Elevated serum erythropoietin as a marker of renal cell carcinoma in a hemodialysis patient

Abstract

We report a hemodialysis (HD) patient with elevated serum erythropoietin (EPO) as a tumor marker of renal cell carcinoma (RCC).
The case was a 50-year-old male, who had been on hemodialysis for 14 years.
He was incidentally diagnosed as having a left renal tumor with acquired cystic disease of the kidneys by computed tomographic scanning. He presented an elevation of hematocrit (Ht) up to 33% with unexpected erythrocytosis despite no EPO supplementation. His serum EPO level was inappropriately high, at 57.8mU/ml.
The EPO level concomitantly increased to 122mU/ml with enlargement of the left renal tumor at 7 months. At this time, he underwent left radical nephrectomy for the renal tumor. The pathological definitive diagnosis of RCC was confirmed. Postoperatively, his EPO level decreased markedly to 15.7mU/ml.
We propose that an inappropriate EPO level is a potentially useful tumor marker of renal cell carcinoma with acquired cystic disease of the kidneys in dialysis patients.