Renal cell carcinoma (RCC) is one of the common malignant tumors of the urinary system, with an incidence rate of 2%-3%. With the development of imaging, the detection rate of renal cancer has been increasing. A small number of patients with large renal tumor or invasion to renal pelvis will show symptoms such as lumbar pain, abdominal mass, hematuria, etc. However, most patients with renal tumor do not have obvious symptoms in early stage, so the diagnosis of most early tumors mainly relies on imaging examinations: for example, conventional ultrasound can detect lesions of more than 1cm, but ultrasound does not have a good tendency to diagnose benign and malignant, except for the diagnosis of malignant tumor. diagnosis. Therefore, during daily physical examination, if ultrasound suggests neoplasm or occupancy in the kidney, further enhanced CT or MRI should be performed, because malignant renal tumor is rich in blood supply and will have enhanced changes when enhanced contrast is injected, which is good for differentiating benign and malignant renal tumors. Recently, with the development of ultrasonography, it is no longer a problem to distinguish renal cyst and cystic kidney cancer in clinical practice. Because imaging examination only has a diagnostic tendency, and 5%-10% of kidney tumors are difficult to identify the nature by imaging. Therefore, the final diagnosis of tumor still needs to rely on pathological diagnosis, which is the most reliable basis for biopsy results after kidney tumor removal. After kidney tumor is found by some methods mentioned above, most patients will choose surgery. However, a small number of patients will continue to observe and wait for a period of time (for tumors that tend to be benign in imaging diagnosis, such as malignant tumors, active follow-up and observation is not a bad way to go).