People undergoing chemotherapy can experience considerable side effects, including nausea and vomiting, hair loss, mood changes and other health issues. New research shows 4 in 10 people who have chemotherapy also get severe peripheral nerve pain.
Peripheral nerve pain occurs when nerves outside the brain and spinal cord are damaged. Symptoms may include numbness in hands and feet that may spread to arms and legs, and sharp, throbbing pain. Extreme sensitivity to touch, muscle weakness, heat intolerance and drops in blood pressure also are symptoms, according to the Mayo Clinic.
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Chemotherapy has been known to cause damage to peripheral nerves, and sometimes the pain is chronic and severe enough that chemotherapy doses are reduced or discontinued. But prior research has not given a clear picture of the extent of chronic, painful chemotherapy-induced peripheral neuropathy.
A new meta-analysis of data from 77 studies across 28 countries – including nearly 11,000 patients – is the first study to offer a "comprehensive global estimate" of the prevalence of chemotherapy-induced peripheral nerve pain, or CIPN, and "its significant burden on patients worldwide," the researchers wrote. The study was published Tuesday in the journal Regional Anesthesia and Pain Medicine.
"Given the projected increase in cancer survivorship and the rising incidence of CIPN due to more aggressive chemotherapy regimens, understanding the global prevalence of chronic painful neuropathy in CIPN is critical," the researchers wrote.
Of the 10,962 people in the study with peripheral nerve pain after chemotherapy, 4,545 of them still had persistent pain after at least three months. People treated with platinum-based chemotherapy drugs had the highest prevalence of chronic CIPN at 40.5%. People treated with a class of chemotherapy drugs called taxanes, which inhibit the division and spread of cancer cells, had the second highest prevalence at just over 38%. People who had a combination of chemotherapy drugs called FOLFOX, used to treat colorectal cancer, had the lowest prevalence of persisting CIPN at 16.5%.
People treated with chemotherapy for lung cancer reported the highest prevalence of chronic CIPN. Those treated for ovarian cancer and lymphoma reported the lowest. These findings may have to do with the complex nature of lung cancer treatment, often with multiple, prolonged chemotherapy cycles, the researchers wrote.
The data analyzed for this study came primarily from research done in the United States and Japan. Studies from Asia included in the analysis had the highest prevalence of chronic CIPN, at nearly 47%, and those from Europe the lowest, at about 36%.
"The wide variability in prevalence rates across different countries, continents, chemotherapy regimens, and primary cancer history underscores the need for tailored strategies to address this debilitating condition," the researchers wrote.
Future studies should look at what is causing these discrepancies and find interventions for the debilitating condition, the researchers wrote.
