Towards an understanding of the role of soft tissue structural and mechanical properties in upper limb function after breast cancer treatment: the SOFT-TI-TRIAL

Upper limb (UL) dysfunctions after breast cancer treatment are complex and multifactorial. Increasing proof of concept is available for local soft tissues problems as underlying mechanism of UL dysfunctions during and after breast cancer treatment. These problems include structural changes (tissue composition, thickness and volume) and altered mechanical properties (tissue stiffness and impaired gliding). The challenge is to properly assess these properties to get a true understanding of their contribution to UL dysfunctions. Up to know, only (subjective) methods with limited validity were used. Also, longitudinal assessments of all properties together are lacking. Therefore, a comprehensive set of innovative, high-quality and objective ultrasound techniques for assessment of both structural and mechanical properties will be developed and adopted. More specific, the research objectives are 1) developing and testing a comprehensive assessment protocol for the quantification (i.e. severity) of soft tissue properties with ultrasound techniques; 2) exploring the clinical relevance of ultrasound findings by comparing them with other clinical outcomes and 3) determining the value of soft tissue properties (evaluated with ultrasound) as a diagnostic and prognostic biomarker for UL dysfunctions up to one year post-breast cancer surgery. With these insights, tailoring currently available and/or new therapies to the exact underlying mechanism(s) of UL dysfunctions will improve.