Plexiform neurofibromas are a specific type of neurofibroma, which are benign tumors that arise from the peripheral nerve sheath. These tumors are often associated with Neurofibromatosis Type 1 (NF1), a genetic disorder caused by mutations in the NF1 gene. Plexiform neurofibromas are characterized by their complex, multi-nodular growth pattern, which infiltrates along nerves and can involve multiple fascicles. This makes them distinct from other forms of neurofibromas.