Sarcopenia (including normal-weight obesity), its impact on prognosis and treatment outcomes in patients with breast cancer: a systematic review

Abstract

This article presents a systematic review on the impact of sarcopenia, including normal-weight obesity, on the prognosis and treatment outcomes in breast cancer patients. The research highlights that body composition, rather than just Body Mass Index (BMI), is a crucial prognostic factor. Sarcopenia, characterized by the loss of skeletal muscle mass, and sarcopenic obesity, which combines low muscle mass with excess adiposity, are conditions that significantly affect therapeutic outcomes. This review, conducted according to PRISMA guidelines, analyzed five articles selected from the 18 initially identified, published between 2012 and 2026. The findings indicate that sarcopenia is associated with a significantly increased overall mortality in breast cancer survivors, even in individuals with normal or elevated BMI. Sarcopenic obesity, frequently observed in normal-weight patients, is linked to reduced survival, poorer quality of life, and a higher risk of unexpected toxicity during chemotherapy, especially with taxanes, due to muscle attenuation. The study emphasizes the importance of early identification of patients with normal-weight obesity to mitigate treatment-related toxicity. Furthermore, resistance training is highlighted as an effective non-pharmacological intervention to preserve muscle integrity and improve clinical outcomes. The incorporation of imaging-based body composition assessment into routine oncology practice is recommended for a more precise and individualized treatment approach.