Need for organ preservation in postchemotherapy retroperitoneal lymph node dissection (PC-RPLND).

Abstract

5031 Background: The aim ofPC-RPLND for advanced nonseminomatous germ cell tumors is to resect all remaining metastatic tissue. So far, the resection of adjacent visceral or vascular organs is also commonly performed to achieve complete resection of the residual mass. To determine the possibility of more organ preservation, we aimed to analyze the pathohistology of patients with adjunctive surgery as the frequency of metastatic involvement in those organs with teratoma or vital cancer is currently unknown. Methods: We reviewed a cohort of 1204 patients who underwent PC-RPLND between 2008 and 2021 as a 2-center study and identified 242 (20.1%) cases of adjunctive surgery during PC-RPLND. We analysed the pathohistological presence of germ cell tumor elements in the resected organs: viable tumor (V), teratoma (T) or necrosis / fibrosis (N). Surgery associated complications were reported according to the Clavien-Dindo classification. Outcomes of subgroups were compared by using log-rank test. Results: V, T and N were present in 54 (22%), 94 (39%) and 94 (39%) of all patients with adjunct resected organs. In 242 patients, 325 adjunct organs were resected with 66 (27.3%) of these patients receiving a resection of multiple organs. The kidney was the most often resected organ (n = 77; V: 29% T: 39% N: 32%), followed by V. Cava (n = 67; V: 25% T: 36%, N: 39%) and partial liver resections (n = 50; V: 16%, T: 30%, N: 54%). Postoperative complications occurred in 30% of which 22% were Clavien grade III-V, showing no significant differences between V, T and N; p = 0.093. 27% of all patients suffered from a relapse during a median follow-up of 22 months [0-180]. Patients with T or V in the resected specimens had a significantly reduced 5-year RFS compared to patients with only N (39%, 81%, p < 0.001). Conclusions: This study shows tremendous need for more organ preservation as 40% of all resections of adjunct organs are oncologically unnecessary due to the presence of N only in the pathological specimens. Therefore, in case of doubt, we should increase intraoperative frozen section to avoid oncologically unnecessary adjunctive surgeries, especially nephrectomies and vascular resections. Additionally, serological or image-based means for a more accurate presurgical workup are required to spare patients with N from PC-RPLND in general.