Congenital nevus
Nail unit melanoma in children is extremely rare and very difficult to diagnose [1]. Moreover, unfortunately, clinical as well as dermoscopic criteria used in adults cannot be applied to children since congenital nevi of the nail unit are characterized by signs that are considered extremely suspicious of melanoma in adults[2][3][4][5][6].
Triangular shape of the band, irregularity of its pigmentation, nail plate softening or erosion, and periungual pigmentation are very common features of congenital (or congenital-type) nevi of the nail unit. For these reasons, the International Society for Dermoscopy (IDS) has created an international register of congenital and congenital-type nevi of the nail unit. To date, this register has included more than 150 cases worldwide of pigmented lesions of the nail unit either present at birth or diagnosed during the first 5 years of life. This ethical committee-approved register is located in Lyons, France, and held by Lyon 1 Claude Bernard University Dermatology Department. Details for submission of cases can be found on the IDS website[7][8].
Since this observational study is still ongoing, we will only include here, with few illustrations, some of our preliminary findings. We commonly determined that an irregular pattern of the dermoscopic longitudinal microlines as well as a triangular shape of the whole band were present in early observations. Periungual involvement, also known as Hutchinson’s sign, was also a very common finding, with a remarkable tropism for the toe/fingertip. The pigmentation in the skin distal to the hyponychium often had a longitudinal and parallel disposition perpendicular to the dermatoglyphics. In rare cases with extremely wide involvement of the periungual skin, a disposition of the pigment along the furrows of the dermatoglyphics, reproducing the classic parallel furrow pattern[9] of benign acral nevi, was observed. We also noticed that a more regular pattern of the pigmentation appeared after a few years of evolution and that, in some cases, the pigmentation faded away almost completely.
Inclusion of new cases in the register[10] is greatly needed and encouraged in order to increase our knowledge of the natural history of congenital nevi of the nail matrix and to better codify the management of these very difficult cases.
- ↑ Altamura D, Avramidis M, Menzies SW. (2008) Assessment of the optimal interval for and sensitivity of short-term sequential digital dermoscopy monitoring for the diagnosis of melanoma. Arch Dermatol 144(4): 502–6.
- ↑ Iorizzo M, Tosti A, Di Chiacchio N et al. (2008) Nail melanoma in children: differential diagnosis and management. Dermatol Surg 34(7): 974–8.
- ↑ Richert B, André J. (2011) Nail disorders in children: diagnosis and management. Am J Clin Dermatol 12(2): 101–12.
- ↑ Léauté-Labrèze C, Bioulac-Sage P, Taïeb A. (1996) Longitudinal melanonychia in children. A study of eight cases. Arch Dermatol 132(2): 167–9. Erratum in: Arch Dermatol 132(9): 112.
- ↑ Wong DE, Brodkin RH, Rickert RR, McFalls SG. (1991) Congenital melanonychia. Int J Dermatol 30(4): 278–80
- ↑ Coskey RJ, Magnell TD, Bernacki EG Jr. (1983) Congenital subungual nevus. J Am Acad Dermatol 9(5): 747–51.
- ↑ Caron GA. (1962) Familial congenital pigmented naevi of the nails. Lancet 1(7228): 508–9.
- ↑ www.dermoscopy–ids.org/
- ↑ www.dermoscopy–ids.org/index.php/studies
- ↑ Caron GA. (1962) Familial congenital pigmented naevi of the nails. Lancet 1(7228): 508–9.
