The extent of Hutchinson’s nail sign (HS) may be a useful prognostic indicator in patients with subungual melanoma, according to study data published in the Journal of the European Academy of Dermatology and Venereology.
This retrospective cohort study enrolled consecutive patients with subungual melanoma who received care at a treatment center in South Korea from 2006 through 2017. The extent of HS was determined by the number of affected nail folds (0-4). Three pairwise comparisons were conducted: 1) patients with HS (affecting ≥1 nail folds) vs without HS; 2) patients with HS affecting ≥2 nail folds vs HS affecting <2 nail folds; and 3) patients with HS affecting ≥3 nail folds vs HS affecting <3 nail folds. Clinical features and treatment outcomes were compared in the groups.
A total of 61 patients with subungual melanoma were enrolled, of whom 46 (75.4%) exhibited HS. Mean age at subungual melanoma diagnosis was 66.38 ± 13.25 years; 33 patients (54.1%) were women. Nail destruction (87.0% vs 40.0%; P <.001) and ulceration (45.7% vs 13.3%; P <.026) were more common in patients with HS than in patients without HS. The majority (91.7%) of patients with HS underwent surgical excision of the primary lesions, for which amputation (73.9%) was the most common method. In multivariate analyses, patients with HS affecting ≥2 nail folds were significantly more likely to undergo amputation than patients with <2 folds affected (hazard ratio [HR], 4.75; 95% confidence interval [CI], 1.36–16.61; P =.015). Patients with nail destruction had a 10-fold increased risk for HS appearing in ≥1 nail fold (HR, 10.00; 95% CI, 2.61-38.30; P =.001). In addition, patients with HS appearing in ≥3 nail folds had higher T scores than patients with HS affecting <3 folds (HR, 4.75; 95% CI, 1.36–16.61; P = 0.015).
As study limitations, investigators cited the retrospective design and short follow-up period.
The extent of HS appeared to predict certain clinical features of subungual melanoma, including likelihood of amputation and T stage. Further study in a prospective cohort is necessary to assess survival rates in patients with and without HS. However, “[t]he number of affected nail folds could be a useful clinical clue for planning therapeutic strategies for [subungual melanoma],” investigators wrote.
Sohng C, Han MH, Park D, et al. Clinical features of subungual melanoma according to the extent of Hutchinson’s nail sign: a retrospective single-centre study [published online June 20, 2020]. J Eur Acad Dermatol Venereol. doi: 10.1111/jdv.16762