Biology of renal cancer tumor thrombus - towards the personalized approach

Renal cell carcinoma - related thrombus arising within venous system (venous tumor thrombus, VTT) represents a distinct compartment within cancer, situated at the frontline with the continual interaction with host blood cells. Various host immune blood cells may possibly interact with VTT influencing its biology. While many authors have reviewed the current state-of-the-art of the management of VTT, its biology and microenvironment has not been comprehensively reviewed to date. In this narrative review, we described the current concepts on formation of thrombus, its histopathology, immune microenvironment, genetic and molecular features with potential impact on prognostication and tailored therapy. Although it is the sophisticated and challenging surgery that remains the primary modality in the management of RCC with VTT, recent advances in the research on cancer biology and microenvironment shed some light on the numerous future perspectives. The formation of tumor thrombus is a complex process, understanding of which may trigger onset of novel therapies leading to the improvement of not only oncological results but also patients' safety in these life-threatening conditions.