How to detect kidney cancer in early stage? Early stage kidney cancer can reach the level of cure after surgery, so early detection of kidney cancer is the key. Due to the above clinical characteristics of kidney cancer, it is generally not easy to detect, how to detect kidney cancer in early stage? Ultrasound is the most non-invasive, direct and easy to detect lesions, and it can detect lesions as small as 0.5cm. CT or MRI must be performed to clarify the diagnosis after ultrasound detects a kidney mass, and CT or MRI is needed to identify a few benign tumors. Puncture biopsy is generally not recommended for kidney tumors because it is prone to false negatives and may lead to peri-tumor implantation, except for advanced kidney cancer that is inoperable and requires a clear diagnosis before puncture biopsy is considered.