A peripheral nerve tumor is a growth which starts on or within the nerve itself. Often, these tumors are benign. The tumor is generally a slow growing mass along the path of the nerve.
These tumors arise from the nerve itself, most commonly from their sheet (schwannoma), and less frequently from fibrous tissue within the nerve (neurofibroma). Depending on the type of tumor, surgical treatment may vary. Patients usually have slow growing mass along the path of the nerve that can be accompanied with various degrees of pain, numbness or sometimes muscle weakness. Physical exam, ultrasound and/or MRI can verify the presence of a nerve tumor. Biopsy prior to surgery is not recommended due to potential damage to normal nerve fibers.
Symptoms of a peripheral nerve tumor include:
- Varying degrees of pain
- Numbness
- Occasionally, muscle weakness
- Symptoms are related to the type and location of involved nerve, as well as the tumor’s size
Diagnosing a Peripheral Nerve Tumor
It is relatively simple to diagnose a peripheral nerve tumor. If suspected, your neurologist will perform a thorough physical examination to rule out other causes of your pain. You will most likely need to undergo an ultrasound or magnetic resonance imaging scan (MRI), to confirm involvement of the nerve. Patients generally do not need a biopsy before surgery, because the normal, healthy nerve fibers can be damaged. At this point, referral to a peripheral nerve surgeon experienced in treating peripheral nerve tumors is warranted.
Peripheral Nerve Surgery for Tumor Treatment
Surgery is usually necessary to remove the peripheral nerve tumor. Depending on the histological nature of tumor, the exact type of surgical treatment may vary. The goal is to remove the tumor without injuring the nerve itself. This is usually possible with schwannoma’s, but not with neurofibromas whose removal often requires excision of the involved segment of the nerve. After removing a segment of nerve, the nerve must be reconstructed. This reconstruction might be limited to a portion of the nerve (fascicle, as seen with schwannoma) or the entire nerve segment (as often required with neurofibroma). Once reconstructed, the nerve, under optimal circumstances, recovers approximately 0.5 to 1 mm/day. The use of microsurgical instruments and techniques, as well as a bloodless field, whenever possible, are important principles when seeking an optimal outcome.
Patients should be aware of timing and tumor growth concerns. Certainly, benign peripheral nerve tumors are slow growing and therefore might not be considered an urgent matter to have addressed. This reasoning is incorrect and problematic. Even though a tumor may be benign from a histological standpoint, it’s growth can still be devastating for the involved nerve. Moreover, when large tumor removal is attempted, the operation becomes much more challenging, with a higher likelihood of requiring complex reconstruction. This, in turn, can result in longer nerve recovery and ultimately may contribute to a less then optimal functional recovery when compared to removal of a smaller tumor. Considering the aforementioned, when peripheral nerve tumor is suspected and confirmed by MRI, timely referral a peripheral nerve surgeon is warranted.
During Peripheral Nerve Tumor Removal Surgery:
- You will receive anesthesia so you won’t feel any pain during the surgery.
- After the tumor is accessed, it is removed using microsurgical instruments and techniques, with care to identify and preserve as many healthy fascicles as possible. Those fascicles that are scarified with tumor removal should be immediately reconstructed, when possible
- If the tumor is neurofibroma and requires the entire segment of nerve to be removed, an immediate reconstruction should take place utilizing current nerve reconstruction algorithms. Nerve function with this will be lost distal to that segment, but hopefully all or at least partial function will be restored once nerve regenerates.
- As usual, the skin is closed in anatomical layers.
- Surgery for peripheral nerve tumor removal is usually an outpatient procedure. If surgery involves an extremity, ambulation is allowed immediately after the surgery, with crutches or a walker. Your dressing will stay on for about a week, while the sutures are removed three weeks later.
If you are not sure about your eligibility for surgery, and if you are not in the Washington, D.C. area, you can send me your records so I can determine if you are a good candidate for treatment. Visit my patient forms page for a downloadable form.