Thelansis

  Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are aggressive soft tissue tumors primarily originating from the peripheral nerves. They demonstrate variable differentiation towards the cellular components of the nerve sheath, such as Schwann cells, fibroblasts, or perineurial cells. MPNSTs are common in adults with no gender bias but tend to occur at a younger mean age in patients with neurofibromatosis type 1 (NF1). The tumors are most frequently found in the extremities, particularly proximally, followed by the trunk, head, and neck. The sciatic nerve is the most commonly involved nerve trunk. Clinical presentation includes a painful or rapidly growing mass and associated neurologic deficits. Approximately half of the MPNSTs arise in the context of NF1 syndrome, often associated with pre-existing plexiform neurofibromas. The lifetime risk of developing MPNST in NF1 patients is 8-13%. An important symptom is developing new, worsening, or persistent pain in a neurofibroma in an