Patients with non-supernumerary ring chromosome 7 syndrome have an increased incidence of hemangiomas, café-au-lait spots, and melanocytic nevi. The mechanism for the increased incidence of these benign neoplasms is unknown. We present the case of a 22-year-old man with ring chromosome 7 and multiple melanocytic nevi. Two nevi, one on the right ear and the other on the right knee, were biopsied and diagnosed as desmoplastic Spitz nevi. Upon targeted next-generation DNA sequencing, both harbored BRAF fusions. Copy number alterations and fluorescence in situ hybridization (FISH) for BRAF suggested that the fusions arose on the ring chromosome 7. Hence, one reason for increased numbers of nevi in patients with non-supernumerary ring chromosome 7 syndrome may be increased likelihood of BRAF fusions, due to the instability of the ring chromosome.
Bibliographical noteFunding Information:
This work was supported by the National Cancer Institute at the National Institutes of Health (grant number 1R35CA220481).
© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
- BRAF fusion
- BRAF gene
- melanocytic nevi
- melanocytic nevus
- ring chromosome 7
- ring chromosome seven
- Spitz nevus
- Spitz tumor
PubMed: MeSH publication types
- Case Reports
- Research Support, N.I.H., Extramural