Association of skeletal muscle quantity and quality with mortality in women with nonmetastatic breast cancer.

Abstract

Women with breast cancer are predisposed to muscle mass loss, to compromised muscle quality, and to decreased strength, and these abnormalities may serve as important predictors of adverse outcomes, including mortality. The aim of this study was to evaluate the possible associations between muscle mass markers, assessed by computed tomography with the phase angle (PhA) obtained by Bioelectrical impedance analysis (BIA), and health outcomes in women with breast cancer.

Methods: retrospective study with 54 women newly diagnosed with breast cancer, aged ≥ 18 years and < 65 years; histologically confirmed diagnosis of early breast cancer (stage I-III range), and in the first chemotherapy-cycled treatment. Measurements performed: anthropometric assessments, BIA, third lumbar vertebra by computed tomography (CT) and physical function (handgrip strength, gait speed test 4 m, fatigue assessment), and blood biochemical analysis.

Results: Lower skeletal muscle index were correlated with reduced PhA values (R² = 0.222, p = 0.0047), suggesting a worse prognosis. Logistic regression analysis showed that individuals with low muscle mass had a significantly lower likelihood of survival compared to those with normal muscle mass regardless of age and cancer stage.

Conclusion: low muscle mass negatively affected patient survival and was associated with lower PhA values. Phase angle emerges as a promising marker of overall health and could be a valuable clinical tool in assessing prognosis.