Caren van Roekel

183 Dose-effect relationships of holmium-166 radioembolization in colorectal cancer Conclusion A significant dose-response relationship in CRC patients treated with 166 Ho- radioembolization was established and a positive association between toxicity and parenchymal dose was found. For future patients, it is advocated to use 166 Ho-scout to select patients and personalize the administered activity targeting a mean tumor-absorbed dose of >90 Gy and a parenchymal dose <55 Gy. Key words : radioembolization, holmium, dosimetry 7