Irritation or damage to nerves outside the brain and spinal cord Causes difficulty in communication between nerves or group of nerves.
Post on 14-Dec-2015
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What is peripheral neuropathy (PN)?
Irritation or damage to nerves outside the brain and spinal cord
Causes difficulty in communication between nerves or group of nerves
What are peripheral nerves?
Long, wire-like fibers Transmit nerve impulses and sensory
information from the body to the spinal cord
Carry motor signals for muscle movement and other functions from the brain and spinal cord to rest of body and organs
What can cause PN?
Chronic diabetes and uremia Infection which affects nerves such as
shingles (post herpetic neuralgia) Excess alcohol Tumor pressing on a nerve Spinal cord injury Low vitamin B levels (especially B12) Poor circulation
What about cancer treatment?
Damage to nerves can occur with:› Surgery› Radiation therapy› Chemotherapy
Surgery
Can cause damage to nerves near the surgical site
Side effects reported with damage:› Burning› Shooting pain› Electric tingling› Numbness in skin around surgical site
Radiation Therapy
More common in 1960s with older treatments
Much less common today but still can occur
Side effects can include:› Weakness› Pain
Chemotherapy
Polyneuropathy most common form of neuropathy (affects several nerves)
Usually affects both sides of the body equally
Symptoms usually begin in feet and can progress to hands (referred as “stocking/glove distribution”)
Chemotherapy likely to cause peripheral
neuropathy Platinums (cisplatin, carboplatin,
oxaliplatin) Taxanes (Taxol or paclitaxel, Taxotere or
docetaxel) Epothilones (Ixabepilone or Ixempra) Plan alkaloids (vinblastine, vincristine,
vinorelbine, etoposide) Thalidomide and lenalidomide (Revlimid) Bortezomib (Velcade)
Symptoms of Chemotherapy Induced Peripheral Neuropathy (CIPN)
Pain (can be constant or come and go, shooting, electric or stabbing)
Burning Tingling (“pins and needles”) Numbness (decreased sensation of
pressure, touch, temperature) Increased sensitivity to temperature
(especially cold), touch or pressure
More symptoms of CIPN
Difficulty using fingers to pick up, hold or handle things such as buttons, writing
Problems with balance Tripping or stumbling with walking Shrinking or weak muscles Loss of or reduced reflexes
Less common symptoms
Difficulty swallowing Urinary incontinence Constipation Impotence Dizziness with standing
How common is CIPN?
3-7% in those treated with single agents
38% in those treated with multiple agents
When do symptoms start?
Can begin anytime after treatment starts
Sometimes occurs at end of treatment Can worsen as treatments go on
How long do symptoms last?
Can be short term› Last a few days› Stop after treatment ends
Can be long term› Persist between treatments› Continue 6-24 months after treatment
ends Can become a permanent problem
What affects PN longevity?
Age Genetic predisposition Chronic conditions (diabetes, kidney
failure, HIV) Amount of each dose of chemo Total dose of chemo Drug combination Previous chemo Previous problems with PN
First Step
Talk to your doctor or nurse immediately after symptoms begin
Do not delay telling Failure to disclose symptoms can lead
to life-altering problems
What may your doctor do?
Reduce dose of chemo (this is safe and still give you the same benefit as higher doses)
Give smaller doses 2-3X vs. 1X per week
Give dose over longer period of time Give longer breaks between chemo Alter chemo cycle
What can you do to stay safe if affected by PN?
Wear gloves and warm socks especially in the cold
Wear shoes inside and outside your home Protect your hands when working Keep your house well lit/keep night light Use nonskid surface in shower/tub Clear floor of objects and watch for rugs Test temperature of water with non-
affected body part Check your feet at end of each day
What else can you do?
Avoid alcohol If diabetic, control your blood sugar Treat your pain as prescribed Pay attention to your shoes Sit down as much as possible if feet are
a problem
Prevention of and treatment for CIPN?
Several preventions and treatments have been tried with mixed results
There is no sure way to prevent CIPN to date
Mixed results with treatments Research needs to continue
Vitamin E
Antioxidant May protect nerves from damage due to
cytotoxic drugs 3 studies examined effect giving 300 to
600 mg during and 3 mths after treatment ended
Evidence of less nerve damage in group who took Vitamin E
Other study found deficient Vitamin E levels in pts receiving cisplatin who had PN
Calcium and Magnesium
Tested in pts who received oxaliplatin which binds to calcium and magnesium
Given 1g of calcium and magnesium before and after infusion
65% of those treated vs. 37% of non-treated had no PN symptoms
Retrospective, nonrandomized study
Chemoprotectants
Amifostine which detoxifies chemotherapy drugs and facilitates DNA repair
Three studies examined effect on PN No differences in sensory or motor
symptoms found in pts treated with amifostine
Anticonvulsants
Carbamezapine (Tegretol) with oxaliplatin
No neuropathy in treated group vs. 30% in historical control group
Need placebo controlled trial
Glutamine
Nonessential amino acid Thought to have neuroprotective
effects for paclitaxel 8% of those treated vs. 40% not
reported PN symptoms in one study (10g daily)
Other study (10 g 3X/d) in those treated noted less symptoms
Larger, randomized, placebo studies needed
Glutathione
Thiol tripeptide may hamper platinum accumulation in nerves
Three studies to date 1st 1500 mg/m2 IV, no grade 3-4 toxicity 2nd 3 g/m2, 58% vs. 39% able to receive
all cycles of chemo and improved QOL 3rd 1.5 g/m2 17 vs. 88% had clinical
evidence of PN Need further randomized trials
Alpha lipoic acid
Fatty acid which converts sugar into energy and is also an antioxidant
Some studies with diabetics 4 randomized, double-blind, placebo
controlled studies 600 mg/d IV Clinically significant improvements in
pain, burning and numbness after 5 wks Need studies for CIPN
Acetyl L-carnitine
Nutritional supplement which functions as an antioxidant
2 studies in pre-existing CIPN 1 g/d IV or 1 g/tid orally Studies limited by small sample size
and not randomized
Tricyclic antidepressants
Nortriptyline – blocks reuptake of serotonin and norepinephrine in pain modulating system of CNS
Analgesic effect Escalating dose of up to100 mg/d Modest benefit in study of cisplatin
induced PN
Treatment for nerve pain
Antidepressants (amitriptyline, nortriptyline, and desipramine)
Anticonvulsants (gabapentin or Neurontin, pregabalin or Lyrica)
Steroids (short term use only) Local anesthetics (capsaicin, EMLA,
lidocaine 5%) Opioids and methadone
Which approved?
Only ones approved by FDA for treatment of neuropathic pain› Duloxetine (cymbalta) – diabetic PN› Pregabalin (lyrica) – diabetic PN and post
herpetic neuralgia› Lidocaine patches 5% - post herpetic› Gabapentin (neurontin) – post herpetic
Non-pharmacology Interventions Studied
Acupuncture Assistive devices Physical activity and exercise Pulsed infrared light therapy Transcutaneous nerve stimulation Spinal cord stimulation
Other approaches
PT - can help improve balance, strength and safety
OT – can help improve fine motor coordination such as writing and help adapt your home and work environment
Pain specialists – can educate you about treatment options and help manage your symptoms
Podiatrist – can help you find the right shoes for your symptoms
Emotional support
Talk to your oncology team Consider support groups Visit respected internet websites
› cancer.gov› cancer.org› neuropathy.org› cancercare.org› lbbc.org
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