Can we manage the melanocytic lesions with peripheral globules according to the grade of dysplasia?

BACKGROUND/

OBJECTIVES

Although excision of melanocytic nevi with high-grade dysplasia is recommended by the World Health Organization (WHO), clinical studies investigating the approach based on the grading dysplasia of melanocytic lesions with peripheral globules (PGs) are lacking. We investigated the grades of dysplasia and their distinguishable dermoscopic and clinical features to provide accurate data for managing these lesions.

METHODS

We retrospectively classified histologically confirmed melanocytic lesions with PGs according to the 2018 WHO Classification of Skin Tumours criteria in a university hospital in Turkey. Dermoscopic features, lesions, and patient characteristics were recorded.

RESULTS

Sixty-six lesions of 56 patients were included. After classification, 9.1% (n: 6) of lesions were melanomas, 39.4% (n: 26) were high-grade dysplastic nevi, and 50% (n: 33) were low-grade dysplastic nevi (n: 33, 50%). There was one nevus with no dysplasia (n: 1, 1.5%). Univariate analysis revealed that ≥31 years of age, irregular shape of peripheral globules, black colour, total colour count, and maximum diameter of the lesion were associated with high-grade dysplasia and melanoma. In the multivariate analyses, ≥31 years of age (OR = 3.80, 95% CI, 1.17-12.37), irregular shape of peripheral globules (OR = 3.90, 95% CI, 1.15-13.2), and total colour count (OR = 3.21, 95% CI, 1.2-8.5) were significant predictive factors for the lesions with high-grade dysplasia and melanomas.

CONCLUSIONS

To avoid the underdiagnosis of both melanomas and high-grade dysplastic nevi with PGs, the irregular shape of peripheral globules and multiple colours after the third decade may be useful in making an excision decision. The risk increases every 1-year increase in age. Excision is suggested for all melanocytic lesions with PGs for patients 60 years or older because of the high risk of melanoma and melanocytic nevus with high-grade dysplasia.