Breast Cancer Treatment Requires More Than Just Medication
Higher Intramuscular Fat Leads to Lower Breast Cancer Treatment Efficacy
A research team at Yonsei Cancer Center has found that the level of intramuscular fat accumulation can impact the effectiveness of breast cancer treatment. Their study revealed that patients with a higher proportion of intramuscular fat tend to exhibit a lower response to breast cancer therapy.
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The study was conducted by Professor Hyun Wook Kim and Professor Min Hwan Kim from the Department of Oncology at Yonsei Cancer Center, Professor Namki Hong from the Department of Endocrinology at Severance Hospital, and Researcher Su Kyung Han from the Research Support Division at Yonsei University College of Medicine. Their findings were recently published in the latest issue of the Journal of Cachexia, Sarcopenia and Muscle.
The research team built upon previous studies indicating that metabolic dysfunction negatively affects the response to hormone receptor-positive breast cancer treatment. They specifically analyzed the impact of myosteatosis (excess fat accumulation in the muscles) on the efficacy of breast cancer therapies, particularly CDK4/6 inhibitors combined with aromatase inhibitors.
The study examined 247 patients with hormone receptor-positive breast cancer who received treatment at Yonsei Cancer Center. Using abdominal CT scans, the researchers measured intramuscular fat levels in the third lumbar vertebra (L3) region before treatment and assessed treatment outcomes.
Results showed that among the 83 patients with myosteatosis, the risk of disease progression increased by 84% compared to those without myosteatosis. The impact was particularly pronounced in younger, premenopausal patients and those without lung or liver metastases. The researchers suggested that metabolic dysfunction associated with myosteatosis may contribute to treatment resistance in premenopausal patients. Furthermore, they noted that even in patients without visceral organ metastases, those with myosteatosis exhibited outcomes as poor as those with metastases.
Professor Hyun Wook Kim stated, “We have confirmed that low muscle radiodensity, indicative of myosteatosis, is a crucial factor in predicting the effectiveness of breast cancer treatments. Beyond drug therapies, improving muscle quality through proper nutrition and exercise should be considered essential in breast cancer management.”
Editor 메디마스터
Provided by: YONSEI UNIVERSITY