Diagnosis and Management of Acral Pigmented Lesions

Abstract

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.

A European Multicentric Investigation of Atypical Melanocytic Skin Lesions of Palms and Soles: The iDScore-PalmoPlantar Database

“…According to patient data analysis, age turned out to be a significant discriminant factor for malignancy ( Table 4 , p < 0.001), with patients with PP melanoma generally being older (65.3 years on average) than those with benign aMPPLs (41.33 yrs on average). These data are globally in line with those reported in acral melanoma patients diagnosed in Asia [ 12 ], France [ 3 ], United States [ 26 ], Spain [ 46 ], Italy [ 9 ], and Korea [ 47 ], aged between 59 and 65 years, and those reported from acral nevi patients diagnosed in the United States [ 4 ], Italy [ 26 ], and Greece [ 25 ].…”

“…Dermoscopic examination was shown to help increase the diagnostic accuracy of MPPLs, especially in differentiating malignant from benign cases [ 21 , 22 ] and in clear-cut lesions. Indeed, considering clear-cut PP nevi and PP melanomas, a series of specific dermoscopic patterns were first described by Japanese study groups and included benign-related features (parallel furrow pattern, lattice-like, fibrillar, globular, and homogenous) and malignancy-related features (parallel-ridge pattern, irregular diffuse pigmentation, and multicomponent pattern) [ 7 , 9 , 11 , 23 , 24 , 25 ]. We have otherwise to keep in mind that there are atypical MPPLs (aMPPLs) that exhibit equivocal clinical and dermoscopic features, including PP nevi mimicking PP melanomas (e.g., asymmetrical, maculopapular, and with non-homogenous pigmentation) and, vice versa, featureless or doubtful early melanoma [ 1 , 10 , 13 , 26 ].…”

“…We have otherwise to keep in mind that there are atypical MPPLs (aMPPLs) that exhibit equivocal clinical and dermoscopic features, including PP nevi mimicking PP melanomas (e.g., asymmetrical, maculopapular, and with non-homogenous pigmentation) and, vice versa, featureless or doubtful early melanoma [ 1 , 10 , 13 , 26 ]. In this subset of difficult “borderline” lesions, dermoscopy alone cannot reach adequate diagnostic accuracy, and further parameters should be taken into account to assess the risk of that lesion being malignant [ 24 , 25 , 26 ]. It has been widely demonstrated that the Bayesian scoring classifier models are reliable tools able to efficiently select and combine a series of patient and lesion objective parameters with dermoscopic data, with the final aim of developing a risk scoring model dedicated to a specific subset of lesions [ 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

Pattern Analysis of Benign and Malignant Atypical Melanocytic Skin Lesions of Palms and Soles: Variations of Dermoscopic Features According to Anatomic Site and Personal Experience

“…AM differs from the other melanoma forms in the biological profile causing specific genetic/immunohistochemical features and related behaviors [ 8 , 9 , 10 , 11 , 12 ]: first, it is a non-UV-related tumor arising from the epithelium-associated melanocytes; second, it shows the early onset of major chromosomal rearrangements with gene copy number changes and multiple high-level amplifications (e.g., driver mutations in GNAQ, NF1, KIT TP53, PTEN, or RB1 genes, versus BRAF and NRAS of superficial spreading and nodular melanoma) [ 13 ]; third, it exhibits specific molecular findings (e.g., CCND1 overexpression , AURKA , and TERT) [ 14 ]; fourth, it is characterized by a rapid evolution and ability to metastasize and, thus, a poor prognosis [ 15 , 16 , 17 ]. This said, AM is also known for having a late diagnosis compared with other forms: the more reported underlying hypothesis emphasize the patients’ (and/or physicians’) reticence in examining this area and the difficulty of the differential diagnosis with acral nevi -with reported rates of misdiagnosis of 20%—despite dermoscopic examination [ 18 , 19 , 20 , 21 ]. Dermoscopy is nowadays the most common technique for non-invasive imaging in dermatology, able to provide a “radiography” of pigmented skin lesions through a polarized light source that reaches the dermal–epidermal junction [ 22 ].…”

Plantar Hyperpigmentation

“…The mortality rate for acral melanoma in Black patients is disproportionately high for the following reasons 15,16 :…”