Plagued by pain related to chemotherapy

Yogini Patel tried for eight years to walk without pain, but every step she took was excruciating.

“It was torture,” she says. “Like walking on a bed of nails.”

It turns out the chemotherapy drugs that were keeping Patel's breast cancer at bay for years were also attacking the nerves in her feet, causing a condition called chemotherapy-induced peripheral neuropathy.

“Chemotherapy drugs are formidable weapons in the battle against cancer,” says Sal Abdi, M.D., Ph.D., chair of Pain Medicine at MD Anderson. “But the drugs can't distinguish between healthy and cancerous cells. This means normal cells are damaged along with cancer cells.”

Nerve cells are especially sensitive, Abdi explains, and easily injured. Symptoms of nerve damage start first in the hands and feet, then move toward the center of the body.

Patel says the pain was the hardest part of her cancer treatment. “Every step I took was agony,” she says. “

Tears fell from my eyes.

Patel’s experience is not uncommon.

It's estimated that as many as 90 percent of patients who receive chemotherapy suffer from chemo-induced peripheral neuropathy.

Some begin experiencing it with the first dose of chemo, while others don't feel it until late in their treatments. Some have mild symptoms, while others' are more severe.
Some continue to suffer well after treatment has ended. For others, the neuropathy ends as soon as chemo stops.

Symptoms also vary.

Some patients have pain, but some only feel numbness, tingling and a loss of sensation.

Sometimes their hands and feet get cold; sometimes they're hot. Some people feel as though something heavy is sitting on their legs. Others feel like they're walking on broken glass.

“Every case is different,” Abdi says.

“Because neuropathy is caused by nerve damage, its effect on you depends largely on how well your nerves recover. And that depends on the length of your treatment, the intensity of your chemo dosage, the extent of your nerve damage, and genetic factors that make some people more susceptible to the side effects of chemotherapy.”

To help patients such as Patel, Abdi is working with a new type of pain treatment that is free of drugs and side effects.

Scrambler therapy, as it's called, uses low doses of electrical stimulation to reset — or “scramble” — pain messages being sent to the brain.

Electrodes connected to the scrambler device are placed on the patient's skin near damaged nerves. When the scrambler is turned on, the electrodes begin sending non-pain messages to the brain to replace pain messages.

The new signals break the pain cycle and retrain the brain to understand that it's not really experiencing pain. 

The therapy is delivered for 10 days in 45-minute sessions, and can be repeated if needed. Pain typically begins to lessen within five to 10 minutes during the first session.

Healing the hurt

“The benefit lasts for at least several months,” Abdi says, “and when patients' pain comes back, it's never as bad as it was prior to treatment. The results we’re seeing are phenomenal.”

Abdi recently completed testing the treatment on more than 20 patients, including Patel.

He and his colleagues are planning a new study in which patients will be followed for at least six months to determine the long-term effects of the therapy.

Patel, for one, is sold.

Read more about MD Anderson doctor's work with “neuromodulation” therapies that train the brain to do something different than what it is currently doing by using feedback, stimulation or other non-drug means in Conquest magazine.