The effectiveness and safety of acupuncture for chemotherapy-induced peripheral neuropathy: A systematic review and meta-analysis

Chemotherapy-induced peripheral neuropathy (CIPN) represents a significant and concerning side effect of oncologic treatment, affecting approximately 50% of patients who receive chemotherapy agents. This neurological condition can persist for years after treatment ends, causing debilitating symptoms such as tingling, pain, and coordination problems that drastically compromise the quality of life of cancer survivors. Currently, therapeutic options for CIPN are quite limited, with duloxetine being the only medication recommended by the American Society of Clinical Oncology guidelines, although with modest benefits. In view of this therapeutic limitation, acupuncture has emerged as a promising alternative, based on mechanisms that include modulation of neural pathways and neurotransmitters involved in pain control and autonomic regulation.

This study aimed to systematically evaluate the efficacy and safety of acupuncture in the treatment of chemotherapy-induced peripheral neuropathy through a systematic review and meta-analysis. The researchers conducted a comprehensive search in PubMed, Cochrane Library, and Embase databases from inception through April 2022, following PRISMA guidelines. Randomized clinical trials comparing true acupuncture with sham (placebo) acupuncture in patients with CIPN of grade greater than 1 were included. The methodology involved both manual acupuncture and electroacupuncture, defined as mechanical stimulation of specific body points.

Primary outcomes included validated scales to assess neurotoxicity, neuropathic pain, CIPN symptoms, and quality of life. For statistical analysis, the researchers used RevMan 5.3 software, calculating mean differences with 95% confidence intervals, applying fixed- or random-effects models according to data heterogeneity.

Five randomized clinical trials were included in the final analysis, totaling 225 participants. The results showed a mixed picture of acupuncture efficacy. Regarding neurotoxicity and associated functional dysfunction, measured by the FACT/GOG-Ntx scale, acupuncture did not demonstrate a statistically significant difference compared with sham acupuncture. However, for neuropathic pain control, assessed by the Brief Pain Inventory, acupuncture was superior to placebo in reducing pain intensity and pain interference with patients' daily activities.

This result was considered statistically significant and clinically relevant. Regarding CIPN-specific symptoms assessed by the numerical scale, there was no significant difference between the groups. Interestingly, regarding quality of life measured by the EORTC QLQ-C30 questionnaire, acupuncture showed significant improvement compared with placebo. In terms of safety, all studies reported an excellent safety profile, with only mild adverse events such as local discomfort, small bruises, or itching, and no serious adverse events related to treatment.

The clinical implications of these findings are important for both patients and healthcare professionals. For patients suffering from neuropathic pain due to chemotherapy, acupuncture emerges as a safe and potentially effective therapeutic option, especially considering the scarcity of effective pharmacological alternatives. The fact that acupuncture demonstrated specific benefits in pain control and quality-of-life improvement represents concrete hope for these patients. For healthcare professionals, these results suggest that acupuncture can be considered as part of an integrated therapeutic plan for the management of CIPN, particularly for pain control.

The excellent safety demonstrated makes acupuncture an attractive option, especially in patients who have already undergone intensive oncologic treatments. The protocols used in the studies, with sessions performed one to three times per week over 9 to 18 sessions, offer practical guidance for clinical implementation.

However, it is important to recognize the significant limitations of this study. The small sample size of the included trials limits the generalization of the results, and the heterogeneity found in some outcomes suggests caution in interpretation. In addition, the nature of the intervention makes it impossible to blind the acupuncturists, representing an inherent methodological limitation. The studies did not consider differences between chemotherapy types, doses, or tumor types, factors that could influence the results.

The sham acupuncture used as control may have its own biological effects, potentially interfering with the assessment of the actual efficacy of true acupuncture. Future studies will require larger samples, multicenter designs, and standardization of protocols to confirm these promising findings and establish more precise guidelines for the use of acupuncture in the treatment of chemotherapy-induced peripheral neuropathy.