**Acknowledgements**

Finally, although RCC invades the venous system to form tumor thrombus, the tissue components between the primary tumor of the kidney and the tumor thrombus has a large difference. Meanwhile, heterogeneity exists in primary RCC and tumor thrombus, which may be the reason why primary tumor and tumor thrombus response to preoperative targeted therapy was asynchronous, and drugs among different patients respond differently. Therefore, the research of heterogeneity between primary RCC and venous tumor thrombus may find a more effective therapeutic target and drug for the reduction of tumor thrombus level, which can provide the basis for selecting appropriate patients for neoadjuvant targeted therapy

Open IVCTE is still a standard surgery for RCC with IVC thrombus. With the development of laparoscopy and robotic technology in recent years, the safety and feasibility of robotassisted laparoscopic IVC thrombectomy have been investigated at several centers. Those successful experiences mark that such surgery tends to enter the era of mini-traumatic surgery. Considering the complexity of the patient and the high complication rates, multidisciplinary cooperation and detailed preoperative assessment will play an important role in surgical decisions in future. Some new or mature techniques will also provide a basis for the surgical strategies, including artificial blood vessel, augmented reality, transesophageal echocardiography, IVC venography, and so on. From a safety perspective, IVCTE is still a challenging technology. Only a hospital with skilled laparoscopic and mature surgical team is recommended. Preoperative TMT is expected to shrink the IVC thrombus and reduce the complexity of the surgery. However, prospective investigations are required in

RCC tends to invade the venous system and form venous tumor thrombus in 4–10% of patients. Surgical treatment is the standard therapy for these patients; however, postoperative complications include hemorrhage, thrombotic shedding, and other risks. Because of the huge population and relatively backward treatment concepts, the proportion and number of patients with advanced RCC in China are significantly higher than those in developed countries, such as Europe and the United States. With regard to patients with RCC and tumor thrombus, the strategies for diagnosis and treatment are mostly based on open surgery. Several clinic-related strategies are no longer suitable for current laparoscopic and robot-assisted mini-traumatic surgeries owing to the development of surgical techniques and improvement of auxiliary equipment. With regard to the tumor thrombus, a series of retrospective and prospective studies are needed to be conducted, which would enable to solve some difficulties and issues in the course of diagnosis and treatment, to improve the clinical strategies of diagnosis and treatment of patients with RCC and tumor thrombus ulteriorly,

and to provide our clinical work with more powerful reference and basis.

preoperatively.

206 Evolving Trends in Kidney Cancer

the future.

**11. Conclusions**

**10. Future perspectives**

This work was supported by the People's Republic of China and the National High Technology Research and Development Program ("863" Program) of China: the screening and clinical validation of characteristic protein biomarkers in renal cancer based on a large-scale biobank (2014AA020607).
