Peripheral nerve damage (peripheral neuropathy)
The nervous system is made up of the central nervous system and the peripheral nervous system. The central nervous system is made up of the brain and spinal cord. The peripheral nervous system includes the nerves outside of the brain and spinal cord. Sometimes cancer or its treatment can damage the nervous system. Damage to the nerves of the peripheral nervous system is called peripheral neuropathy.
Peripheral neuropathy can be caused by:
- some types of chemotherapy drugs such as cisplatin (Platinol AQ), oxaliplatin (Eloxatin), carboplatin (Paraplatin), docetaxel (Taxotere), paclitaxel (Taxol), vincristine (Oncovin, Vincasar), vinorelbine (Navelbine) and vinblastine (Velban)
- some types of targeted therapy drugs such as bortezomib (Velcade) and thalidomide (Thalomid)
- a tumour growing into or pressing on a peripheral nerve
- radiation therapy
- poor nutrition
- paraneoplastic syndrome – symptoms that occur when substances released by cancer cells disrupt the normal function of nearby or distant organs or tissues
You may have a higher risk of developing peripheral neuropathy if you:
- have diabetes
- drink large amounts of alcohol
- have an autoimmune condition such as rheumatoid arthritis or lupus
- have an underactive thyroid (called hypothyroidism)
- have kidney problems
- are under extreme stress
Symptoms of peripheral neuropathy depend on which nerves are affected and how bad the injury is to the nerves. Symptoms include:
- numbness, tingling (pins and needles) or burning sensation in the hands or feet
- pain that is medium or severe
- unusual sensations such as heat or burning when touching something cold
- pain or discomfort when your body is touching something like being covered with a blanketor in your feet when you’re wearing shoes
- muscle weakness that causes you to have trouble walking, climbing stairs, doing up buttons or brushing your teeth
- muscle cramps
- clumsiness or having trouble with knowing where your hands and feet are in space (loss of sense of position), especially when trying to walk or pick up objects
- constipation or bloating
- dizziness, blurred vision, trouble hearing or trouble chewing if the nerves in the head are affected
- erectile dysfunction or difficulty urinating
- changes in sweating
Peripheral nerve damage may be temporary but it may take a few months or even years before it goes away. Sometimes, peripheral nerve damage may be permanent.
If symptoms get worse or don’t go away, report them to your doctor or healthcare team without waiting for your next scheduled appointment.
Your doctor will try to find the cause of peripheral neuropathy. If you are taking a drug or treatment that is known to cause peripheral neuropathy, your doctor will monitor you for signs of nerve damage before each treatment.
Your doctor may do tests to see how well your nerves are working, such as:
- doing a neurological exam to check reflexes, muscle strength and see if there are any signs of numbness
- nerve conduction studies to check the severity and location of the nerve damage
- electromyography (EMG) – checks the electrical signals of the nerves to the muscles
Your doctor may do other tests to check your:
- balance and coordination
Managing peripheral neuropathy
Your healthcare team can suggest ways to manage peripheral neuropathy based on the cause of the damage and the symptoms you’re having. Your doctor may stop or lower the dose of a drug that is causing the peripheral neuropathy to prevent permanent damage. For most people, symptoms will start to get better over time but sometimes this damage will be permanent.
Your healthcare team can suggest ways to manage peripheral neuropathy, such as:
- medicines to help relieve nerve pain or discomfort, such as gabapentin (Neurontin), amitriptyline (Elavil) or pregabalin (Lyrica), or other pain-relieving medicines
- physiotherapy or occupational therapy to help you keep muscles strong and improve coordination and balance
- getting regular exercise
- massage therapy
- eating a well-balanced diet rich in vitamins and antioxidants and drinking plenty of fluids
- relaxation exercises
- medicines to help relieve constipation
Tips for protecting yourself and managing peripheral neuropathy in your daily life
If you have peripheral neuropathy, you will need to learn ways to cope with the symptoms.
- Be careful with sharp, hot, cold or other dangerous objects if your fingers are numb.
- Check your feet regularly for cuts or other wounds. People with neuropathy can be at risk for infection and poor wound healing.
- Move slowly and use handrails when going up and down stairs if muscle strength or balance is affected.
- Make sure all rooms, stairways and hallways are well lit.
- Remove objects that could cause you to trip or fall.
- Use assistive devices such as grab bars and skid-free bath mats for showers and tubs.
- Clean up any spills right away so you don’t slip.
- Use dishes that won’t break.
- Make sure you can feel the steering wheel and gas and brake pedals if you drive.
- Use a cane or walker to help with stability when you walk.
- Wear gloves and socks in cold weather.
- Don’t walk in bare feet.
- Make sure water isn’t too hot. You can test the temperature with your elbow. Turn the taps down to a lower setting or get a temperature control device added to your taps to keep the water cooler.
- Get up slowly so your body has time to adjust to a change in position.
Tips to help you cope emotionally
Dealing with peripheral neuropathy can lead to feelings of anger, sadness and frustration. It takes time and patience to deal with these feelings, but they should get better if you find a helpful treatment and as you adjust to these changes.
You may find it helps to share your feelings with someone close to you. You can also talk to your healthcare team to see what type of counselling or support groups are available.
Any substance that help protect cells from damage caused by free radicals (unstable molecules made during metabolism, which is the chemical processes needed for cell function, growth and reproduction).
Great progress has been made
Some cancers, such as thyroid and testicular, have survival rates of over 90%. Other cancers, such as pancreatic, brain and esophageal, continue to have very low survival rates.