Fibroma Abnormal periungual morphology Ungual fibroma 2011-06-09T11:59:55Z Koenen's tumour Ungual fibromas are characteristic of tuberous sclerosis. Koenen's tumor Koenen tumour Koenen tumor Parungual fibromas UMLS:C0442880 Periungual fibroma Flesh-colored papule in or around the nail bed. Ungual fibromas may be periungual (arising under the proximal nail fold) or subungual (originating under the nail plate). SNOMEDCT_US:264561009 HP:0100804 Neoplasm of the nail