Techniques and outcomes of minimally-invasive surgery for nonmetastatic renal cell carcinoma with inferior vena cava thrombosis: a systematic review of the literature

INTRODUCTION: Current guidelines recommend considering surgical excision of non-metastatic renal cell carcinoma (RCC) with inferior vena cava (IVC) thrombosis in patients with acceptable performance status. Of note, several authors have pioneered specific techniques for laparoscopic and robotic management of renal cancer with level I-IV IVC thrombosis. EVIDENCE ACQUISITION: A systematic review of the English-language literature on surgical techniques and perioperative outcomes of minimally-invasive radical nephrectomy (RN) and IVC thrombectomy for nonmetastatic RCC was performed without time filters using the MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials and Web of Science (WoS) databases in September 2018 according to the PRISMA statement recommendations. EVIDENCE SYNTHESIS: Overall, 28 studies were selected for qualitative analysis (N.=13 on laparoscopic surgery, N.=15 on robotic surgery). The quality of evidence according to GRADE was low. Laparoscopic techniques included hand-assisted, hybrid and pure laparoscopic approaches. Most of these series included right-sided tumors with predominantly level I or II IVC thrombi. Similarly, most robotic series reported right-sided RCC with level I-II IVC thrombosis; yet, few authors extended the indication to level III thrombi and to left-sided RCC. Surgical techniques for minimallyinvasive IVC thrombectomy evolved over the years, with specific technical nuances aiming to tailor surgical strategy according to both tumor side and thrombus extent. Among the included studies, perioperative outcomes were promising. CONCLUSIONS: Minimally-invasive surgery is technically feasible and has been shown to achieve acceptable perioperative outcomes in selected patients with renal cancer and IVC thrombosis. The evidence is premature to draw conclusions on intermediate-long term oncologic outcomes. Robotic surgery allowed to extend surgical indications to more challenging cases with more extensive tumor thrombosis. Nonetheless, global experience on minimally-invasive IVC thrombectomy is limited to high-volume surgeons at high-volume Centers. Future research is needed to prove its noninferiority as compared to open surgery and to define its benefits and limits