UNASSIGNED: @entity10401 , which are benign smooth @entity11090 , commonly present as dermal-based nodules or papules with smooth borders and firm consistency. Digital, particularly subungual @entity10401 are quite rare. A 16-year-old female presented to nail clinic complaining of discoloration of the lunula of the left thumbnail for 2.5   months. On initial examination, a pink longitudinal band was present in the center of the nail plate, with yellow discoloration and distal onycholysis. The @entity1 had only mild tenderness with firm palpation, and did not recall trauma of the area. A nail matrix biopsy was performed to determine the etiology of the lesion. Microscopic examination demonstrated a well-demarcated dermal-based spindle-cell fascicular proliferation. Bland cells exhibited eosinophilic cytoplasm and elongate nuclei with blunt ends and minimal cytologic atypia. Prominent nucleoli, mitoses or @entity39 were not appreciated. Immunohistochemical stains for smooth muscle actin and caldesmon highlighted the cells. Contrarily, @entity4483 , epithelial membrane antigen, @entity4206 , @entity21939 , @entity2280 , @entity469 and @entity2251 were all negative. Ki-67 showed a low proliferative index. The immunoprofile combined with the morphologic features were interpreted as @entity2909 . @entity2909 is a very rare diagnosis. We seek to bring awareness and expedite the diagnosis in @entity1 with this lesion.

XXXX in the left thumb of a 16-year-old female.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity39 :: ('MESH:D009336', 'Disease') :: ['necrosis'] @entity4206 :: ('8626', 'Gene') :: ['p63'] @entity469 :: ('968', 'Gene') :: ['CD68'] @entity4483 :: ('6285', 'Gene') :: ['S-100'] @entity2251 :: ('11168', 'Gene') :: ['p75'] @entity10401 :: ('MESH:C535516', 'Disease') :: ['Cutaneous leiomyomata', 'leiomyomata'] @entity11090 :: ('MESH:D019042', 'Disease') :: ['muscle neoplasms'] @entity2280 :: ('947', 'Gene') :: ['CD34'] @entity21939 :: ('2162', 'Gene') :: ['factor XIIIa'] @entity2909 :: ('MESH:D007889', 'Disease') :: ['Subungual leiomyoma', 'subungual leiomyoma']
@entity2909 :: (MESH:D007889,Disease) :: ['Subungual leiomyoma']
