Risk of Malignant Transformation of Congenital Melanocytic Nevi: A Retrospective Nationwide Study from the Netherlands

Abstract

Our study shows that congenital melanocytic nevi have a significantly higher risk of developing a malignant melanoma compared with the age-, sex-, calendar-period-specific reference data from The Netherlands Cancer Registry.

Congenital melanocytic nevi: Where are we now?

“…101,102 However, most studies show an incidence rate of melanoma in small and medium CMN of\1%. 3,5,19,[103][104][105][106][107] This compares with a general lifetime risk of MM in the United States of 1.97%. 108 Concerning medium-sized CMN, a prospective study of 230 (1.5-19.9 cm) CMN with an average follow-up of 6.7 years to an average age of 25.5 years found that no MM developed in any of the lesions.…”

Malignant Transformation of a Multi-Operated Divided Nevus of the Eyelids

“…Only congenital melanocytic nevi larger than 20 cm in diameter (called “giant nevi”) have a particularly high malignant risk; divided nevi are generally small to medium-sized and are thus at low risk [11]. To our knowledge, 2 cases of melanoma arising on a preexisting divided nevus have been reported to date.…”

Giant congenital melanocytic nevus - Reconstruction using multiple modalities: A case report

“…This has been modified to define large lesions as those that are 11 cm to 20 cm in diameter, and naevi larger than 20 cm are considered as giant lesions [4] . As there is a risk of malignant degeneration associated with large and giant CMN (reported to reach up to 12 percent) [5,6] , it is common practice to completely excise such lesions. It is also thought that surgical excision may reduce the risk of malignant degeneration.…”