Microvascular skeletal muscle oxygenation and exercise capacity in childhood cancer survivors compared to healthy controls: a cross-sectional study

Abstract

The aim of the study was to evaluate skeletal muscle oxygenation and exercise capacity in childhood cancer survivors (CCS), and assess their association, in comparison with healthy controls. Twenty-six CCS (12 male, 6 months-10 yrs after treatment, mean age 17.59 (IQR:5.21 yrs) and 26 matched control subjects were recruited. Subjects performed a maximal incremental cardiopulmonary exercise test (CPET) on a treadmill with measurement of VO2peak (peak oxygen uptake). Simultaneously, muscle oxygenation was measured in the gastrocnemius muscle via Near InfraRed Spectroscopy. Changes (µM) in deoxyhemoglobin (ΔHHb), total hemoglobin (ΔtHb), and tissue saturation index (ΔTSI) were calculated as the differences between maximal (ΔHHb/ΔtHb) or minimal (ΔTSI) exercise test- and rest values. CCS had a significantly lower VO2peak (-12.05 ml/kg/min, p