Diagnosis and Management of Acral Pigmented Lesions

BACKGROUND

Survival outcomes in acral lentiginous melanoma (ALM) are worse than for cutaneous melanoma. Diagnostic delays are believed to contribute to worse outcomes in ALM, including advanced-stage disease at initial presentation. Acral lentiginous melanoma, especially in its early stages, may be difficult to discern from benign pigmented acral lesions.

OBJECTIVE

The purpose of this article is to provide a comprehensive review of the diagnosis and management of acral pigmented lesions.

MATERIALS AND METHODS

A literature review was performed. The outcomes included were the clinical and dermoscopic features and the management frameworks and considerations for acquired and congenital melanocytic nevi, acral melanosis, nonmelanocytic pigmented lesions, and ALM.

RESULTS

Original research studies were primarily included. The use of dermoscopy, such as the 3-step algorithm and blotch (irregular), ridge pattern (parallel), asymmetry of structures, asymmetry of colors, furrow pattern (parallel), fibrillar pattern (BRAAFF) checklist, increases the diagnostic accuracy of acral pigmented lesions with high specificity and sensitivity. Short-term digital dermoscopic surveillance can be used to manage acral lesions, and histopathology should be collected when there is a concern for ALM.

CONCLUSION

The use of dermoscopy and an understanding of how to manage acral lesions may limit the number of biopsies performed on the acral skin, decrease the time to diagnosis, and facilitate early detection of ALM.

Dermoscopic features of neoplasms in skin of color: A review

BACKGROUND

Dermoscopy is undoubtedly a useful tool to improve diagnostic accuracy and minimize the number of unnecessary biopsies. However, much of the literature on dermoscopy focuses on findings in lighter-skin phototypes, leaving potential gaps of knowledge regarding its use in skin of color (SoC). As the clinical applications of dermoscopy continue to increase, understanding dermoscopic patterns in SoC is imperative.

OBJECTIVE

This review discusses the literature on dermoscopic findings of neoplasms in SoC, highlighting unique and characteristic dermoscopic features.

METHODS

A literature review was performed using the PubMed database. Case reports, case series, case-control studies, and systematic reviews were included.

RESULTS

A total of 8326 studies were identified based on the selected search terms, and 41 were included in this review based on relevance.

CONCLUSION

There are specific dermoscopic characteristics in SoC for benign nevi, acral lentiginous melanoma, ethnic melanonychia, and dermatofibroma; however, there is a lack of published data about specific features of cutaneous melanoma, subungual melanoma, pigmented basal cell carcinoma, and pigmented squamous cell carcinoma in SoC. Because pigmented basal cell carcinoma, pigmented squamous cell carcinoma, ethnic melanonychia, and acral lentiginous melanoma are diagnosed at later stages in this population, it is important to understand their dermoscopic features. Further descriptive studies are needed to better characterize unique dermoscopic features in neoplasms in SoC.

Dermoscopic characteristics of acral melanocytic nevi in children and adolescents

BACKGROUND/OBJECTIVE

There are limited data on the dermoscopic characteristics of acral nevi in the population under 18 years old. Our aim was to determine the frequency of acral volar nevi in children and adolescents, characterize their dermoscopic patterns, and identify relationships with age and location.

METHODS

We prospectively examined the palms and soles of 1319 patients presenting to our outpatient clinic from July 2018 to April 2019.

RESULTS

Acral volar nevi were observed in 28% of the children and adolescent population included in the study. A total of 474 nevi from 365 patients were examined. The presence of nevi increased with age. The most common dermoscopic pattern was parallel pigmented furrows, detected in 57.8% of nevi. The other patterns observed were combination (14.1%), fibrillar (10.1%), and latticelike (8.8%). The parallel furrow and globulostreak-like patterns were more common on the palms, whereas the fibrillar and combination patterns were more frequently seen on the plantar surfaces. While the frequency of the parallel pigmented furrow pattern did not differ between the 0- to 12-year and 13- to 18-year age-groups, the dotted variants of the parallel furrow were observed more frequently in the 0- to 12-year-olds (58.2%) than in the 13- to 18-year-olds (41.7%). A combination pattern and its most common variant, parallel furrow + crista dotted pattern, were detected at a significantly higher rate in the 0- to 12-year group (22.1% and 16.3%, respectively) compared to the 13- to 18-year group (11.4% and 6%, respectively).

CONCLUSIONS

Acral melanocytic nevi are common in children and adolescents, and their dermoscopic patterns may be associated with anatomic localization and age.

Clinical and Histopathologic Characteristics of Melanocytic Lesions on the Volar Skin Without Typical Dermoscopic Patterns

Importance

It is challenging to differentiate melanoma from melanocytic nevus on the volar skin in the absence of typical dermoscopic patterns.

Objective

To identify the frequency and clinical and dermoscopic characteristics of melanocytic lesions on the volar skin not displaying a parallel furrow pattern, lattice-like pattern, fibrillar pattern, or parallel ridge pattern on results of dermoscopy.

Design, Setting, and Participants

In this retrospective cohort study, a total of 504 melanocytic lesions on the volar skin were evaluated in the Shinshu University Hospital department of dermatology between January 1, 2000, and December 31, 2012. Dermoscopic images were independently assessed by 3 dermoscopists for the presence of established dermoscopic criteria. Statistical analysis was performed from October 1, 2017, to April 30, 2018.

Main Outcomes and Measures

Frequency of dermoscopic criteria and corresponding clinical (patient age and size and location of lesion) and histopathologic features.

Results

Of 504 lesions, 110 (21.8%) (melanocytic nevus, 97; melanoma, 8; and equivocal melanocytic lesion, 5) from 108 patients (68 female and 40 male patients; mean age, 40.1 years [range, 1-86 years]) did not show a parallel furrow pattern, lattice-like pattern, fibrillar pattern, or parallel ridge pattern. Among them, the mean patient age was significantly higher for melanoma than for melanocytic nevus (65.3 vs 38.0 years; P < .001), as was mean maximum lesion diameter (11.8 vs 5.7 mm; P < .001). Melanomas and equivocal melanocytic lesions tended to be distributed on weight-bearing areas of the foot sole, such as the heel, while nevi were spread over non-weight-bearing regions. Dermoscopically, 95 melanocytic nevi (97.9%) were symmetrical in 1 or 2 axes while melanomas were not. A total of 91 melanocytic nevi (93.8%) had 1 or 2 colors per lesion, and 4 melanomas (50.0%) had more than 2 colors. Vascular structures were seen in 3 melanocytic nevi (3.1%) and 3 melanomas (37.5%). Blue-white structures were seen in 18 melanocytic nevi (18.6%) and 3 melanomas (37.5%). Dots and globules were seen in 22 melanocytic nevi (22.7%) and 4 melanomas (50.0%). Vascular structures, blue-white structures, and dots and globules were irregularly distributed in the melanomas. Ulcer, hyperkeratosis, and irregular streaks were observed only in melanomas.

Conclusions and Relevance

More than one-fifth of melanocytic lesions on the volar skin did not display typical dermoscopic patterns. Asymmetry, numerous colors (≥3), and other melanoma-specific dermoscopic findings were more frequently observed for melanomas. Clinical information, including patient age and lesion size and location, was helpful in differentiating melanoma from melanocytic nevus. Further prospective clinical studies are warranted to clarify the diagnostic accuracy of dermoscopy combined with clinical information.

Comparison of dermoscopic features between congenital and acquired acral melanocytic nevi in Korean patients

BACKGROUND

The dermoscopic patterns of acral melanocytic nevi (AMNs) are crucial in differentiating them from acral melanoma. Several studies have reported the dermoscopic patterns of acquired acral melanocytic nevi (AAMNs). However, few have investigated the dermoscopic patterns of congenital acral melanocytic nevi (CAMNs).

OBJECTIVE

To compare the clinical and dermoscopic features of CAMNs and AAMNs.

METHODS

The present study included 43 patients with CAMNs and 40 with AAMNs. We reviewed their medical records as well as their clinical and dermoscopic findings.

RESULTS

Congenital acral melanocytic nevis were more asymmetrical than AAMNs (P = 0.002) and presented more frequently as comma-shaped (P = 0.005). Regarding dermoscopic findings, globular pattern (55.8%) was the most common feature of CAMNs, while parallel furrow pattern (37.5%) was the most common feature of AAMNs. The presence of fibrillar, globular, and parallel ridge patterns, and diffuse multi-component pigmentation differed significantly between the groups (P < 0.05). Furthermore, CAMNs showed melanoma-specific dermoscopic patterns, such as parallel ridge (18.6%) and diffuse multi-component pigmentation (25.6%).

CONCLUSION

The dermoscopic patterns of CAMNs and AAMNs differed markedly. In terms of dermoscopic patterns, CAMNs resembled acral melanoma more often than AAMNs did.

Juvenile melanocytic acral nevus: A comparative study between MANIAC and non-MANIAC nevus and its clinicopathological characteristics

BACKGROUND

Melanocytic acral nevi have a series of distinguishing features, including their location, patient age at onset, clinical progression, and histological findings. In particular, histopathological analysis often reveals a melanocytic acral nevus with intraepidermal ascent of cells (MANIAC nevus), which in some cases can be mistaken for atypia or malignancy.

AIM

This study describes the clinicopathological characteristics of acral nevi in patients under 18 years old and contrasts the clinical and histological features between MANIAC vs non-MANIAC nevi.

METHODS

This was a retrospective observational study, performed in our department in the decade between January 2007 and January 2017. We included patients younger than 18 years of age who were subjected to the removal of melanocytic acral nevi.

RESULTS

A total of 70 patients were studied. 54.2% (38/70) were females and 45.8% (32/70) were males. With regard to the type of nevus, 34 were compound, 27 were junctional, and 9 were predominantly intradermal lesions. We identified a total of 41 MANIAC nevi and 29 non-MANIAC nevi. Statistically significant differences between these two groups were identified in nevus size (larger in MANIAC) and the frequency of compound nevi (higher in the MANIAC group), but not in the remainder of the histological parameters studied.

Early detection of acral melanoma: A review of clinical, dermoscopic, histopathologic, and molecular characteristics

Acral lentiginous melanoma is a distinct subtype of melanoma on acral skin. Patient presentation at later stages and delayed diagnosis by physicians contribute to a worse associated prognosis and survival rate. Despite our progress in understanding the key features of this disease, the diagnosis of early-stage acral melanoma is still challenging. It is essential to integrate clinical, dermoscopic, and histologic findings in the diagnosis of acral lentiginous melanoma. In addition, molecular studies can be helpful. In this review, we have summarized our current understanding of this disease entity from articles that were published between 1969 and 2018. We have outlined clinical and dermoscopic features as well as pathologic and molecular findings regarding acral melanoma and have presented an algorithm for diagnosis. Understanding and integrating these characteristics may assist clinicians in the early detection of acral melanomas.

Improving the diagnosis and treatment of acral melanocytic lesions

Melanocytic lesions of acral sites are common, with an estimated prevalence of 28-36% in the USA. While the majority of these lesions are benign, differentiation from acral melanoma (AM) is often challenging. AM is a unique subtype of melanoma, with distinct molecular characteristics that are thought to contribute to its high rate of locoregional recurrence and worse prognosis. The advent of dermoscopy has since improved the diagnostic accuracy of AM, resulting in earlier detection and arguably improved survival. Additionally, the identification of unique genomic amplifications in AM invites the potential for future AM-specific targeted therapies. Herein, we discuss the importance of dermoscopy in the diagnosis of acral melanocytic lesions and review the treatment strategies for AM.

Dermoscopic Findings of an Unusual Acral Nevus on the Hand of a Child

Distinguishing benign acral nevi from small early acral melanomas may be challenging in certain cases. Dermoscopy is a noninvasive imaging technique that can help clinicians better visualize deeper lesion structures and thus more easily differentiate benign nevi from melanoma. We report the case of a 13-year-old girl with a changing dark brown to black macule with a central papular component on the volar surface of the right third finger. Dermoscopy revealed asymmetrically distributed irregular black blotches on a bluish-black background. Histopathology revealed a traumatized compound melanocytic nevus. Certain melanocytic nevi, although histologically benign, may not conform to the limited selection of reassuring benign dermoscopic patterns. Nevi in children are often dynamic and have a high likelihood of dermoscopic change.

Atypical dermoscopic presentation of an acral congenital melanocytic nevus in an adult: parallel ridge pattern and its histologic correlation

Acral melanoma is the most frequent subtype in the Asian and Mexican mestizo populations. Dermoscopy is a noninvasive diagnostic technique that helps the differential diagnosis of pigmented skin lesions on acral volar skin.

We, herein, present a case of acral congenital melanocytic nevus with a parallel ridge dermoscopic pattern. Since the parallel ridge pattern in a melanocytic lesion of the acral skin is classically ascribed to melanoma, the present case can be definitely labeled as “atypical” and worth of being elucidated in its histopathological correlates.

Update on melanocytic nevi in children

A new or changing melanocytic nevus in a child or adolescent often leads to concern in parents and physicians. To avoid undue alarm and unnecessary procedures, dermatologists should be aware of the natural history and clinical spectrum of nevi in pediatric patients, as well as findings that are potentially worrisome in this age group. This review provides an update on melanocytic nevi in children, focusing on their dynamic evolution over time, molecular insights into nevogenesis, and phenotypic markers for increased risk of melanoma in adolescence and adulthood. Special considerations for Spitz nevi and nevi located in particular sites (eg, scalp, acral, genital) are highlighted. Current understanding of the risks associated with congenital melanocytic nevi of different sizes and strategies for the management of children with numerous acquired nevi, Spitz nevi, and congenital nevi are also discussed.