Abstract
We report a case of alpha-fetoprotein (AFP) producing renal cell carcinoma. A
53-year-old man with fever was found to have a left renal mass on computed
tomography. No mass was detected in the liver. Serum AFP was 1,460 ng/ml.
Radical nephrectomy showed a 10 cm mass in the upper half. A half of the tumor
was whitish yellow and firm whereas another half was soft and bright yellow with
hemorrhagic and necrotic areas. Histologically, the two areas were different.
The lower part consisted of the clear cell renal cell carcinoma and the upper
part consisted of granular cells. On immunohistochemistry, the granular tumor
cells only were positive for AFP. Serum AFP level dropped abruptly to 383 ng/ml
on the 6th postoperative day and gradually returned to normal during the 6
months. Multiple metastatic nodules were found in the lungs, liver and bone in
9th postoperative month and the AFP was less than 1 ng/ml. This suggest
metastatic lesions are non-AFP producing clear cell type. It can be concluded
that serum AFP elevation was due to synthesis by the renal cell carcinoma in the
absence of liver neoplasm. Although AFP producing renal cell carcinoma is a rare
entity, serum AFP can be a useful marker for the detection of the tumor.