- Week 26: third visit. Patients will be invited to come to the Luxembourg Institute of Health (Strassen, Luxembourg). During this third visit (duration: 70 min), patient will fill in the EORTC-QLQ30 questionnaire and the cost questionnaire. Height and weight will be measured. Patients will perform the same physical fitness tests as during the first and second visits (ramped Bruce protocol on a treadmill, leg strength and grip strength). Patients will be handed out the accelerometer to be worn during one week to evaluate their physical activity behaviour.