Acral lentiginous melanoma in situ: dermoscopic features and management strategy

Abstract

Diagnosis of acral lentiginous melanoma in situ (ALMIS) is challenging. However, data regarding ALMIS are limited in the literature. The aim of this study was to investigate the clinical and dermoscopic features of ALMIS on palmoplantar surfaces. Patients with ALMIS and available dermoscopic images were retrospectively reviewed at our institution between January 2013 and February 2020. Clinical and dermoscopic features were analysed and compared between small (< 15 mm) and large (≥ 15 mm) ALMIS. Twenty-one patients with ALMIS were included in this study. Mean patient age was 58.5 (range 39–76) years; most lesions were located on the sole (90.5%). The mean maximal diameter was 19.9 ± 13.7 mm (mean ± standard deviation). Statistical analysis of dermoscopic features revealed that parallel ridge patterns (54.5% vs. 100%, P = 0.035), irregular diffuse pigmentation (27.3% vs. 100%, P = 0.001) and grey colour (18.2% vs. 90%, P = 0.002) were significantly less frequent in small lesions than in large lesions. We have also illustrated two unique cases of small ALMIS; their evolution and follow-up dermoscopic examination are provided. In conclusion, this study described detailed dermoscopic findings of ALMIS. Based on the present study and a review of the literature, we proposed a dermoscopic algorithm for the diagnosis of ALMIS.

Nomogram for Predicting Overall Survival in Acral Lentiginous Melanoma: A Population‐based Study

“…ALM is the main type of melanoma in colored races. 31 Studies have found that ALM occurs less frequently in white people, accounting for only 4%–10% of skin melanoma, but it has a higher proportion in Hispanic, Asian, African, and other people of color. 32–35 Of note, the study also found that being unmarried and DSW were risk factors affecting the prognosis of patients with ALM.…”

Diagnosis and Management of Acral Pigmented Lesions

“…26 The parallel ridge pattern (PRP) has been described as the most characteristic pattern of ALM, although its absence does not exclude a possible diagnosis of ALM. 27,28 Parallel ridge pattern presents as pigment along the ridges. 29 The sensitivity and specificity of PRP in ALM are 86.4% and 99%, respectively.…”

“…30 By contrast, benign lesions display benign patterns throughout the lesion. Advanced ALM may also show non-site-specific dermoscopic features of melanoma, such as irregular dots and globules, irregular streaks and pseudopods, regression structures, blue-white veil, and atypical vessels 27,28 (see Supplemental Digital Content 1, Table 3, http://links.lww.com/DSS/B301).…”

Dermoscopy for acral melanocytic lesions: Revision of the 3-step algorithm and refined definition of the regular and irregular fibrillar pattern

“…Based on these characteristic dermoscopic findings, in 2007 our group proposed a dermoscopic 3-step algorithm for the management of acral melanocytic lesions [3] and then, revised it in 2011 [4]. Recently, several studies were reported which examined utility of the 3-step algorithm [5][6][7]. In these studies, the 3-step algorithm generally worked well, however, in one study, the algorithm missed one lesion of AM, 0.5 mm in Breslow thickness.…”