Understanding Neurofibromas: Causes, Symptoms, and Treatment Options
A neurofibroma is a non-cancerous (benign) tumor that arises from the nerve sheath, which is the protective covering surrounding nerves. It is primarily composed of Schwann cells, fibroblasts, and connective tissue. While neurofibromas can develop anywhere in the body, they are most commonly found on the skin’s surface or along deeper nerve pathways.
These tumors can occur as a single isolated growth (localized neurofibroma) or in multiples, often associated with a genetic condition known as neurofibromatosis type 1 (NF1).
Types of Neurofibromas
Neurofibromas are generally classified into three main types:
Cutaneous (Dermal) Neurofibromas
Appear on or just beneath the skin.
Usually soft to the touch and may feel like a small bump.
Often harmless and do not require treatment unless they cause discomfort or cosmetic concerns.
Diffuse Neurofibromas
Spread across a larger area of skin or tissue.
Commonly seen in children and young adults.
May cause localized thickening of the skin and sometimes disfigurement.
Plexiform Neurofibromas
Involve multiple nerve branches.
Often congenital (present at birth).
Can grow large and may lead to functional impairment or pressure on nearby structures.
More likely to develop into malignant tumors compared to other types.
Causes and Risk Factors
While isolated neurofibromas can develop spontaneously, multiple neurofibromas are often linked to NF1, a genetic disorder caused by a mutation in the NF1 gene on chromosome 17. This gene produces a protein called neurofibromin, which helps regulate cell growth. When the gene is faulty, cells can grow uncontrollably, leading to tumor formation.
Risk factors include:
Family history of neurofibromatosis type 1
Certain genetic mutations
Rarely, neurofibromatosis type 2 (NF2) and schwannomatosis
Symptoms
The symptoms of neurofibromas depend on their location, size, and type. Common signs include:
Small, soft lumps on or under the skin
Skin discoloration over the tumor (light brown or café-au-lait spots in NF1)
Tingling, numbness, or pain if the tumor presses on a nerve
In plexiform neurofibromas, large irregular masses that can cause swelling or deformity
In rare cases, neurofibromas can cause:
Weakness in nearby muscles
Loss of sensation
Pressure on internal organs or blood vessels
Diagnosis
Diagnosis usually involves:
Physical Examination – A doctor can often recognize neurofibromas by their appearance and feel.
Medical History – Discussion of family history and symptom onset.
Imaging Tests – MRI or CT scans to assess the size, depth, and involvement of surrounding structures.
Biopsy – Removal of a small tissue sample to confirm the diagnosis.
If multiple tumors are found, genetic testing for NF1 may be recommended.
Complications
While most neurofibromas are benign, potential complications include:
Cosmetic concerns (especially with visible skin lesions)
Pain or discomfort from nerve compression
Neurological symptoms if the tumor presses on spinal or brain nerves
Malignant transformation (rare) into malignant peripheral nerve sheath tumors (MPNST), especially in plexiform neurofibromas
Treatment Options
The treatment approach depends on tumor size, symptoms, and patient preference.
- Observation (Watchful Waiting)
If the tumor is small, painless, and not growing, doctors may recommend monitoring without immediate intervention.
- Surgical Removal
The most common treatment for symptomatic neurofibromas.
Involves carefully excising the tumor while preserving nerve function.
Risks include nerve damage, recurrence, and scarring.
- Medications
Currently, no drugs can eliminate neurofibromas, but research is ongoing.
For plexiform neurofibromas in NF1 patients, targeted therapies like selumetinib have shown promising results.
- Radiation or Chemotherapy
Rarely used unless malignant transformation occurs.
Living with Neurofibromas
For individuals with NF1, lifelong monitoring is essential. Regular check-ups can help:
Track tumor growth
Detect early signs of complications
Manage associated conditions like learning difficulties or scoliosis
Lifestyle tips:
Protect skin from injury to avoid irritation of neurofibromas.
Seek medical attention for any sudden increase in size, pain, or change in color of a tumor.
Join support groups for emotional and informational assistance.
Prognosis
Most people with isolated neurofibromas live normal lives without major complications. However, those with NF1 require ongoing care to manage multiple growths and reduce the risk of malignant transformation.
Key Takeaway:
A neurofibroma is generally harmless, but its impact varies depending on size, location, and genetic factors. With proper monitoring and timely treatment, most people can manage the condition effectively.
