What is the Difference Between Neurofibroma and Neurofibromatosis

The key difference between neurofibroma and neurofibromatosis is that neurofibroma is a condition where benign, slow-growing nerve-sheath tumors grow in the peripheral nervous system, while neurofibromatosis is a group of three conditions in which benign tumors grow in supporting cells and neurons of the nervous system.

Nervous system tumors typically develop in the brain and spinal cord. They can be either benign (non-cancerous) or malignant (cancerous). The tumors that originally grow in the nervous system are primary tumors, while tumors that begin elsewhere in the body and spread to the nervous system are secondary tumors (metastatic). These tumors may affect both the central and peripheral nervous systems. Neurofibroma and neurofibromatosis are two types of conditions where benign tumors grow in the nervous system.

CONTENTS

1. Overview and Key Difference
2. What is Neurofibroma
3. What is Neurofibromatosis
4. Similarities – Neurofibroma and Neurofibromatosis
5. Neurofibroma vs Neurofibromatosis in Tabular Form
6. Summary – Neurofibroma vs Neurofibromatosis

What is Neurofibroma?

Neurofibroma is a condition where benign, slow-growing nerve-sheath tumors grow in the peripheral nervous system. In 90% of cases, it is a stand-alone or solitary tumor condition. In the remaining cases, it is found in persons with neurofibromatosis type I. A neurofibroma can develop within a major or minor or nerve anywhere in the body. The symptoms are often mild or absent. However, if the tumors press against nerves or grow within them, people may experience pain or numbness in the affected area. The cause of sporadic neurofibroma is not known. But other neurofibromas arise from non-myelinated Schwann cells that only express the inactive version of the NF1 gene. This leads to a complete loss of expression of functional neurofibromin.

Figure 01: Neurofibroma

This condition has been subdivided into two categories: dermal and plexiform. Dermal neurofibromas are associated with a single peripheral nerve, while plexiform neurofibromas are associated with multiple nerve bundles. Dermal neurofibroma further divides into; cutaneous, subcutaneous, and deep nodular. The diagnosis can be made through blood tests, biopsy, MRI or electromyography (EMG/NCV). Treatments include surgery, radiation, chemotherapy, ACE inhibitors, MEK inhibitors, and drugs such as sirolimus, erlotinib, peginterferon alfa-2b, sorafenib, etc. Gene therapy for neurofibromin I gene may be a treatment option in the future.

What is Neurofibromatosis?

Neurofibromatosis is a group of three conditions (neurofibromatosis I, neurofibromatosis II, and schwannomatosis) in which benign tumors grow in supporting cells and neurons of the nervous system. In neurofibromatosis I, the symptoms include light brown spots on the skin, freckles in the armpit and groin, bumps in nerves and scoliosis. In neurofibromatosis II, symptoms include hearing loss, cataracts at a young age, balance problems, flesh coloured skin flaps, and muscle wasting. Furthermore, in schwannomatosis, there may be pain either in one location or in wide areas of the body. Neurofibromatosis usually arises from supporting cells of the nervous system rather than the neurons themselves.

Figure 02: Neurofibromatosis

Neurofibromatosis is caused by genetic mutations in certain genes that can be inherited or spontaneously occurring. Neurofibromatosis I is caused due by mutation of the NF1 gene on chromosome 17. Neurofibromatosis II is caused due by mutation of the NF2 gene on chromosome 22. Schwannomatosis is due to various mutations on chromosome 22. The diagnosis is through medical imaging, biopsy, and genetic testing. The treatment plan includes surgery, radiation, chemotherapy, cochlear implant, or auditory brainstem implant for people who have hearing loss due to this condition.

What are the Similarities Between Neurofibroma and Neurofibromatosis?

• Neurofibroma and neurofibromatosis are two types of conditions where benign tumors grow in the nervous system.
• Both conditions are slow-growing.
• These conditions are generally non-cancerous.
• They can be due to genetic mutation of the NF1 gene.
• They are treatable with removal surgery, radiation and chemotherapy.

What is the Difference Between Neurofibroma and Neurofibromatosis?

Neurofibroma is a condition where benign slow-growing nerve-sheath tumors grow in the peripheral nervous system, while neurofibromatosis is a group of three conditions, neurofibromatosis I, neurofibromatosis II, and schwannomatosis, in which benign tumors grow in supporting cells and neurons of the nervous system. So, this is the key difference between neurofibroma and neurofibromatosis. Furthermore, neurofibroma affects only the peripheral nervous system, while neurofibromatosis affects both peripheral and central nervous systems.

The following table summarizes the difference between neurofibroma and neurofibromatosis.

Summary – Neurofibroma vs Neurofibromatosis

Nervous system tumors usually affect both peripheral and central nervous systems. Neurofibroma and neurofibromatosis are two types of conditions where benign tumors grow in the nervous system. Neurofibroma is a condition where benign slow-growing nerve-sheath tumors grow in the peripheral nervous system, while neurofibromatosis is a group of three conditions (neurofibromatosis I, neurofibromatosis II, and schwannomatosis) in which benign tumors grow in supporting cells and neurons of the nervous system. Thus, this summarizes the difference between neurofibroma and neurofibromatosis.

Reference:

1. “Neurofibromas.” Johns Hopkins Medicine.
2. “Neurofibromatosis.” AANS.

Image Courtesy:

1. “Back of a person with neurofibromas” By Seiradcruz at English Wikipedia (CC BY-SA 3.0) via Commons Wikimedia
2. “9913People with Neurofibromatosis in the Philippines 03” By JFVelasquez Floro – Own work (CC0) via Commons Wikimedia

ncG1vNJzZmivp6x7pbXFn5yrnZ6YsqOx07CcnqZemLyue9ahmK1lmah6tbTEZpuinpaav6a6wp5km52krLKmuoynnK6qn5u2o77OpphmmZ6Zeq%2Bx1Kumn6GSp7yurdOoqqKrXw%3D%3D