Acupuncture May Reduce Treatment-Related Joint Pain for Breast Cancer Patients

January 8, 2018, by NCI Staff

Acupuncture can reduce joint pain caused by drugs called aromatase inhibitors, according to results from a large, rigorous study of this approach in postmenopausal women with early-stage breast cancer.

Many women with hormone receptor (HR)–positive early breast cancers, which rely on estrogen to fuel tumor growth, take aromatase inhibitors after surgery to reduce their risk of the cancer recurring. These drugs, which block estrogen production, are also used to prevent breast cancer in postmenopausal women at high risk for the disease and to treat HR-positive metastatic breast cancer.

“About 50% of patients on these medications complain of some joint pain or stiffness, and about half of those patients describe the pain as severe,” causing some women to stop taking the drugs, said the trial’s lead investigator, Dawn Hershman, M.D., of Columbia University Medical Center.

Several small studies have suggested that acupuncture may alleviate aromatase inhibitor–related joint pain and stiffness, although others have shown no benefit, said Dr. Hershman, who presented the findings of the new study December 7 at the San Antonio Breast Cancer Symposium. She and her colleagues designed their large study to get a clearer answer to the question of whether acupuncture can relieve aromatase inhibitor–related pain.

“Identifying interventions to address aromatase inhibitor–induced joint pain is essential but has been lacking to date. This trial demonstrated that, compared with placebo, acupuncture may provide a durable, nonpharmacologic option for improving the musculoskeletal symptoms experienced by these patients,” said Raquel Reinbolt, M.D., a medical oncologist specializing in breast cancer with The Ohio State University Comprehensive Cancer Center, who was not involved with the study.

“Reducing the drug toxicity experience may then translate into improved adherence [to therapy], and ultimately, improved breast cancer outcomes,” Dr. Reinbolt said.

And, having acupuncture, along with engaging with the acupuncturist, as an alternative or in addition to taking prescription pain medications may help patients feel empowered to manage joint pain that can occur as a side effect of their cancer treatment, said Ann O’Mara, Ph.D., R.N., head of palliative care research in NCI’s Division of Cancer Prevention.

A major strength of the study is that it was a multisite trial and included many patients from general oncology practices, not just from university medical centers, Dr. O’Mara noted. This means the results are likely to be broadly generalizable to women in the community.

Pain Relief Continued after Treatments Ended

The clinical trial was led by the NCI-funded SWOG clinical trials group and carried out at 11 sites that participate in the NCI Community Oncology Research Program (NCORP). The 226 women in the trial were all taking a third-generation aromatase inhibitor—anastrozole (Arimidex®)^®, letrozole (Femara®)^®, or exemestane (Aromasin®)^®—after surgery for early-stage HR-positive breast cancer and were randomly assigned to receive true acupuncture, sham acupuncture (placebo), or no treatment.

Sham acupuncture involves shallow insertion of short, thin needles at non-acupuncture points.

All acupuncturists involved in the study were licensed and were rigorously trained on site by an acupuncturist on the study team. They were monitored for quality of care throughout the study.

To be enrolled in the study, women could not have taken opioid or corticosteroid drugs or received any alternative or physical therapy for AI-related joint pain in the past 4 weeks. Notably, Dr. Hershman said, 80% of the patients in the study were taking over-the-counter acetaminophen or ibuprofen for joint pain without experiencing relief.

Roughly half of the study participants (110) received true acupuncture twice a week for 6 weeks, followed by once-a-week maintenance sessions for 6 more weeks. The other half were in one of two control groups: 59 received sham acupuncture on the same schedule as the true acupuncture group, and the remaining 57 received no treatment.

The no-treatment group was included to control for any possible benefits or possible negative effects of the sham acupuncture, Dr. Hershman explained.

Study investigators followed the women for another 12 weeks after treatments ended. Patients reported on their pain before, during, and after treatment using various methods, including a questionnaire on which women could indicate a rating of “worst pain” on a scale of 0 to 10.

After 6 weeks, “we saw a mean two-point reduction of worst pain [in the true-acupuncture group compared with worst pain before treatment], which is a major reduction,” and these effects were maintained after 12 weeks, Dr. Hershman said.

Moreover, “even at 24 weeks, women in the true-acupuncture group had less pain overall than women in either [control] group,” Dr. Hershman added.

The main side effect of true and sham acupuncture was mild bruising, which was more common in the true-acupuncture group than in the sham-acupuncture group.

Patients in both the sham-acupuncture and no-treatment groups reported a roughly one-point mean reduction in worst pain at 6 weeks. Although it’s not clear why the control groups also saw an improvement, Dr. Hershman said that, in symptom-management studies where patients are monitored and assessed over time, researchers often see an improvement of symptoms in the control group.

More Investigations Planned

The new findings should make health care providers more likely to suggest acupuncture to their patients, Dr. Hershman said.

“Acupuncture is a safe and effective alternative approach for managing aromatase inhibitor–induced joint pain. The primary limitations of this treatment at the current time are cost and availability. Hopefully, this [new] data will generate additional discussion regarding reimbursement [by medical insurance] and access to treatment,” Dr. Reinbolt said.

One possible limitation of the study, Dr. O’Mara said, is that most participants (88%) were white, despite the inclusion of patients from across the United States. Only 5% and 7% of participants, respectively, were black or Asian.

As usual, some questions remain. “If you start having aches and pains, should you go back [for more acupuncture sessions]? Should you continue with, say, once-a-week treatments until you finish taking aromatase inhibitors?” Dr. O’Mara asked.

The team is not planning to pursue those questions. But, Dr. Hershman said, "We offered everybody 10 acupuncture sessions at the end of 24 weeks, regardless of which group they were in, and we’ll be doing a separate analysis to see how many patients in each group accepted the offer."

The team also plans to use tissue samples that they collected from patients throughout the trial to gain a better understanding of what causes aromatase inhibitor–related joint symptoms, "and what the mechanism of acupuncture may be in terms of providing pain relief," Dr. Hershman said.