Left renal tumor discovered 6 months ago. Medical history: male, 67 years old. The patient discovered a left renal tumor about 4 cm in diameter during a physical examination 6 months ago (no report available), and the patient did not take any special measures. Three weeks ago, the patient had a re-examination at another hospital, and an ultrasound revealed a heterogeneous hypoechoic area in the lower pole of the left kidney, measuring approximately 86 mm × 68 mm × 65 mm. Further enhanced CT showed a mixed density mass in the lower pole of the left kidney with unclear boundaries. The enhanced scan showed obvious uneven enhancement, with the larger cross-sectional size about 97 mm × 66 mm. Multiple enlarged lymph nodes were seen in the retroperitoneal space, the larger one measuring about 13 mm × 11 mm. Both kidneys showed round low-density non-enhancing shadows (Fig. 1a, b). PET/CT showed increased FDG metabolism in the left renal mass, multiple nodular FDG metabolism in both lungs, and multiple nodular FDG metabolism in the liver. Considering the medical history, it is highly suspected of left renal carcinoma with multiple metastases. The patient occasionally has back pain but no hematuria, frequent urination, urgency, abdominal pain, or bloating.