Complementary, alternative medicines associated with worse survival in breast cancer

By: Josh Friedman

From: healio.com

Key takeaways:

• Use of complementary and alternative medicines had a significant association with worse survival in breast cancer.
• Women who used these treatments had lower use of radiation and endocrine therapy.

Women with breast cancer treated with complementary and alternative medicines have significantly worse survival than those receiving traditional therapies, likely due to underutilization of proven modalities.

An evaluation of more than 2 million women with breast cancer showed those who reported treatment with complementary and alternative medicines (CAM) alone had more than 3.5 times higher likelihood of death in 5 years than those treated with traditional options.

Patients treated both traditionally and with CAM also had significantly worse OS, and had significantly lower utilization of radiation and endocrine therapy.

“We don’t have evidence in our study to say there are positives of alternative therapy,” Daniel J. Boffa, MD, MBA, division chief and professor of thoracic surgery at Yale School of Medicine, told Healio. “But, I suspect there are patients who benefit from alternative therapies, and the key is to strategically add them to traditional therapy as opposed to replacing them.”

‘A lot of potential’

Breast cancer incidence has slowly increased since the mid-2000s, including a 1% annual rise between 2013 and 2022, but mortality has decreased 44% from 1989 to 2023, according to American Cancer Society’s Cancer Statistics 2026 report.

Approximately 75% of the reduction in mortality could be attributed to improved treatments and screening.

“We’re using treatments that have less morbidity to patients and have less impact on their quality of life and function,” Boffa said.

Prior studies also have shown many patients with cancer use CAM, such as herbs and dietary supplements, acupuncture, and mind and body approaches, according to study background.

One survey of more than 3,000 individuals with cancer published in JAMA Oncology showed 33.3% had used CAM in the previous 12 months.

Healio has previously reported acupuncture significantly improved both perceived and objective cognitive function in patients with breast cancer.

“It’s not unusual for a doctor to try alternative medicines themselves, even for conditions they treat,” Boffa said. “They’re trying to lower their blood pressure with their diet or herbs, or before they go on a prescription. I see a lot of potential for alternative medicine.”

However, certain patients choose to use CAM in place of traditional therapies due to various factors, including mindset, religion and distrust in the health care system.

Boffa and colleagues decided to investigate whether use of CAM had survival implications within breast cancer using the National Cancer Database.

They included 2,157,219 women (median age, 62 years; interquartile range, 52-71; 76.2% white) diagnosed with breast cancer between 2011 and 2021.

Researchers defined CAM as that provided by nonmedical personnel.

Five-year OS served as the primary endpoint.

‘Substantial’ association

Nearly all patients received traditional therapy (97.6%).

Less than a tenth of a percent used CAM alone or in combination with traditional therapy, and 2.3% did not receive any treatment.

Women who received traditional therapy had the highest 5-year OS (85.4%), followed by combination (81.2%), CAM alone (60.1%) and no treatment (47.8%).

Compared with traditional therapy, all other treatment populations had significantly worse 5-year OS (CAM alone: adjusted HR = 3.67; 95% CI, 3.30-4.44; no treatment; aHR = 3.53; 95% CI, 3.48-3.58; combination: aHR = 1.45; 95% CI, 1.22-1.72).

“I was not expecting as substantial an association as was ultimately found,” Giorgio Caturegli, MD, general surgery resident and research fellow in the division of thoracic surgery at Yale School of Medicine, told Healio.

“We would have guessed the combination group would have the same survival, or potentially even an advantage because there are some known associations between complementary and alternative treatments and reducing side effects of different treatments,” Boffa added. “We thought perhaps patients might be able to take more traditional treatment and reduce the number of times that treatment was cut short.”

However, patients who received both traditional and CAM received certain therapies significantly less, including radiation (stage II: 59.5% vs. 36.6%; P < .001) and endocrine therapy (stage II: 40.7% vs. 65.2%; P < .001).

“Our takeaway isn’t that alternative treatments were harmful, it’s just that the patients who chose to combine them seemed more likely to forego some of the traditional treatment options,” Boffa said. “That’s probably why they were experiencing a worse outcome.”

Researchers acknowledged study limitations, including its observational nature and the high likelihood of underreporting of complementary and alternative medicines.

“There are several studies that indicate there’s a double-digit percent of patients who do some form of alternative therapy, and yet we were seeing a fraction of that,” Boffa said. “The concern is that patients don’t feel comfortable talking to their teams about their intentions to use alternative therapies. The downside of that is there’s a chance that there are a lot more patients we’ve categorized as being untreated who actually had alternative medicine and we didn’t know about it. We know that has a really suboptimal outcome.

“And, if there were patients we coded as being exclusively traditionally treated and some of them had alternative treatments because it wasn’t documented, we don’t have the ability to study them in great detail to say, these are the situations that the alternative was helping.”

Create a ‘safe space’

Boffa noted future studies could investigate survival impacts of CAM in other malignancy types, but of greater importance is clinicians creating a “safe space” to discuss these options with patients.

“It starts with greater awareness,” Caturegli said. “It’s not something that we are really trained in, or most people integrate into their daily practice.”

Caturegli acknowledged he typically has not discussed CAM with his patients, but he plans to start those conversations moving forward.

“Patients may be embarrassed,” Boffa said. “They may feel that the cancer teams do not have confidence in them, it may be upsetting for clinicians to talk about, or the cancer teams just don’t have any familiarity with complementary and alternative medicines. If the clinician asks the question, then there may be an exchange that could be helpful.”

Starting the conversation also could address any misinformation patients have encountered.

Healio previously reported approximately three-quarters of women with breast cancer encounter misinformation.

“The reality is you can find somebody saying just about anything you want to hear,” Boffa said. “There’s a real opportunity for confirmation bias. There are so many things that are spoken about, so many topics, that it’s really hard to understand what is true, what is noise, or what is just flagrantly untrue. You may not get the real story if you stop short. How you interpret things can very much influence how you communicate things and what is interpreted as true.

“There’s a real opportunity to improve shared decision-making by encouraging patients and clinicians to be more forthcoming in including this in their treatment conversations.”