229 Background: PC-RPLND remains an integral part of the multimodality treatment for advanced NSGCT. The need to resect and to replace the major retroperitoneal vessels must be known preoperatively to enable complete resection of the residual masses. Methods: PC-RPLND was performed in 411 patients with NSGCT and normalized (81%) or plateauing (19%) tumor markers following 3-4 cycles PEB/PEI. PC-RPLND was performed in 5 institutions with a variable surgical frequency of 14 to 158 PC-RPLNDs. Good, intermediate, and poor prognosis according to the IGCCCG criteria was identified in in 59.8%, 21.2%, and 19% respectively. Results: Resection of the inferior vena cava was performed in 28 (6.81%), resection of the abdominal aorta was necessary in 13 (3.16%) patients. In 29/41 (70.7%) adjunctive surgical procedures such as nephrectomy, small bowel resection, ureteral resection had to be performed to ensure complete resection of the residual masses. Histologically vital cancer or mature teratoma was identified in 78.1% of the resected vascular specimens. Mean time of surgery was 295 (243-615) Min., mean blood loss was 690 (350 – 3400) ml. Good prognosis was identified in 15.4%, intermediate and poor prognosis was present in 41%and 43.6%, resp. Of all 411 patients involvement of the major retroperitoneal vessels was found in 3.2%, 18.4% and 21.8% with good, intermediate, and poor prognosis, resp. The mean tumor diameter was 5.9 (1.0 – 32) cm for the entire cohort and 9.8 (4-32) cm for the cohort of patients with vascular surgery. Significant prognosticators to predict vascular involvement were identified by multivariate analysis: intermediate/poor prognosis, number of cycles of chemotherapy, tumor diameter > 14cm, circumferential encasement of > 50% of the vessel diameter. Conclusions: Complete resection of the inferior vena cava or the abdominal aorta during PC-RPLND is necessary in about 10% of patients. The identified predictors enable already preoperatively a risk adapted interdisciplinary approach for complete resection of the residual masses in an experienced centre. No significant financial relationships to disclose.