Neurofibromas are a common type of peripheral nerve sheath tumoura tissue mass that forms from groups of unhealthy cells that develops on peripheral nerves that contain fibrous or connective tissuea group of cells that work together to perform a function. They are generally benignnot cancerous, can grow but will not spread to other body parts, solitary and sporadic (develop randomly without a genetic predisposition).
Peripheral nerve sheath tumours (PNSTs) are tumours that arise from the protective layer of peripheral nerves. More specifically, they develop from nerve sheaths, which are layers of myelin and connective tissue that provide insulation to nerve fibres within the nervous system.
The nervous system is made up of two primary components: the central nervous system (CNS), and the peripheral nervous system (PNS). The CNS is made up of the brain and spinal cord, and is responsible for all sensory and motor functions in the body. The PNS encompasses all nerves outside of the CNS, and is responsible for all involuntary functions in the body. The PNS is further subdivided into the autonomic nervous system (ANS) and the somatic nervous system (SNS). The ANS controls involuntary processes and glands, such as heart rate, bloodthe red bodily fluid that transports oxygen and other nutrients around the body pressure, respiration, and digestion. Comparatively, the SNS is responsible for voluntary and involuntary muscle movements, as well as transmitting sensory information to the CNS.
Neurofibromas are generally diagnosed equally among the sexes, and are generally diagnosed in people between the ages of 20-40. However, anyone can develop this disease.
Types of Neurofibromas
There are four primary types of neurofibroma, which are classified by the types of cellsthe basic structural and functional unit of all living things they develop from.
Intraneural Neurofibroma
Intraneural neurofibromas are the most common subtype of neurofibroma, and is categorised by the tumour developing inside the centre of the nerve. These tumours are generally found in patients between the ages of 20-30, and can be localisedaffecting only one area of body and/or nodular. Intraneural neurofibromas are generally benign, and can have a good prognosisto predict how a disease/condition may progress and what the outcome might be.
Localised/Nodular Cutaneous Neurofibroma
Localised and nodular cutaneous neurofibromas are a less common subtype of neurofibroma that develops within the dermis (middle layer of the skin) and subcutaneousunder the skin tissue (fatty tissue layer beneath the skin). These tumours are generally found in patients between the ages of 20-30, and can develop in any area of the body. Localised and nodular cutaneous neurofibromas are often benign, and can have a good prognosis.
Diffuse Cutaneous Neurofibroma
Diffuse cutaneous neurofibroma are a rare subtype of neurofibroma that develops within subcutaneous tissue beneath the skin. However, unlike localised cutaneous neurofibroma, these tumours are not well contained (or diffuse), and are generally diagnosed in children and young adults. Diffuse cutaneous neurofibromas are commonly misdiagnosed as plexiform neurofibroma, however these tumours are less likely to become cancerous. These tumours are generally benign, and can have a good prognosis.
Plexiform Neurofibroma
Plexiform neurofibromas are a rare subtype of neurofibroma that develops within the subcutaneous tissue beneath the skin, and are commonly confused with diffuse cutaneous neurofibromas. These tumours are generally diagnosed in early childhood, and have a strong association to neurofibromatosis type 1 (NF1). Plexiform neurofibromas tend to develop deeper into nerves and plexuses, and have a higher chance of undergoing a malignantcancerous, may grow and spread to other areas of the body transformation.
Treatment
When cancers are detected, they are staged and graded based on size, metastasiswhen the cancer has spread to other parts of the body, also known as mets, and how the cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs cells look under the microscope. Stagingthe process of determining how big the cancer is, where it started and if it has spread to other areas and grading helps your doctors determine the best treatment for you. However, as the neurofibromas are considered benign, these tumours are generally considered low-grade and not staged.
Once your tumour has been diagnosed, your doctor may recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including location, age, stage of disease and overall health.
Treatment options for neurofibromas may include:
- Surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence to remove as much of the tumour as possible.
- Watch and waitthe close monitoring of a cancer without giving treatment until symptoms appear or worsen.
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells.
- Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
- Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.
Risk factors
While the cause of neurofibromas remain unknown, the following factors may increase the likelihood of developing the disease.
- Having a family history of the disease.
- Being diagnosed with the condition neurofibromatosis type 1 (NF1).
Not everyone with these riskthe possibility that something bad will happen factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Symptoms
Neurofibromas may appear asymptomatic in the early stages of disease. If the tumour becomes malignant, or if the tumour is pressing on a nerve, you may experience:
- Pain in the affected area.
- Numbness and/or tingling in the affected area.
- Weakness and/or loss of function in affected area.
- Small, pea-shaped lumps under the skin.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis
If your doctor suspects you have a neurofibroma, they may order the following tests to confirm the diagnosisthe process of identifying a disease based on signs and symptoms, patient history and medical test results and refer you to a specialist for treatment:
- Physical examinationan examination of your current symptoms, affected area(s) and overall medical history.
- Neurological examinationan assessment of sensory and motor functions, such as vision, balance and coordination.
- Imagingtests that create detailed images of areas inside the body tests, potentially including:
- MRI (magnetic resonance imaging)a type of medical imaging that uses radiowaves, a strong magnet and computer technology to create detailed images of the body.
- CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.
- PET (positron emission tomography) scana type of medical imaging that uses radioactive tracers to create detailed images of the body.
- Blood teststesting done to measure the levels of certain substances in the blood.
- Electromyogram (EMG)a diagnostic procedure used to measure the response of nerves and skeletal muscles to electrical activity.
- Nerve conduction studiesa diagnostic procedure used to measure the speed of electrical impulses through a nerve.
- Biopsyremoval of a section of tissue to analyse for cancer cells.