Caren van Roekel

101 Quality of life in patients treated with 166 Ho-radioembolization social functioning were the most affected functioning scales. Role functioning is based on the patient’s ability to perform hobbies or other daily activities. Social functioning is measured to establish if one’s family life and social activities are influenced. Factors other than the treatment itself may influence these scores. Social functioning may for instance be affected by the instructions for radiation safety: all RE patients are instructed to keep a safe distance to family and relatives for the first days after treatment. In addition, participation in a clinical study with intensive monitoring and follow-up visits poses a significant time, psychological and physical burden, which may be reflected in decreased role- and social functioning. For the symptom scores, there was a rise in fatigue, pain, appetite loss, eating and contact with friends. The latter is coherent with social functioning. The prominent rise in the pain and fatigue symptom scores is in accordance with the well-known side effects of RE: clinical side effects usually occur within the first 4 to 6 weeks after treatment and may consist of abdominal pain, nausea, vomiting, fatigue and slight fever (3). In a subset of 26 patients, QoL assessment was added at 1 week post-treatment because it was thought this would better reflect the short-term adverse effects of the treatment. The steep decline in functioning scores and the rise of symptoms from baseline to 1 week is striking. This may be explained by the so- called post-embolization syndrome, which is known to occur after embolization therapies (3, 4, 37). Future interventional oncology studies are encouraged to evaluate QoL shortly after treatment (i.e. <2 weeks). Due to a large number of differences between the available studies on QoL in patients treated with 90 Y-RE and the HEPAR studies, such as the use of different questionnaires, different timing of the QoL evaluations and concomitant treatment with chemotherapy, it is impossible to make a fair comparison. Only 3 studies studied QoL in patients treated with RE as a monotherapy, whereas the others studied RE in combination or in comparison with other therapies. Moreover, in the HEPAR studies, all patients received a whole-liver approach in a single session. This is a more aggressive treatment approach of RE and may have influenced QoL. A higher number of 166 Ho- and 90 Y-resin microspheres (somewhere between 30-50 million) are typically injected for treatment in comparison with glass 3