Measuring direct and indirect tendon parameters to characterize the proximal tendinous complex of the rectus femoris in football and futsal players.

Objective: To present unprecedented radiological parameters that characterize the angle between the direct and indirect tendons of the proximal rectus femoris (RF) and its inclinations and to evaluate the population variability according to demographic variables. Materials and methods: From September 2019 to July 2021, using MRI multiplanar reconstructions of the proximal thigh/hip, two blinded radiologists measured the direct and indirect tendon angle and the inclination of each tendon in different planes. The intra- and inter-observer agreements were assessed with Bland-Altman analysis and intraclass correlation coefficient (ICC). The correlations between radiological parameters and demographic variables were evaluated using linear regression, Student's t-test, and analysis of variance. Results: We performed 112 thigh/hip MRI scans on 91 football players of different age, gender, and disciplines (football and futsal). For observer 1 (the reference), the mean direct and indirect tendon angle was 56.74° ± 9.37, the mean indirect tendon slope was -7.90° ± 7.49, and the mean direct tendon slope was 22.16° ± 5.88. The three measurements showed inter- and intra-observer agreement (mean differences ∼0). No correlation was observed between age and the parameters. Likewise, no statistically significant differences were found for gender, dominant limb, examined limb, and sport. Conclusion: There is an inter- and intra-observer agreement in the measurements of the direct and indirect tendon angle and the inclination of each tendon. There is population variability in the proximal tendinous complex unrelated to demographic factors. These results allow further detection of morphological patterns that represent a risk factor for lesions in the RF in professional football and futsal players and other sports.

Concordance analysis between liquid biopsy (ctDNA) and tumor DNA molecular profiles from panel-based next-generation sequencing.

INTRODUCTION: Analysis of circulating tumor DNA (ctDNA), also known as liquid biopsy, has been postulated to be a useful test in the prognostication, molecular profiling, and monitoring of cancer patients. In this series we aimed to analyze the concordance between the mutation status of formalin-fixed paraffin-embedded (FFPE) tumor samples and matched ctDNA, considering tumor molecular profiling as the gold standard technique. METHODS: This retrospective study included cancer patients with complete diagnostics and gene mutations detected in a previous FFPE tumor tissue Next-Generation Sequencing (NGS) study with a matched frozen plasma sample available for an NGS ctDNA assay. RESULTS AND DISCUSSION: Sixty patients were included, 24 with colorectal carcinoma (CRC) and 36 with non-small cell lung cancer (NSCLC). In 27.1% of ctDNA studies a new mutation not previously detected in the matched tumor was found. 11.9% of these ctDNA results had the potential to impact clinical management. Globally, the concordance rate between FFPE tumor samples and ctDNA was 44.4%. When tumors were stratified by stage, the concordance was 76.5%, 70%, 36.4%, and 0% in tumor stages IV, III, II, and I, respectively. ctDNA molecular profiles showed a good concordance rate in advanced stage tumors and identified undetected mutations in tumor tissues. In early tumor stages the concordance was low, casting doubt on the usefulness of ctDNA in these patients.