Cheng-Pang Hou,1,2,* Wei-Chang Lee,1,2,* Yu-Hsiang Lin,1,2 Shao-Ming Chen,3 Chien-Lun Chen,1,2 Phei-Lang Chang,1,2,4 Horng-Heng Juang,4,5 Ke-Hung Tsui1,2,4 1Department of Urology, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, Republic of China; 2School of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, Republic of China; 3Hou-Pin Taipei Hospital, 4Bioinformation Center, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, Republic of China; 5Department of Anatomy, School of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, Republic of China *These authors contributed equally to this work Purpose: Patients with a high risk of prostate carcinoma typically have higher rates of positive surgical margins and biochemical failure following radical prostatectomy and adjuvant hormone therapy. In this study, we assessed the effects of neoadjuvant hormone therapy (NHT) on prostate carcinoma in high-risk patients following robotic-assisted radical prostatectomy (RARP). Methods: This retrospective study investigated the medical records of 28 patients who underwent RARP between January 2009 and October 2013. Twenty-two patients underwent NHT prior to RARP. Furthermore, six patients did not undergo NHT prior to RARP. Parameters including age, operating time, blood loss, blood transfusion status, and cancer stage were checked against anatomical correlations. Potential predictors of prolonged operating time and prolonged surgical procedures were assessed using multiple logistic regressions. Results: NHT was shown to be an independent predictor of prolonged total operating time. Tumor stage alterations did not appear to be associated with NHT followed by RARP. The patients who underwent NHT were not more likely to have positive surgical margins, and an increase in patients requiring blood transfusion was not seen. Conclusion: NHT appears to increase operative time during RARP. However, the perioperative morbidity of NHT patients undergoing RARP appears to be equivalent with that of non-NHT patients. Keywords: prostate carcinoma, robotic-assisted radical prostatectomy, surgical margin, operating time