OBJECTIVES: To prospectively assess contemporary complication rates of minimally-invasive staging pelvic lymph node dissection before curative radiotherapy for prostate cancer using a standardized classification. METHODS: A total of 100 prostate cancer patients underwent laparoscopic or robot-assisted pelvic lymph node dissection (95% extended). Surgical outcomes were compared with those of 43 patients undergoing open pelvic lymph node dissection (33% extended). Complications were recorded prospectively during hospitalization and follow-up visits, and graded using Clavien-Dindo classification. Lymphocele size was measured on postoperative magnetic resonance imaging or computed tomography. RESULTS: Of the complications recorded, 10% were grade 1, 3% were grade 2 and 6% were grade 3. No grade 4-5 complications occurred. Compared with open pelvic lymph node dissection, minimally-invasive pelvic lymph node dissection was associated with less blood loss (P = 0.001) and shorter hospital stay (median 3 vs 6 days; P < 0.001), but longer operation time (130 vs 98 min; P < 0.001). The complication rate was similar in both groups. For the entire cohort, overall and symptomatic lymphoceles were seen in 91 (64%) and 18 patients (13%), respectively. On multivariate logistic regression, minimally-invasive surgery was the only independent predictor for lymphocele development (odds ratio 3.99; P = 0.015). CONCLUSIONS: Minimally-invasive extended pelvic lymph node dissection before curative radiotherapy is associated with low morbidity. Asymptomatic lymphocele development rate is higher compared with open pelvic lymph node dissection.