Memorial Sloan Kettering and JNCI: Two American Studies Validate Electroacupuncture for 'Brain Fog' in Breast Cancer Survivors

Approximately 40% of breast cancer survivors develop treatment-related cognitive impairment — popularly called "brain fog" or chemo brain —, a condition that can persist years after the end of chemotherapy and the use of hormonal therapy. Difficulties with memory, attention, and processing speed compromise the quality of life, return to work, and emotional well-being of these patients. In less than five months, two randomized studies conducted by reference institutions in the United States published convergent evidence that electroacupuncture may offer a concrete therapeutic path for this problem — until now of difficult pharmacologic management.

The results of the Memorial Sloan Kettering study discussed below were presented at congress (SABCS, December 2025) and await peer-reviewed publication; this synthesis is preliminary in nature. The complementary UC Irvine study has already been published in the Journal of the National Cancer Institute (April 2026), but with a small pilot sample. The conclusions presented here should be interpreted in this context.

The first study, presented at the San Antonio Breast Cancer Symposium (SABCS) in December 2025 by Dr. Jun Mao (Chief of the Integrative Medicine Service at Memorial Sloan Kettering Cancer Center), randomized 260 breast cancer survivors — stages 1 to 3, more than 50% with prior chemotherapy and about 67% on hormonal therapy at the time of recruitment — into three arms: real acupuncture (n=129), standard care (n=61), and sham acupuncture (n=70). The protocol included weekly sessions for 10 weeks, with cognitive assessments at baseline, at the end of treatment, and at 26 weeks. The study was funded by the National Cancer Institute and the NCI Cancer Center Support Grant, conferring independent rigor.

The MSK study: distinguishing real effect from placebo effect

One of the most relevant findings of Dr. Mao’s study is the dissociation between subjective perception and objective cognitive performance. Both the real acupuncture group and the sham acupuncture group reported "clinically significant improvements" in the perception of memory, attention, and daily functioning — an expected result given the placebo effect inherent to any active care intervention. However, only the real acupuncture group demonstrated consistent improvement on standardized cognitive tests administered by a blinded team, evaluated at week 10 and at week 26. This separation between perceived effect and objective effect is methodologically robust and suggests, in preliminary analysis, that medical acupuncture may produce measurable cognitive changes beyond patient expectation.

The UC Irvine study in JNCI: neuroimaging evidence

The second study, published in the Journal of the National Cancer Institute on April 13, 2026 by Dr. Alexandre Chan (UC Irvine), adopted a different and complementary methodologic approach. The pilot RCT with 35 breast cancer survivors compared electroacupuncture targeted at specific neuropsychiatric acupoints (n=21) versus control acupoints (n=14), in 10 weekly sessions. The double-blind design — previously considered unfeasible in acupuncture studies — was achieved with the use of control acupoints unrelated to the neuropsychiatric system.

The results showed that 42.9% of participants in the specific acupoints group presented measurable objective cognitive improvement at the end of treatment, compared with 12.5% in the control group. Attention improvement was significant both at the end of treatment (Δ = 0.562) and at the four-week follow-up (Δ = 0.708), suggesting durability of the benefit. Psychological distress also improved significantly: 50% of participants in the specific group responded to treatment for the distress outcome versus 37.5% of the control. All adverse events reported were grade 2 or lower.

The differential of this study was the incorporation of structural and functional neuroimaging. Participants who received electroacupuncture at specific neuropsychiatric acupoints presented greater gray matter volume (P=0.033), and this increase correlated with attention improvement (r=0.69; P=0.020). Default Mode Network connectivity decreased (r=-0.93; P<0.01) — a pattern associated with better attentional focus — while Dorsal Attention Network connectivity increased (r=0.86; P<0.001), indicating favorable functional reorganization of brain networks (high correlation values in a small sample should be interpreted with caution).