Peripheral neuropathy is caused by damage to your peripheral nerves, which are not located in the brain, or spinal cord. They are found throughout your body, and help you feel things. They also control the function of your organs. The damage is usually to nerves in the hands, feet, arms, and legs.

Cancer treatments are meant to kill cancer cells, but a side-effect is that normal cells can be damaged or killed too. When chemotherapy damages peripheral nerves, it is called chemotherapy-induced peripheral neuropathy, or CIPN. Other types of cancer treatments can also cause it.

What Cancer Treatments Cause Peripheral Neuropathy?

Drugs for cancer treatment are the most common cause. But surgery, radiation, the tumour pressing directly on nerves, chemicals released by tumours, and infections can be contributors as well.

Symptoms

There are three types of peripheral nerves: sensory, motor, and autonomic. If damage occurs to sensory nerves, you may feel pain, tingling, or numbness. If it’s mainly the motor nerves affected, you may feel weak or off-balance. You may have constipation or dizziness with damage to the autonomic nerves; they control organ function.

Symptoms tend to start in the fingers and toes, progressing to hands and feet, then arms and legs. It can become hard to pick things up, hold on to things, walk, and perform tasks like buttoning your shirt.

Any time after your treatment starts, symptoms may suddenly be experienced. They’re usually mild at the beginning, but slowly worsen. Also, they get better slowly, usually over the course of a few months. Unfortunately, sometimes the damage is permanent and they do not go away.

Common symptoms are:

• – Tingling
• – Numbness
• – Weakness
• – Cramping
• – Burning
• – Pain (may be there all the time or may come and go, like shooting or stabbing pain)
• – Not being able to feel things that are touched
• – Not being able to sense cold or heat
• – Sensitivity to cold or heat or touch
• – Feeling off balance
• – Having trouble walking
• – Dizziness
• – Constipation

Tell your doctor or podiatrist as soon as possible if you experience any of these.

 Who is at Increased Risk?

Thirty to forty percent of patients treated with chemotherapy develop some degree of peripheral neuropathy. Doctors cannot predict who will be affected, but some things make you more susceptible:

• – Having had chemotherapy, radiation, or surgery before
• – Needing a high dose, or long course of treatment
• – Taking more than one drug that can cause neuropathy
• – Having a history of alcohol abuse
• – Being a diabetic
• – Having HIV or AIDS
• – Having severe malnutrition
• – Having multiple myeloma, lymphoma,  lung, or breast cancer
• – Having nerve damage from previous injury or illness.

How is it Diagnosed?

Tell your doctor or podiatrist if you think you have peripheral neuropathy. They may watch you walk and test your reflexes, strength, and ability to feel touch. They may also perform nerve conduction tests, which measure the strength and speed of electrical signals sent by your nerves, in response to small shocks.

Can Peripheral Neuropathy be Prevented?

There is no proven way to prevent nerve damage in patients undergoing treatment. It probably helps to give less of the cancer drug. “Stop and go” schedules are also being tested internationally, to see if a pre-planned break in treatment prevents neuropathy, without reducing the effectiveness of the cancer treatment.

Many drugs and supplements are being tested for prevention, to aid patients with cancer. Results have been mixed, so more research is needed. Some prevention treatments being tested are:

• – Calcium and magnesium infusion
• – Vitamin E
• – Vitamins B1 and B12.

Check with your doctor before taking any supplements. They can make your cancer treatments work less well, and might cause problematic side effects, especially if taken at the wrong dose.

If you develop neuropathy symptoms during treatment, your treatment might be stopped. Your treatment can be restarted after you feel better, or if the tumour starts to grow again. This treatment break can prevent the nerve damage from getting worse. Without it, your symptoms might worsen, and become permanent.

 How is Peripheral Neuropathy Treated?

There are no treatments for peripheral neuropathy that fix the nerve damage. Instead, treatment is given to relieve and manage symptoms. And unfortunately, many of the treatments have not proven to help, but have side effects of their own. Many patients do find relief, however, with combinations of drugs, dietary supplements, and other types of therapy.

Some of the same drugs and supplements being studied for prevention are also used for treatment.

Your doctor may prescribe drugs to help manage the symptoms, such as:

• – An antidepressant for tingling and numbness
• – An anticonvulsant for pain
• – A muscle-relaxant
• – An analgesic
• – A steroid for short-term use
• – Lidocaine patches
• – Opioids for severe pain
• – A gentle laxative for constipation

Your doctor may recommend some dietary supplements, such as:

• – A combination B vitamin
• – Folic acid
• – Magnesium
• – Glutamine

There are other treatments that may help you manage your symptoms, including:

• – Electrical therapy (where nerves are stimulated to release endorphins with a gentle electrical current)
• – Occupational and/or physical therapy
• – Massage therapy
• – Exercise
• – Acupuncture

What Else Can I Do?

When you cannot feel your hands and feet, you are at risk for injuries. Also, injuries can go unnoticed and become infected. You must be careful to protect yourself. Here are some things you can do:

• – Wear good footwear to protect your feet from injury
• – Wear gloves when using your hands, for injury protection
• – Inspect your skin for injuries at least once each day
• – Be extra careful when handling sharp objects or hot liquids
• – Be extra careful on stairs; use the handrail
• – Use non-skid surfaces in the bath and other slippery spots
• – Use a cane or other device if you have trouble with balance
• – Ask for help

Additionally, avoid alcohol; it can make symptoms worse. Finally, try to ensure you get the emotional support you need.

 Your feet mirror your general health . . . cherish them!