Photobiomodulation works for chemo-induced peripheral neuropathy

Photobiomodulation helps to reduce the severity of chemotherapy-induced peripheral neuropathy (CIPN) and increases mobility in cancer patients in a study presented at EAN 2023.

The strategy uses red or near-infrared light therapy to stimulate, heal, and regenerate tissues that have been injured during chemo.

CIPN is a serious and common debilitating side effect experienced by 68 percent of all cancer patients receiving chemotherapeutic agents, said study investigator Marithé Claes, a PhD student from Hasselt University in Hasselt, Belgium. “It is accompanied by both sensory and motor symptoms, including pain or seizure, and muscle weakness. Unfortunately, there are currently no fully effective management options for CIPN, and it is often necessary to prematurely stop the chemo or lower the dosage,” she added.

As photobiomodulation therapy is currently being used for oral mucositis and radio dermatitis in the clinic where Claes works, this has prompted her team to study its effects in CIPN.

Light therapy in 2 doses

Patients (n=60) included in the study had CIPN after completing a standard course of chemotherapy. They were randomly assigned to receive photobiomodulation at their palms and soles twice weekly for 3 weeks, at a dose of either 6 or 8 J/cm² at 2 weeks post-chemotherapy. [EAN 2023, abstract OPR-070]

The median age of the patients was 65 years; majority of them were women. The breast was the most common tumour location whereas paclitaxel was the most common therapy.

Prior to photobiomodulation, the patients were assessed using the modified Total Neuropathy Score (mTNS) and a range of patient-reported outcome measures (PROMs). They were also asked to do the 6-minute walk test (6MWT). During follow-ups, they were re-assessed using the same measures and a satisfaction numeric rating scale (NRS).

mTNS and 6MWT scores get better

“Both the lower- and higher-dose photobiomodulation were associated with significant improvements in mTNS scores compared with baseline,” reported Claes. “The same was true for the 6MWT, with significant improvements in both doses.”

Overall, patients were moderately satisfied with their treatment based on NRS scores, which slightly declined at 6-month follow-up. “Those who had improvements in their symptoms gave very high satisfaction scores, whereas those who had no improvement gave low scores. That explained the overall moderate satisfaction score,” explained Claes.

When asked if they would recommend photobiomodulation to other patients, the majority of them answered in the affirmative. However, the lack of a control group was considered a major limitation of the trial.

Moving forward

“Overall, we need larger trials with longer follow-up to determine the exact parameters of photobiomodulation that could be used in neuropathy treatment,” said Claes. “We also need to find out why some patients did well  with the treatment while others did not experience relief.”