Responsiveness of the New Index Muscular Echotexture in Women with Metastatic Breast Cancer: an Exercise Intervention Study

Ultrasound imaging texture analyses may provide information on tissue homogeneity changes in metastatic breast cancer (MBC) through second-order analyzes based on the gray-level co-occurrence matrix. This study aimed to analyze the responsiveness and correlations of biomarkers of muscular and fat echotexture after an exercise intervention in women with MBC. A 12-week exercise intervention was conducted in 2019, including aerobic and strength training. Echotexture variables were obtained at baseline and after intervention from the quadriceps (Q) and biceps brachii and brachialis. Mean differences were calculated using the T-Student parametric test for dependent samples of the differences in the means ( P = 0.05; 95% CI). Data obtained from 13 MBC women showed significant differences in some echotexture variables after the intervention. QLQ-BR23 questionnaire correlated with several echotexture variables from muscle and subcutaneous fat. PFS-R scale correlated positively with the Q Subcutaneous Fat Non-Contraction Homogeneity (R = 0.43, P < 0.05). Q Muscle Non-Contraction Energy and Q Muscle Non-Contraction Textural Correlation explained 90% of the variance of QLQ-BR23. Some muscle and subcutaneous fat echotexture biomarkers showed good responsiveness after the exercise intervention. Additionally, some muscle and subcutaneous fat variables correlated with QLQ-BR23 and cancer-related fatigue measured by PFS-R scale in MBC patients. Trial registration: NCT03879096