Neurofibroma (NF)

• Common benign growth; multiple NFs or plexiform NF associated with neurofibromatosis
• Presents typically as solitary, slow-growing skin-colored to pink papule with soft or rubbery feel, ± pedunculated, + “buttonhole sign” (invagination with compression by finger)
• Histology: typically unencapsulated somewhat demarcated nodular proliferation in dermis consisting of spindle cells with wavy nuclei, pale “bubble gum” stroma or fibromyxoid stroma, and mast cells