A Phan1, S Dalle, S Touzet, S Ronger-Savlé, B Balme, L Thomas. 1. Department of Dermatology, Centre Hospitalier Lyon-Sud, Claude Bernard University, 165 chemin du Grand-Revoyet, 69495 Pierre Bénite, France.
Abstract
BACKGROUND: Acral lentiginous melanoma (ALM) is a rare but distinctive subtype of melanoma. The diagnosis is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation and a higher rate of amelanosis than in other melanoma subtypes. OBJECTIVES: We aimed to investigate the dermoscopic features of a large series of ALM in a white-skinned population, in order to emphasize their diagnostic value. METHODS: All recorded dermoscopic photographs of ALM, including nail unit variants, were collected from the files of the University Hospital Department of Dermatology (Lyons, France) and reviewed. RESULTS: In total 110 lesions, including 66 (60%) palmoplantar ALM and 44 (40%) ALM of the nail apparatus, were analysed for dermoscopic characteristics. The mean Breslow thickness was 2.6 mm. In volar skin melanomas, the two most prevalent patterns were irregular diffuse pigmentation (60%) and the parallel-ridge pattern (53%). Minor dermoscopic patterns, commonly noted in benign lesions, were also detected but only focally within the lesions. Among the 44 nail unit lesions, 31 (70%) presented irregular lines with variegations in colours, spacing, width and disruption of parallelism. Two cases of melanonychia striata had a triangular shape. Both corresponded to early ungual ALM. Association with subungual haemorrhage was not uncommon. The study included 37 (34%) amelanotic melanomas. However, dermoscopy enabled detection of microscopic remnants of pigmentation in most cases. The vascular pattern found in almost half of these lesions was polymorphous, with combinations of milky-red areas (95%), linear irregular vessels (49%), dotted vessels (43%) and hairpin vessels (41%). CONCLUSIONS: The presence of a parallel-ridge pattern and/or irregular diffuse pigmentation within the lesion is highly indicative of melanoma on volar skin. An irregular lines pattern is the most prominent dermoscopic feature of pigmented ALM of the nail apparatus. Amelanotic ALM either in volar skin or in nail apparatus is characterized by remnants of pigmentation and a polymorphic vascular pattern.
BACKGROUND:Acral lentiginous melanoma (ALM) is a rare but distinctive subtype of melanoma. The diagnosis is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation and a higher rate of amelanosis than in other melanoma subtypes. OBJECTIVES: We aimed to investigate the dermoscopic features of a large series of ALM in a white-skinned population, in order to emphasize their diagnostic value. METHODS: All recorded dermoscopic photographs of ALM, including nail unit variants, were collected from the files of the University Hospital Department of Dermatology (Lyons, France) and reviewed. RESULTS: In total 110 lesions, including 66 (60%) palmoplantar ALM and 44 (40%) ALM of the nail apparatus, were analysed for dermoscopic characteristics. The mean Breslow thickness was 2.6 mm. In volar skin melanomas, the two most prevalent patterns were irregular diffuse pigmentation (60%) and the parallel-ridge pattern (53%). Minor dermoscopic patterns, commonly noted in benign lesions, were also detected but only focally within the lesions. Among the 44 nail unit lesions, 31 (70%) presented irregular lines with variegations in colours, spacing, width and disruption of parallelism. Two cases of melanonychia striata had a triangular shape. Both corresponded to early ungual ALM. Association with subungual haemorrhage was not uncommon. The study included 37 (34%) amelanotic melanomas. However, dermoscopy enabled detection of microscopic remnants of pigmentation in most cases. The vascular pattern found in almost half of these lesions was polymorphous, with combinations of milky-red areas (95%), linear irregular vessels (49%), dotted vessels (43%) and hairpin vessels (41%). CONCLUSIONS: The presence of a parallel-ridge pattern and/or irregular diffuse pigmentation within the lesion is highly indicative of melanoma on volar skin. An irregular lines pattern is the most prominent dermoscopic feature of pigmented ALM of the nail apparatus. Amelanotic ALM either in volar skin or in nail apparatus is characterized by remnants of pigmentation and a polymorphic vascular pattern.
Authors: C M Costello; S Ghanavatian; M Temkit; M R Buras; D J DiCaudo; D L Swanson; A R Mangold Journal: J Eur Acad Dermatol Venereol Date: 2017-12-18 Impact factor: 6.166
Authors: Ivan R Bristow; David Ar de Berker; Katharine M Acland; Richard J Turner; Jonathan Bowling Journal: J Foot Ankle Res Date: 2010-11-01 Impact factor: 2.303
Authors: Jacqueline Dinnes; Jonathan J Deeks; Naomi Chuchu; Rubeta N Matin; Kai Yuen Wong; Roger Benjamin Aldridge; Alana Durack; Abha Gulati; Sue Ann Chan; Louise Johnston; Susan E Bayliss; Jo Leonardi-Bee; Yemisi Takwoingi; Clare Davenport; Colette O'Sullivan; Hamid Tehrani; Hywel C Williams Journal: Cochrane Database Syst Rev Date: 2018-12-04