melanomas (76.5% vs 84%), along with reduction in nodular types (16.1% vs 5.9%) (p=0.012). Women had, compared to men, higher limb melanoma prevalence (56.3% vs 27.1%; p<0.001), family history (11.7% vs 5.1%; p=0.020), lower thickness (0.69 vs 1.10; p= 0.001) and better prognosis (14.4% vs 20.9% deaths; p=0.012). Melanoma diagnoses in young adults occur at progressively advanced ages, with a rise in melanomas situated on the head and extremities and in histological types linked to prolonged sun exposure. Strategies like minimizing sun exposure from a young age and encouraging self-examination could lead to improved survival rates.

Comparative Analysis of AI Models for Atypical Pigmented Facial Lesion Diagnosis.

Diagnosing atypical pigmented facial lesions (aPFLs) is a challenging topic for dermatologists. Accurate diagnosis of these lesions is crucial for effective patient management, especially in dermatology, where visual assessment plays a central role. Incorrect diagnoses can result in mismanagement, delays in appropriate interventions, and potential harm. AI, however, holds the potential to enhance diagnostic accuracy and provide reliable support to clinicians. This work aimed to evaluate and compare the effectiveness of machine learning (logistic regression of lesion features and patient metadata) and deep learning (CNN analysis of images) models in dermoscopy diagnosis and the management of aPFLs. This study involved the analysis of 1197 dermoscopic images of facial lesions excised due to suspicious and histologically confirmed malignancy, classified into seven classes (lentigo maligna-LM; lentigo maligna melanoma-LMM; atypical nevi-AN; pigmented actinic keratosis-PAK; solar lentigo-SL; seborrheic keratosis-SK; and seborrheic lichenoid keratosis-SLK). Image samples were collected through the Integrated Dermoscopy Score (iDScore) project. The statistical analysis of the dataset shows that the patients mean age was 65.5 ± 14.2, and the gender was equally distributed (580 males-48.5%; 617 females-51.5%). A total of 41.7% of the sample constituted malignant lesions (LM and LMM). Meanwhile, the benign lesions were mainly PAK (19.3%), followed by SL (22.2%), AN (10.4%), SK (4.0%), and SLK (2.3%). The lesions were mainly localised in the cheek and nose areas. A stratified analysis of the assessment provided by the enrolled dermatologists was also performed, resulting in 2445 evaluations of the 1197 images (2.1 evaluations per image on average). The physicians demonstrated higher accuracy in differentiating between malignant and benign lesions (71.2%) than in distinguishing between the seven specific diagnoses across all the images (42.9%). The logistic regression model obtained a precision of 39.1%, a sensitivity of 100%, a specificity of 33.9%, and an accuracy of 53.6% on the test set, while the CNN model showed lower sensitivity (58.2%) and higher precision (47.0%), specificity (90.8%), and accuracy (59.5%) for melanoma diagnosis. This research demonstrates how AI can enhance the diagnostic accuracy in complex dermatological cases like aPFLs by integrating AI models with clinical data and evaluating different diagnostic approaches, paving the way for more precise and scalable AI applications in dermatology, showing their critical role in improving patient management and the outcomes in dermatology.

A Review of Melanoma Subtypes: Genetic and Treatment Considerations.

Melanoma affects over one million people in the United States. This review explores genetic mutations and markers of all seven subtypes. Current treatment options and prognosis of each subtype are also discussed. For lentigo maligna, spitzoid, and nodular subtypes, BRAF was the most common mutation reported. For superficial spreading, TP53 was the most common. Acral lentiginous demonstrated CCDN1 and desmoplastic NF1 most frequently. No mutations have been identified in the nevoid subtype. Nodular melanoma is the deadliest subtype. Evidence suggests that the subtypes differ in regard to genetic markers/mutations, treatment and prognosis. Therefore, subtype should be considered when treating a melanoma patient.

Incomplete Excision Rate for Lentigo Maligna and Associated Risk Factors.

Standard treatment for lentigo maligna (LM) is surgical excision, yet insights into the frequency of and risk factors for incomplete excisions remain limited. The primary objectives were to assess the incomplete excision rate (IER) in primary LM and to explore potential risk factors for incomplete excisions. A retrospective analysis was conducted encompassing consecutive histopathologically confirmed LMs from 2014-2020. Descriptive statistics were used for LM characteristics and IER, while uni- and multivariate analyses were used for calculating risk factors. The study included 395 LMs with an IER of 16.7% (n = 66). Risk factors for higher incomplete excision rates included: head and neck lesions (p = 0.0014), clinical excision margins < 5 mm (p = 0.040), and utilization of preoperative partial biopsies (p = 0.023). Plastic surgeons had higher IERs than dermatologists (p = 0.036). Lesion diameter (p = 0.20) and surgeon experience (p = 0.20) showed no associations with incomplete excisions, yet LMs with a diameter ≥ 20 mm exhibited higher incomplete excision rates (23.2%) compared witho those < 10 mm (12.9%). LMs should be excised with at least 5-mm clinical margins, especially in the head and neck area. LMs ≥ 20 mm may be more surgically challenging. High-er incomplete excision rates associated with the use of preoperative biopsies and/or plastic surgeons may reflect challenging anatomical locations, larger lesion diameter, and/or ill-defined borders.

Lentigo Maligna and Lentigo Maligna Melanoma of the External Ear: Clinical and Dermoscopic Features of 19 Patients.

External ear lentigo maligna/lentigo melanoma (LM/LMM) represents approximately 1%-4% of all primary cutaneous melanomas. Over the past 20 years, dermoscopy has proven highly effective in early detection of LM/LMM, with recent studies identifying perifollicular linear projections (PLP) as a specific diagnostic criterion for early LM. However, in clinical practice, LM and LMM turn out to be very difficult to distinguish based on dermoscopic findings. Therefore, our retrospective monocentric study aimed to investigate dermoscopic characteristics, as well as the epidemiological and clinical data of 19 patients diagnosed with the external ear (EE) LM/LMM at the Oncologic Dermatology Unit in Bologna. Dermoscopic images were obtained using the FotoFinder Medicam 800HD, and specific criteria validated by the International Dermoscopy Society (IDS) for atypical pigmented facial lesions were assessed. Fisher's exact test was primarily used for statistical comparisons. As results, most of the patients were male (74%) with an average age (± SD) at diagnosis of 69.8 (± 15.1) years old. LMM appeared more commonly observed in elderly patients as compared to LM (mean 71.6 vs. 66.7, p = 0.514), presenting as pigmented macule (89.5%) of the ear lobule (23.9%). A statistically significant difference (p = 0.01) of tumour' diameter between LMM and LM was reported with the first resulting more than twice the size of the latter. Concerning dermoscopic findings, asymmetric pigmented follicles, obliteration of the follicular openings and grey circles were more frequently observed in LMM compared to LM (63.2% vs. 31.6%; 63.2% vs. 26.3%; 47.4% vs. 15.8%, respectively).

Mohs Micrographic Surgery With Melanocytic Immunostains for T1a/b Invasive Melanoma Yields

The use of Mohs micrographic surgery with melanocytic immunostains (MMS-I) for cutaneous melanoma is increasing. To assess local recurrence, melanoma-specific death rates in patients with invasive melanoma treated with MMS-I. A single-center retrospective review of patients with invasive melanoma treated with MMS-I from January 2008 to December 2018. Three hundred fifty-two patients (359 melanomas) were included. The median age was 71 years; most patients were male (252%; 71.6%). Most tumors were T1a/b (341, 95%), H/N (322; 89.7%), and lentigo maligna subtype (281, 78.3%). At a median follow-up of 4.3 years, local recurrence rates were 1.4% (5) and 0.9% (3) among all-stage and T1a/b tumors, respectively. There were 3 melanoma-related deaths (0.9%). MMS-I is associated with <1% risk of local recurrence and disease-specific mortality for T1a/b melanomas.

Improved Disease-Specific Survival in Lentigo Maligna Treated with Mohs Surgery over Wide Local Excision: A Retrospective Cohort Analysis.

Lentigo maligna (LM), a subtype of melanoma in situ, typically occurs on sun-damaged skin of the head and neck in older men. Using the SEER database, the aim of this study was to compare disease-specific survival (DSS) outcomes between patients treated with wide local excision (WLE) and Mohs micrographic surgery (MMS), finding – on multivariable analysis – that MMS demonstrated improved 5- and 10-year DSS rates and a lower disease-specific mortality risk than WLE. Our findings highlight a potential DSS benefit of MMS for treating LM, although further research is required to confirm these findings and explore factors influencing treatment choices.

Dermoscopic Features and Algorithm- A Guide to Detecting Pre-Malignant Facial Pigmented Skin Lesions in Ethnic Skin

Introduction: Detection of pre malignant facial pigmented lesions on a photo damaged ethnic skin has been crucial for dermatologists in preventing malignant transformation. Facial Pigmented Skin Lesions (FPSLs) that render a diagnostic challenge include, Pigmented Actinic Keratosis (PAK), early Seborrheic Keratosis (SK), Solar Lentigo (SL) and Lentigo Maligna (LM). Dermatoscopy or epiluminescence microscopy, is skin surface microscopy that has demonstrated to be a non-invasive, in vivo, high yield technique to evaluate a pigmented macule for an atypical evolution. Objective: To establish dermatoscopic findings of clinically challenging FPSLs conforming PAK, SK, SL and LM and derive an Algorithm with diagnostic features for detecting Premalignant Facial Pigmented Skin Lesions. Subjects and Methods: We here in conducted a largest case study a cross-sectional analysis of clinically challenging 182 flat FPSLs, evaluated dermoscopic images consistent to pigmented AK, early SK, SL and LM and subsequently biopsied for histopathological evidence. Four major dermoscopic features were appraised: pigment pattern, sharp demarcation, vascular criteria and follicular/epidermal pattern. Study Design: Cross sectional validation-study Setting: Department of Dermatology Unit II, King Edward Medical University, Mayo Hospital Lahore. Study was conducted for a period of six months. Result: We derived an “Algorithm” elucidating diagnostic findings of FPSLs. Pigmented AK on dermoscopy has strawberry pattern in 42% of lesions (pink to red pseudo-network with erythematous background, prominent follicular ostia fenced by a white targetoid halo), while Sharp demarcation (57.15%) and follicular/epidermal pattern (cerebriform pattern 100% of lesions, milia-like cysts, 50%, and comedo-like openings 38.57%) are distinctively observed SK. In SL, homogenous structureless pigmentation is significant entirely (100%). However, in LM predominates pseudonetwork (89.47%), homogenous structureless pigmentation (78%) and vascular patterns while strawberry pattern is observed in (26.31%) of lesions. Conclusion Our “Dermoscopic Algorithm” constitutes diagnostic characteristics of “Facial Pigmented Skin Lesions,” that would not only aid in early corrective detection of clinically similar lesions with different biologic behavior, but serve the the purpose to prevent vigorous malignant transformation in photo damaged ethnic skin, particularly Lentigo Maligna turning into a potential Melanoma, Hence, Sharp demarcation with cribriform pattern is specific of Sebhorric Keratosis (SK), while homogenous structureless pigmentation without prominent vascular pattern is distinctive of Solar Lentigo (SL). Pigmented Actinic Keratosis (AK) is described by prominent strawberry pattern. Nonetheless, homogenous structureless pigmentation and vascular pattern with pseudonetwork are featured in Lentigo Maligna (LM), lacking of prominent strawberry pattern. Conflict of Interest: The Authors have no conflict of interest to disclose.

The use of Reflectance Confocal Microscopy to diagnose Malignant Melanoma and Lentigo Maligna in the United Kingdom: A Prospective Observational Trial at a Single Centre.

Previous work with Reflectance Confocal Microscopy (RCM) imaging has shown high sensitivity and specificity for Malignant Melanoma (MM), but to date there have been no studies on a UK cohort. The study hypothesised that RCM could be used prospectively to accurately diagnose MM and lentigo maligna (LM) in a private UK secondary care, single clinician setting. The study assessed the potential for RCM to be used as a routine screening procedure. 597 patients were recruited consecutively where MM or LM featured in the differential diagnosis after clinical examination. A sequential record was made of the clinical, dermoscopic, and RCM findings by a single dermatologist [HS] prior to biopsy. Imaging used the arm-mounted confocal microscope unless access was restricted and required the handheld probe. The likelihood of MM was scored for each modality, each diagnosis building on the last. Histology was assessed by a single blinded histopathologist [JJ]. 734 lesions were included in the analysis, including 86 MM and LM with a median diameter of 7.0 mm. The benign to malignant ratio was 3 to 1 (non-melanocytic malignancies included) and 8.3 to 1 for MM and LM only. The sensitivity and specificity for MM and LM was 62.8% (95% CI 51.70% to 72.98%) and 63.2% (59.27% to 66.84%) for clinical examination; 91.9% (83.95% to 96.66%) and 42.1% (38.14% to 45.88%) for dermoscopy; 94.2% (86.95% to 98.09%) and 83.2% (79.91% to 85.84%) for RCM. For RCM, PPV was 42.4% (38.13% to 46.81%) and NPV was 99.1% (97.87% to 99.60%). This study demonstrates that RCM can reliably diagnose MM and is fast enough to be integrated into UK pigmented lesion clinics by dermatologists trained in RCM. "Number needed to treat" dropped from 3.9 with clinical examination to 3.0 with dermoscopy to 1.3 with RCM.

Luz de Wood en dermatosis inflamatorias, autoinmunes, infecciones y cáncer cutáneo

Wood's light (WL) is a useful, economical and easy-to-learn diagnostic tool. Despite its advantages, the use of LW among dermatologists is limited. In porokeratosis, the “diamond necklace” sign has been described, corresponding to the white fluorescence of the hyperkeratotic scale. Subclinical morphea lesions are seen as well-defined dark macules. Among the pigmentary disorders, the bluish fluorescence of vitiligo, the increased contrast of epidermal melasma, and the follicular-centered red fluorescence of progressive macular hypomelanosis stand out. Regarding skin infections, erythrasma presents a coral red fluorescence; tinea versicolor, yellow-green fluorescence; Pseudomonas aeuriginosa, green fluorescence; and scabies, blue-white fluorescence in the acarine grooves. In skin cancer, LW has been used to delimit the surgical margins of both lentigo maligna and non-melanoma skin cancer, with variable results.

Frequency of BRAF Mutations in Dysplastic Nevi, Lentigo Maligna, and Melanoma In Situ.

Background: In melanomas, mutations in the BRAF gene are common and their occurrence represents an early oncogenic event. Our goal was to determine and compare the frequency of BRAF gene mutations in dysplastic nevi (ND) and melanomas in situ (MIS), as well as whether there is a correlation between the presence of BRAF gene mutations and various anamnestic, clinical, and histopathologic variables. Methods: A total of 175 patients-106 with ND, 41 with MIS, and 28 with lentigo maligna (LM) were included in the study. DNA was extracted from tissue samples and analyzed using the competitive allele-specific TaqMan chain reaction by polymerase in real time to detect the presence of BRAF V600E and V600K mutations. The data were compared with anamnestic, clinical, and histopathological data. Results: There is a statistically significant correlation between the presence of BRAF mutation and the diagnosis of melanoma in situ (χ2 test, χ2 = 29.17, p < 0.0001). Patients with LM had a significantly lower incidence of BRAF mutations compared to patients with ND and MIS. There was a significant correlation between the presence of a BRAF mutation and tumor localization, as well as the age of the patient, but no statistically significant correlation between the presence of a BRAF mutation and sex, tumor size, or previous melanoma diagnosis. Conclusions: BRAF mutations in ND are essentially required; however, they are an insufficient oncogenic trigger for the development of melanoma. This research contributes to a better understanding of the etiopathogenesis of melanoma and the role of ND as possible precursor lesions.

Comparison of Ophthalmologists versus Dermatologists for the Diagnosis and Management of Periorbital Atypical Pigmented Skin Lesions.

Background/Objectives: Lentigo maligna (LM) and lentigo maligna melanoma (LMM) are significant subtypes of melanoma, with an annual incidence of 1.37 per 100,000 people in the U.S. These skin tumors, often found in photo-exposed areas such as the face, are frequently misdiagnosed, leading to delayed treatment or unnecessary excisions, especially in the elderly. Facial melanocytic skin tumors (lentigo maligna-LM/lentigo maligna melanoma-LMM) and their simulators (solar lentigo, pigmented actinic keratosis, seborrheic keratosis and lichen planus-like keratosis) often affect the periocular region. Thus, their diagnosis and management can involve different medical figures, mainly dermatologists and ophthalmologists. This study aimed to evaluate the ability of ophthalmologists to diagnose and manage pigmented skin lesions of the periorbital area. Methods: A multicentric, retrospective, cross-sectional study on a dataset of 79 periorbital pigmented skin lesions with both clinical and dermoscopic images was selected. The images were reviewed by six ophthalmologists and two dermatologists. Descriptive statistics were carried out, and the accuracy, sensitivity, and specificity, with their 95% confidence interval (95% CI), were estimated. Results: Ophthalmologists achieved a diagnostic accuracy of 63.50% (95% CI: 58.99-67.85%), while dermatologists achieved 66.50% (95% CI: 58.5-73.8). The sensitivity was lower for ophthalmologists in respect to dermatologists, 33.3% vs. 46.9%, respectively. Concerning the case difficulty rating, ophthalmologists rated as "difficult" 84% of cases, while for dermatologists, it was about 30%. Management was also consistently different, with a "biopsy" decision being suggested in 25.5% of malignant lesions by ophthalmologists compared with 50% of dermatologists. Conclusions: Ophthalmologists revealed a good diagnostic potential in the identification of periorbital LMs/LMMs. Given progressive population ageing and the parallel increase in facial/periorbital skin tumors, the opportunity to train new generations of ophthalmologists in the early diagnosis of these neoformations should be considered in the next future, also taking into account the surgical difficulty/complexity of this peculiar facial area.

[Translated article] Dermoscopy of Squamous Cell Carcinoma: From Actinic Keratosis to Invasive Forms

When the dermoscopy of squamous cell carcinoma and its precursors we differentiate among keratin-related, vascular, and pigment-related criteria. Non-pigmented actinic keratoses are characterized by the “strawberry pattern”. Pigmented actinic keratosis shows a significant dermatoscopic overlap with lentigo maligna, but the presence of pigmented scales, erythema, and prominent follicles favors its diagnosis. Bowen's disease is characterized by clustered glomerular vessels, white-yellowish scales, and brown or grey dots arranged in lines in its pigmented variant. Finally, dermoscopy allows us to detect invasive squamous cell carcinoma in its early stages and differentiate it from its precursors. Furthermore, its presentation may vary depending on the degree of differentiation, with keratin-associated criteria predominating in well-differentiated tumors, while an atypical vascular pattern will predominate in poorly differentiated tumors.

Utilizing deep learning model for assessing melanocytic density in resection margins of lentigo maligna

BackgroundSurgical excision with clear histopathological margins is the preferred treatment to prevent progression of lentigo maligna (LM) to invasive melanoma. However, the assessment of resection margins on sun-damaged skin is challenging. We developed a deep learning model for detection of melanocytes in resection margins of LM.MethodsIn total, 353 whole slide images (WSIs) were included. 295 WSIs were used for training and 58 for validation and testing. The algorithm was trained with 3,973 manual pixel-wise annotations. The AI analyses were compared to those of three blinded dermatopathologists and two pathology residents, who performed their evaluations without AI and AI-assisted. Immunohistochemistry (SOX10) served as the reference standard. We used a dichotomized cutoff for low and high risk of recurrence (≤ 25 melanocytes in an area of 0.5 mm for low risk and > 25 for high risk).ResultsThe AI model achieved an area under the receiver operating characteristic curve (AUC) of 0.84 in discriminating margins with low and high recurrence risk. In comparison, the AUC for dermatopathologists ranged from 0.72 to 0.90 and for the residents in pathology, 0.68 to 0.80. Additionally, with aid of the AI model the performance of two pathologists significantly improved.ConclusionsThe deep learning showed notable accuracy in detecting resection margins of LM with a high versus low risk of recurrence. Furthermore, the use of AI improved the performance of 2/5 pathologists. This automated tool could aid pathologists in the assessment or pre-screening of LM margins.

Lentigo maligna: a comprehensive review on diagnosis and treatment.

Lentigo maligna (LM), a form of melanoma in situ, and LM melanoma (LMM), its invasive counterpart, exhibit distinctive epidemiology, risk factors, and clinical features compared to other melanoma subtypes. Notably, LM occurs on chronically sun-damaged skin presenting as a slow-growing, ill-defined patch which makes it difficult to diagnose and to treat. Additionally, while LM generally presents a favourable prognosis, it can also lead to dermal invasion and behave similarly to other melanomas with the same Breslow thickness. Hence, surgery continues to be the cornerstone treatment. Wide excisions are often necessary, but challenges arise when these lesions manifest in cosmetically sensitive regions, limiting the feasibility and desirability of large excisions. Specialized approaches, including margin-controlled surgery and image-guided treatment with reflectance confocal microscopy, have been developed to address these issues. Other non-surgical treatments such as cryosurgery, imiquimod, radiotherapy, or photodynamic therapy, may also be used but commonly present with recurrent/persistent disease. Herein we comprehensively review the existing literature on the management of LM/LMM, and discus the potential new advances on managing this challenging skin cancer.

Wound Healing Complications Associated with Staged Reconstruction after Facial Lentigo Maligna Resection.

Background: The rates and risk factors for wound complications following staged reconstruction after facial lentigo maligna (LM) resection have not been well described. Objectives: (1) To identify the rate and types of wound complications, including infection, graft necrosis, distal flap necrosis, hematoma, superficial epidermolysis, and seroma among patients undergoing staged reconstruction after resection of LM as documented in the surgeon's clinical notes within 30 days of the procedure. (2) To determine a threshold defect size that may predict the development of wound complications. Design and Outcomes: Retrospective review at an academic medical center of patients who underwent staged reconstruction after facial LM resection over a 5-year period. Results: Ninety-eight patients were identified with a mean age of 69.2 ± 13.6 years; 37% of patients were female. The most common defect sites were the cheek (n = 41; 42%) and nose (n = 22; 22%). Twenty-five of 98 patients (26%) demonstrated complications, with the most common being wound infection (36%) and graft necrosis (24%). Those receiving perioperative antibiotics had lower rates of complication (odds ratio [OR]: 0.36; 95% confidence interval [CI]: 0.13,0.96; p = 0.041). Defects greater than 2.7 cm in maximal diameter had the highest sensitivity for predicting complications. Conclusions: Patients undergoing staged reconstruction after facial LM resection have a high rate of wound complication (26%) and defect size > 2.7 cm may be an important risk factor.

Review of Tumor Margins for Lentigo Maligna with Staged Surgical Excision and Permanent Section en face Processing

Background: The optimal surgical margins required for the excision of lentigo maligna remains a topic of debate. Recent literature suggests that wider margins are warranted. Objective: Comparison of lentigo maligna margin sizes and clearance rates from a single center to existing literature. Methods: A retrospective analysis of primary and recurrent lentigo maligna treated by staged excision with complete circumferential and deep margin assessment between 2011 and 2023 at a single institution was conducted. The percentage of tumors with clear margins after the initial excision with 5 mm margins was determined. Results: A total of 65 tumors were identified. Fifty-eight patients (89.2%) had clear margins after initial excision with 5 mm margins. Conclusions: This study reports a higher percentage of lentigo maligna clearance following the initial staged excision with 5 mm margins than reports in the literature. These differences may be attributed to variations in section processing, staining techniques, and factors associated with differences in subclinical spread.

Enhanced disease-specific survival in lentigo maligna melanoma patients treated with Mohs surgery over wide local excision: A retrospective cohort analysis of the Surveillance, Epidemiology, and End Results database

Enhanced disease-specific survival in lentigo maligna melanoma patients treated with Mohs surgery over wide local excision: A retrospective cohort analysis of the Surveillance, Epidemiology, and End Results database

Successful implementation of handheld reflectance confocal microscopy as the standard of care in the (surgical) management of lentigo maligna (melanoma).

Reflectance confocal microscopy (RCM) has shown promise in predicting surgical outcomes by non-invasively detecting subclinical lentigo maligna (melanoma) (LM/LMM). To assess the effects of presurgical mapping using handheld RCM (HH-RCM) on surgical treatment, follow-up outcomes and management decisions. A total of 117 consecutive LM/LMM cases (2015-2023) were included. The diagnostic accuracy of HH-RCM in detecting subclinical LM and invasive components was evaluated. The primary endpoints included histological margin status and changes in management based on the outcomes of the HH-RCM mapping procedure. Margin and follow-up outcomes were compared to a historical cohort before HH-RCM was introduced in our center (n = 94) (2003-2014). HH-RCM detected subclinical LM in 60% (n = 60) of cases. The median mapping duration was 14 min (range 4-50). In 27% (n = 33), the mapping procedure resulted in modified management, the majority consisting of limited surgery with adjuvant imiquimod (n = 15) or imiquimod monotherapy (n = 14). The remaining cases (n = 84) underwent HH-RCM-assisted surgery. Histological margins were cleared in 96.5% of the patients with a median histological margin of 3.0 mm, significantly higher than 81% in the historical cohort (median 2.0 mm) (p = 0.001). The sensitivity and specificity for detecting the extent of subclinical LM were 94% (95% CI 80.4-99.3) and 84% (95% CI 70.3-92.7), respectively. The negative predictive value for the detection of LMM was 94% (95% CI 84.4-97.7), and 75% of the initially missed LMM (n = 12) were identified during the HH-RCM mapping procedure. The study cohort had a 1.6% local recurrence rate compared with 25% in the historical cohort. Integrating HH-RCM as the standard of care could lead to more personalized treatment strategies for LM/LMM and allows for the selection of patients suitable for nonsurgical treatment.