[A case report of suspected Stauffer syndrome presenting with fever, extensive inflammation, and abnormal liver function tests].

A man was referred to our hospital because of malaise and abnormal liver function tests. He had had a kidney removed for early renal cell carcinoma. We performed ultrasonography, CT scan, and liver biopsy, all of which were normal. However, FDG-PET revealed abnormal, diffuse uptake in the bone. A bone biopsy showed abnormal clear cells resembling renal cell carcinoma. Because there was no other primary origin, this histopathological finding led to the diagnosis of bone metastasis of renal cell carcinoma, and the abnormal liver function test was thus inferred to be due to Stauffer syndrome.