18F-FDG PET/CT Findings of Isolated Renal Metastasis From Squamous Cell Lung Cancer

We present the 18 F-FDG PET/CT findings of a 64-year-old man with isolated renal metastasis. He had a history of radical surgery for squamous cell lung cancer 14 months ago, followed by chemotherapy and immunotherapy. The renal metastasis presented as a small focus of increased FDG uptake in the restaging 18 F-FDG PET/CT scan, which was regarded as renal cortical tracer retention. The renal metastasis was more prominent on the second PET/CT performed 5 months later. The patient subsequently underwent radical nephrectomy, and histopathological examination confirmed the diagnosis of renal squamous cell carcinoma metastasis.