# Use of Complementary and Alternative Medicine in the Management of Breast Cancer

## TL;DR

This study finds that combining complementary and alternative medicine with traditional breast cancer treatments may lead to worse survival outcomes compared to using traditional therapies alone.

## Contribution

The study provides new evidence on the impact of combining complementary and alternative medicine with traditional breast cancer therapies on patient survival.

## Key findings

- Patients using CAM in combination with traditional therapies were less likely to receive endocrine therapy and radiation.
- Combining CAM with traditional therapies was associated with higher mortality compared to traditional therapy alone.
- CAM alone or no treatment was linked to significantly higher mortality risks compared to traditional therapy.

## Abstract

This cohort study assesses the association of complementary and alternative medicine plus traditional therapies, including surgery, chemotherapy, radiation, endocrine therapy, and immunotherapy, with survival in female patients with breast cancer.

What is the association of complementary and alternative medicine (CAM) with survival in female patients with breast cancer?

In this cohort study involving 2 157 219 women with breast cancer, those who combined traditional therapies, such as surgery, chemotherapy, radiation, endocrine therapy, and immunotherapy, with CAM therapies were less likely to receive endocrine therapy and radiation compared with patients treated exclusively with traditional therapies. Combination of CAM and traditional therapies was associated with higher mortality compared with being treated exclusively with traditional therapy.

Findings of this study suggest that the use of CAM instead of traditional therapies could be associated with a reduction in survival in breast cancer, and further study is warranted.

Innovations in both the surgical and medical management of breast cancer over the past few decades have led to reductions in treatment-related morbidity and increases in overall survival. Despite these advancements in traditional therapies, including surgery, chemotherapy, radiation, endocrine therapy, and immunotherapy, a subset of patients continues to choose complementary and alternative medicine (CAM).

To describe the association of CAM with survival in patients with breast cancer.

This cohort study analyzed data from the National Cancer Database on female patients diagnosed with breast cancer from 2011 through 2021. Survival time was compared among patients who received traditional treatment, traditional treatment and CAM, and no treatment. Data were analyzed from May 2025 to December 2025.

Complementary or alternative treatment, defined in the NCDB as treatment administered by nonmedical personnel.

The primary outcome was 5-year survival. Unadjusted 5-year survival was assessed by Kaplan-Meier analysis, and adjusted survival was assessed with a Cox proportional hazards model controlled for age, race and ethnicity, Charlson Comorbidity index, insurance type, facility type, region, year of diagnosis, cancer stage, and income.

Of 2 169 202 female patients with breast cancer identified, 2 157 219 (median [IQR] age, 62 [52-71] years) were included in the sample. A total of 2 106 665 patients (97.6%) received traditional therapy, 273 (<0.1%) received CAM alone, 568 (<0.1%) received a combination of CAM and traditional therapies, and 49 713 (2.3%) received no treatment. Compared with patients treated with traditional therapies, those treated with CAM alone (adjusted hazard ratio [AHR], 3.67; 95% CI, 3.03-4.44; P < .001) or no treatment (AHR, 3.53; 95% CI, 3.48-3.58; P < .001) had the highest risks for mortality. Patients who received a combination of traditional therapies and CAM were less likely to receive endocrine therapy (eg, 40.7% vs 65.2% in stage II; P < .001) and radiation (59.5% vs 36.6% in stage II; P < .001) compared with patients treated exclusively with traditional therapies. Receipt of a combination of traditional therapies and CAM was associated with a higher mortality compared with being treated exclusively with traditional therapy (AHR, 1.45; 95% CI, 1.22-1.72; P < .001).

In this cohort study of data from female patients with breast cancer included in the NCDB, the use of CAM instead of traditional therapies was uncommon but was associated with a reduction in survival time. Further study is warranted.