Acupuncture May Improve Cognitive Symptoms in Breast Cancer Survivors

Credit: Adobe Stock/Africa Studio

At the 2025 San Antonio Breast Cancer Symposium, investigators presented new findings from the ENHANCE Phase 2 clinical trial, which explored whether acupuncture could help improve cognitive function in breast cancer survivors who also experience insomnia.

Many breast cancer survivors report ongoing cognitive difficulties after treatment, often described as “brain fog” or “chemo-brain.”

“Cancer-related cognitive difficulties can make performing daily tasks more difficult and can reduce overall quality of life,” explained lead investigator Jun J. Mao, M.D., MSCE, the Laurance S. Rockefeller chair in integrative medicine and chief of integrative medicine and wellness service at Memorial Sloan Kettering Cancer Center. “Unfortunately, there are very few treatments that are backed by evidence for this problem.”

These challenges can include trouble with memory, concentration, multitasking and finding words. According to the investigative team, more than 40% of breast cancer survivors experience some level of cognitive impairment, which can interfere with work, relationships and daily life long after cancer treatment ends. Previous research conducted by Mao and his team has shown that acupuncture can improve insomnia and may improve cognitive function among breast cancer survivors.

What Was the Goal of the ENHANCE Trial?

The goal of the ENHANCE trial was to determine whether acupuncture could improve both how patients feel about their cognitive abilities (perceived cognitive function) and how they perform on cognitive tests (objective cognitive function). Previous research suggested that sleep problems, especially insomnia, are closely linked to cognitive difficulties in cancer survivors and that acupuncture may help improve sleep.

To better understand acupuncture’s role, researchers compared real acupuncture, sham acupuncture and usual care.

“By comparing real acupuncture to sham acupuncture, and not just to usual care, we were able to better understand whether the benefits were due to the acupuncture technique itself or to the overall experience.”

Who Participated in the Study?

The trial enrolled 260 women who had been treated for Stage 0 to Stage 3 breast cancer and had no evidence of active disease. All participants reported moderate or greater cognitive difficulties and insomnia. They were randomly assigned to one of three groups:

1. Real acupuncture (129 participants)
2. Sham acupuncture (70 participants), designed to feel similar but without traditional acupuncture points or skin penetration
3. Usual care (61 participants)

Those in the acupuncture groups received weekly treatments for 10 weeks.

How Cognitive Function Was Measured

Researchers used two different tools to measure cognition:

• Perceived cognitive function was measured using the Functional Assessment of Cancer Therapy - Cognitive Function (FACT-Cog PCI) questionnaire, which asks patients how memory, attention and ability to perform tasks affect their daily lives.
• Objective cognitive function was measured using the Hopkins Verbal Learning Test-Revised (HVLT), a standardized test that evaluates memory, attention and learning.

Importantly, the researchers noted that perceived cognitive problems and objective test results often do not align. In this study, only about 30% of participants who reported significant cognitive difficulties showed measurable impairment on objective testing.

Key Findings on Cognitive Function

After 10 weeks, both real acupuncture and sham acupuncture led to clinically meaningful improvements in perceived cognitive function. Improvements were significantly greater than those seen with usual care alone. Real acupuncture continued to show stronger benefits compared with usual care at both 10 and 26 weeks.

When looking at objective cognitive testing, only real acupuncture led to measurable improvements. At 10 weeks, real acupuncture significantly outperformed sham acupuncture on memory test scores. While real acupuncture and usual care showed similar overall results, a subgroup of patients who had measurable cognitive impairment at the start of the study showed a promising trend toward better memory with real acupuncture.

Investigators believe real acupuncture may stimulate specific brain regions involved in memory and attention, though larger studies are needed to confirm this effect.

“Acupuncture should be seen as a complex intervention that involves both the needling and the care being delivered,” Mao said. “Just believing you’re receiving a helpful treatment and engaging in relaxation by lying down for 20 to 30 minutes can have potential therapeutic benefits even if the needles aren’t inserted or aren’t placed in specific therapeutic points.”

Acupuncture was generally safe, with mild bruising being the most common side effect. The study also found that insomnia and fragmented sleep were strongly linked to worse objective cognitive performance, reinforcing the importance of addressing sleep as part of cognitive care.