Acupuncture vs Massage for Pain in Patients Living With Advanced Cancer: The IMPACT Randomized Clinical Trial

The IMPACT study is a pragmatic randomized clinical trial that compared the effectiveness of acupuncture versus massage for managing musculoskeletal pain in patients with advanced cancer. Conducted between September 2019 and February 2022 at cancer centers in the United States, including Memorial Sloan Kettering Cancer Center and Baptist Health Miami Cancer Institute, the study represents an important contribution to guidelines for the treatment of cancer pain. The context of the research is particularly relevant, considering that pain affects up to two-thirds of patients with advanced cancer and that the 2022 guidelines of the American Society of Clinical Oncology recommend acupuncture and massage as complementary modalities for cancer pain control. The study included 298 participants with a mean age of 58.7 years, 67.1% women, with various diagnoses of advanced cancer (78.5% solid tumors) and moderate-to-severe pain (mean score of 6.9 on a 0-10 scale).

Participants were randomized in a 1:1 ratio to receive acupuncture (n=150) or massage (n=148). The acupuncture protocol involved weekly 30-minute sessions for 10 weeks, followed by monthly booster sessions up to 26 weeks. Acupuncturists used 10-20 needles in at least 4 local points in the area of greatest pain, plus supplementary points, with electrical stimulation at 2 Hz at local points. The massage protocol followed the same duration, starting with breathing exercises and mobilizations, followed by 20 minutes of massage focused on the primary pain area, using techniques such as compression, myofascial release, and joint mobilization.

The primary outcomes showed that both therapies were effective in reducing pain. Acupuncture reduced the worst pain score by 2.53 points (95% CI: -2.92 to -2.15) and massage by 3.01 points (95% CI: -3.38 to -2.63) at 26 weeks. Crucially, there was no statistically significant difference between the groups (difference: -0.48; 95% CI: -0.98 to 0.03; p = 0.07), suggesting comparable effectiveness. More than half of the participants achieved a significant clinical response (improvement ≥30%): 55.2% in the acupuncture group and 65.9% in the massage group.

Secondary outcomes were equally encouraging, with both therapies improving fatigue, insomnia, and physical quality of life without significant differences between groups. Notably, there was a reduction in the use of analgesic medications, from 54.7% at baseline to 27.5% (acupuncture) and 35.6% (massage) at 26 weeks. The clinical implications are substantial. The study provides robust evidence that both modalities offer lasting benefits for a vulnerable population, with effects persisting beyond the active treatment period.

This is particularly important given the context of the opioid crisis and the need for nonpharmacological alternatives. Safety was excellent, with only mild adverse events: bruising (6.5%) and localized pain (5.8%) in acupuncture, and transient pain (15.1%) in massage. The study has important limitations. As a comparative effectiveness trial, it did not include a placebo or usual care control group, limiting the ability to determine how much of the improvement is specifically due to the interventions versus nonspecific effects.

The design did not allow participant blinding, although investigators and statisticians remained blinded to allocations. The COVID-19 pandemic interrupted treatments for some patients, but sensitivity analyses confirmed that this did not affect the main results. The rigorous training and monitoring of therapists may limit generalizability to community settings with greater variability in practitioner quality. The IMPACT study represents an important milestone in integrative oncology, demonstrating that both acupuncture and massage are viable and effective options for pain management in advanced cancer.

The results support current guidelines and provide evidence for informed clinical decisions, especially given that the population of people living with advanced cancer is growing due to therapeutic advances.