Removal of a schwannoma and peripheral nerve tumours in Zaporizhzhia
Most often these are benign growths of the nerve sheath - schwannomas (also called neurinomas) and neurofibromas. The recognisable sign is a small firm lump under the skin which, when pressed, sends a shock along the nerve, down to the fingers. The lump moves across the nerve but not along it, and over time numbness and weakness appear in that nerve's territory.
Such tumours can usually be removed with the nerve itself left intact.
- Symptoms
- a lump under the skin, a jolt on pressing it, numbness
- Work-up
- ultrasound of the nerve, MRI with contrast, nerve conduction study
- Without surgery
- a small mass without symptoms and without growth - observation
- Surgery
- microsurgical removal with preservation of the nerve
- Consultations
- room 211, Mon-Fri 08:30-15:00
- The mass is growing quickly over weeks and months.
- Weakness is increasing in the muscles that nerve supplies.
- The pain has become constant and painkillers do not control it.
- The mass is hard and fixed, tethered to the surrounding tissue.
- Multiple masses along different nerves - this needs a separate work-up.
Most such tumours are benign and grow over years. Rapid growth is the exception that has to be checked without delay.
What a peripheral nerve tumour is
A nerve is wrapped in sheaths, and it is from their cells that these masses most often grow.
A schwannoma grows from the Schwann cells that form the myelin sheath. It usually pushes the nerve fibres aside rather than growing between them - and that is essential: such a tumour can often be removed with the nerve left intact.
A neurofibroma grows between the fibres and is harder to separate. Multiple neurofibromas can be a manifestation of neurofibromatosis - a hereditary condition requiring its own follow-up.
Malignant nerve sheath tumours are rare. Rapid growth, pain and an increasing neurological deficit are what raise the suspicion.
Symptoms
- A firm mobile lump under the skin, usually on a limb.
- On pressing it, a jolt or an electric shock sensation along the nerve. This is the most characteristic sign.
- Numbness or tingling in the area the nerve supplies.
- Weakness of the corresponding muscles - with long-standing compression.
- Aching pain at rest, sometimes at night.
- The mass moves across the nerve but not along it - a detail noticed on examination.
Causes
In most cases the cause is unknown: the tumour arises spontaneously.
Multiple masses are typical of neurofibromatosis types 1 and 2 - hereditary conditions. In that case follow-up by other specialists is needed as well.
The role of injury is debated: sometimes a mass appears in the area of a past injury, but in most cases there is no direct link. It is worth distinguishing a tumour from a traumatic neuroma - an overgrowth at the end of a damaged nerve, which is not a tumour.
How we diagnose it
Ultrasound of the nerve is the first and most accessible investigation. It shows whether the mass is connected to the nerve, and its size and structure.
MRI with contrast is the main one. It gives the exact location, the relationship to the nerve and the surrounding structures, and signs of benignity.
A nerve conduction study assesses how far conduction is impaired. That matters both before the operation and for comparison afterwards.
A biopsy before surgery is usually not done: trying to take a sample with a needle through the nerve can damage it. The histological diagnosis comes from the removed tissue.
The ultrasound and the contrast MRI if they have been done, and the nerve conduction study results. If you have none of that, we start with the examination and I will say what is needed next.
Bring the scans on a disc or a flash drive - I look at the images themselves, not the report: what to bring and on what.
I see patients in Zaporizhzhia, room 211. If the lump has already been examined by ultrasound, bring the report.
How we treat it
Watchful waiting
Medication for pain
Microsurgical removal
Resection with nerve grafting
Indications for surgery
- The mass is growing.
- There is pain that lowers quality of life.
- A neurological deficit is increasing - numbness, weakness.
- A histological diagnosis is needed.
- There are features suspicious for malignancy.
The main option is microsurgical removal with preservation of the nerve: the tumour is dissected out of its fascicles under the microscope. When the nerve cannot be preserved, the gap is closed with a graft.
After a schwannoma is removed with the fibres preserved, function is usually unaffected, or dips temporarily and recovers within weeks.
If some fibres had to be divided, lasting numbness in the supplied area is possible. Strength returns more slowly and not always fully - as with any nerve damage, recovery proceeds at about a millimetre a day.
The sutures come out after about two weeks, and the limb is spared heavy use for four to six weeks.
Questions
Is it cancer?
In the vast majority of cases no: schwannomas and neurofibromas are benign. The final answer comes from histological examination of the removed tissue.
Can surgery be avoided?
If the mass is small, is not growing and causes no symptoms - yes, it can be observed. The decision is made on how it behaves, not on the mere fact of the finding.
Will numbness remain after the operation?
When a schwannoma is removed with the fibres preserved, usually not. If fibres had to be divided, a numb patch can remain. That is discussed before the operation, not after.
Why does pressing that little ball send a jolt?
Because the mass is connected to the nerve, and pressing on it irritates the fibres. That is the characteristic sign that distinguishes these tumours from ordinary lumps under the skin.
Will it come back?
A schwannoma removed completely usually does not return. In neurofibromatosis new masses can appear elsewhere - that is a feature of the disease, not a failure of the operation.
Call me and I will tell you what to do next
Mon-Fri 08:30-15:00. On operating days I cannot answer the phone: message the same number instead.
+380 67 901 37 01How it is treated
Procedures used for this condition. Each page covers how it goes, who it suits and how long recovery takes.
Dmytro Ivakhnenko - spine neurosurgeon in Zaporizhzhia
Spine neurosurgeon of the highest category, PhD in Medicine, associate professor, 30 years in practice. Spine and nerve surgery in Zaporizhzhia.