Complementary therapies in early breast cancer: Oncologists’ evidence-based decisions in a Southeast European vignette survey

Teo Buhovac; Žarko Bajić; Mario Nalbani; Lazar Popović; Milan Risteski; Nikola Milašević; George Dimitrov; Anes Pašić; Marija Karaga; Eduard Vrdoljak

doi:10.17305/bb.2025.13413

Authors

Teo Buhovac Oncology Clinic, University Clinical Hospital Mostar, Faculty of Medicine, University of Mostar, Mostar, Bosnia and Herzegovina https://orcid.org/0000-0003-4539-4093
Žarko Bajić Research Unit "Dr. Mirko Grmek", University Psychiatric Hospital "Sveti Ivan", Zagreb, Croatia; Biometrika Healthcare Research, Zagreb, Croatia.
Mario Nalbani Department of Oncology, General Hospital Dubrovnik, Dubrovnik, Croatia
Lazar Popović Oncology Institute of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia https://orcid.org/0000-0002-3278-6875
Milan Risteski Zan Mitrev Clinic, Skopje, North Macedonia
Nikola Milašević Institute for Oncology, Clinical Centre of Montenegro, Podgorica, Montenegro https://orcid.org/0009-0008-5172-3379
George Dimitrov Department of Medical Oncology, University Hospital “Tsaritsa Yoanna – ISUL”, Medical University of Sofia, Sofia, Bulgaria https://orcid.org/0000-0002-9925-9025
Anes Pašić UPMC Hillman Cancer Centre Croatia, Bračak, Croatia https://orcid.org/0009-0004-4924-373X
Marija Karaga Oncology Clinic, University Clinical Hospital Mostar, Faculty of Medicine, University of Mostar, Mostar, Bosnia and Herzegovina
Eduard Vrdoljak Clinical Hospital Centre Split, School of Medicine, University of Split, Split, Croatia

DOI:

https://doi.org/10.17305/bb.2025.13413

Keywords:

Integrative medicine, integrative oncology, breast neoplasms, complementary therapies

Abstract

Complementary therapies are increasingly integrated into the framework of integrative oncology. While numerous complementary therapies provide potential benefits, some may also carry risks, including interactions with conventional cancer treatments. The degree to which oncologists' real-world decisions regarding complementary therapies align with evidence-based guidelines remains uncertain. This study aimed to evaluate oncologists' evidence-based decisions on whether specific complementary therapies should be prohibited, permitted, or recommended for early breast cancer treatment. We conducted a cross-sectional online survey that included a randomized vignette experiment involving oncology specialists and residents from seven Southeast European countries. The primary outcome was the percentage of accurate classifications of 28 therapy-indication pairs in neoadjuvant and adjuvant settings, benchmarked against published evidence. Correctness was assessed using both a strict definition (one correct option) and an expanded definition (accepting "allow" or "recommend" when supported by evidence). A total of 136 respondents met the inclusion criteria and provided paired responses. Median accuracy was found to be 52% (95% CI 48-55) under the strict definition and 70% (95% CI 67-72) under the expanded definition, with no significant differences observed between neoadjuvant and adjuvant settings. Evidence-based therapies, such as physical exercise and cognitive behavioral therapy, were most frequently recommended, whereas most other therapies received endorsement from fewer than 25% of respondents. Overall, oncologists exhibited moderate alignment with evidence, demonstrating a tendency to permit rather than actively recommend complementary therapies, even when evidence indicated potential benefits and safety. These findings underscore the necessity for targeted educational interventions aimed at enhancing oncologists' understanding and ensuring the safe and informed integration of complementary therapies into clinical practice.

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