A randomized controlled trial assessing the release of circulating tumor and mesenchymal cells in no-touch radical nephrectomy

Introduction & Objectives: Circulating tumor cells (CTCs) can be the missing renal cell carcinoma (RCC) biomarker. All Robson principles of radical nephrectomy (RN) were rebutted, except for early pedicle ligation. A no‐touch (NT) resection showed benefits in other cancers. The objective of this study is to determine if NT RN reduces CTC or circulating mesenchymal cell (CMC) release. Materials & Methods: Randomized controlled trial comparing CTC and circulating mesenchymal cell (CMC) release in no‐touch (NT) vs. conventional (C) laparoscopic RN. Blood samples were collected at operation room arrival (S0), specimen extraction (S1), postoperative D1, and D30. CTCs isolated and analyzed using the RUBYchip™. Results: From September 2021 to April 2022, 34 patients were randomized. There was no significant difference between intervention groups in CTC and CMC variations between time points. Complication rates were similar. CTC detection rates (DR) were 0%, and 6.25% at both S0 and S1, 18.75% and 12.5% at D1, and 6.25% and 12.5% for D30, respectively for NT and C groups. CMC DRs were 68.9%, and 75.0% at S0, 50.0%, and 81.25% at S1, 37.5%, and 56.25% at D1, and 50.0%, and 43.75% at D30, respectively for NT, and C groups. There was a progressive decrease in CMCs after surgery in the C group, mainly at D1, from 4.78 to 1.64 CMCs/7.5mL of blood (p=0.035). Healthy controls showed no circulating cells. However, high CMC counts were found in chronic inflammation controls and oncocytoma patients, similar to RCC patients (p=0.460). Main limitations were a small sample size and no downstream cell analysis. Conclusions: NT RN did not reduce circulating cell release nor improved survival compared to the C RN.