plexiform neurofibroma

Plexiform Neurofibroma Description

A plexiform neurofibroma is a type of benign peripheral nerve sheath tumor that arises from Schwann cells, generally surrounding multiple nerve fascicles [2]. It is characterized by its growth pattern, consisting of multiple tortuous cords and nodules of variable size that correspond to nerve fascicles replaced and expanded by neurofibromatous tissue [4].

This type of tumor is often larger and more diffuse than cutaneous neurofibromas, with less well-defined borders [5]. Plexiform neurofibromas can involve multiple nerve fascicles and are typically associated with neurofibromatosis type 1 (NF1), also known as von Recklinghausen's disease [1].

The lesions most often present in children who have NF1, and symptoms may include paralysis, weakness or numbness from pressure on their spinal cord [14]. A plexiform neurofibroma is essentially diagnostic of NF1, affecting 20% to 40% of patients with this syndrome [4].

In terms of microscopic description, plexiform neurofibromas are characterized by multinodular, plexiform or tortuous bundles of bland spindle cells consistent with expanded nerve branches [2]. This type of tumor is often irregular, thick and non-circumscribed, involving multiple nerve fascicles [7].

Overall, a plexiform neurofibroma is a complex and multifaceted condition that requires careful diagnosis and management.

References:

[1] People who get plexiform neurofibromas are usually born with a rare genetic disease called neurofibromatosis type 1 (NF1), or von Recklinghausen’s disease. Around 30% to 50% of people who have ...

[2] Microscopic (histologic) description. Multinodular, plexiform or tortuous bundles of bland spindle cells consistent with expanded nerve branches ... Plexiform neurofibroma is a benign peripheral nerve sheath tumor that arises from Schwann cells, generally surrounding multiple nerve fascicles

[4] Plexiform neurofibroma is essentially diagnostic of NF1, affecting 20% to 40% of patients with this syndrome. 228,229 It is defined by its growth pattern, consisting of multiple tortuous cords and nodules of variable size that correspond to nerve fascicles replaced and expanded by neurofibromatous tissue.

[5] Unlike cutaneous neurofibromas that typically grow as small nodules, plexiform neurofibromas are often larger, diffuse growths with less well-defined borders. ...

[7] by P Poswal · 2020 · Cited by 19 — Plexiform neurofibroma is an irregular, thick and non circumscribed tumor of peripheral nerve sheath which can involve multiple nerve fascicles.

[14] Plexiform neurofibromas:This type of neurofibroma grows on groups of nerves. Plexiform neurofibromas often affect children who have neurofibromatosis Type 1. These tumors can grow over time, becoming very large lumps on children’s skin or under their skin. Symptoms may include paralysis, weakness or numbness from pressure on their spinal cord ...

Plexiform neurofibromas can be challenging to diagnose, but various diagnostic tests are available to help confirm their presence and extent.

• Imaging scans: Magnetic Resonance Imaging (MRI) is a commonly used imaging modality for evaluating internal lesions such as mediastinal masses, spinal cord tumors, deep plexiform neurofibromas, and neurofibromas in the brain [5]. MRI has proven useful in evaluating the full extent of the lesion, which is best seen by this type of scan [8].
• Computerized Tomography (CT) scans: CT scans can also be used to evaluate internal lesions and may be used in conjunction with MRI for a more comprehensive assessment.
• Electromyography (EMG): EMG is a study that measures the electrical activity of muscles. It can help diagnose nerve damage or dysfunction, which may be associated with plexiform neurofibromas [7].
• Biopsies: In some cases, a biopsy may be necessary to confirm the diagnosis of a plexiform neurofibroma. However, this is typically reserved for situations where imaging studies are inconclusive.
• Genetic testing: Genetic tests can also be done in pregnancy before a baby is born to see whether a mutation in the neurofibromatosis type 1 gene is present [3]. This can help support the diagnosis of NF1 and plexiform neurofibromas.

It's worth noting that diagnostic tests for plexiform neurofibromas may include regular checkups and imaging tests to see if the tumor is growing, as well as medicine to treat a plexiform neurofibroma [11]. Selumetinib (Koselugo) has been approved to treat a plexiform neurofibroma in children with neurofibromatosis type 1.