Nuchal-type fibroma is a rare benign proliferation involving the dermis and subcutaneous tissues, that is a collection of dense, hypocellular bundles of collagen with entrapped adipocytes and increased numbers of small nerves. It is no longer called a nuchal fibroma, but instead a "nuchal-type fibroma" since it develops in other anatomic sites. There is no known etiology.[1][2] The World Health Organization in 2020 classified nuchal fibromas as a specific tumor form in the category of benign fibroblastic and myofibroblastic tumors.[3]
^Samadi, D. S.; McLaughlin, R. B.; Loevner, L. A.; Livolsi, V. A.; Goldberg, A. N. (2000). "Nuchal fibroma: A clinicopathological review". The Annals of Otology, Rhinology, and Laryngology. 109 (1): 52–55. doi:10.1177/000348940010900110. PMID10651413.