What we commonly refer to as kidney cancer actually includes two aspects. One is renal cell carcinoma, and the other is renal pelvis cancer or ureteral cancer. The characteristics of hematuria are different in these two types. Renal cell carcinoma, simply understood, grows inside the kidney and is not connected with urine. Only when the kidney tumor grows large enough to breach the kidney or renal pelvis will the tumor rupture and bleed, causing hematuria. This generally occurs in the middle to late stages of kidney cancer. On the other hand, renal pelvis cancer or ureteral cancer exhibits intermittent hematuria in the early stages without significant symptoms, but as it progresses to the middle and late stages, symptoms like kidney hydronephrosis and hematuria slowly appear. When diagnosing these conditions, any occurrence of hematuria must be investigated to determine the cause. Initial screening can be done using urinary system ultrasound, urinalysis, or routine urine tests. More precise methods include enhanced CT or MRI of the urinary system, which facilitate easier diagnosis.