Extended Summary Objective To analyse the outcomes of retroperitoneoscopic upper and lower moiety hemi-nephroureterectomy (HNU) and to assess the different variables that may have an impact on outcome; remnant moiety damage, morbidity and the need for secondary surgery. Methods Prospectively recorded data of retroperitoneoscopic HNU’s performed by a single surgeon from 2005-2018 were analysed. Patients were split into 2 groups according to moiety affected (UMHNU and LMHNU).
