Primary adenocarcinoma of the rete testis with elevation of serum carcinoembryonic antigen: a case report

Primary adenocarcinoma of the rete testis, which arises from the collecting systems of the testis, is an extremely rare tumor with a poor prognosis. A case of primary adenocarcinoma of the rete testis with elevation of serum carcinoembryonic antigen (CEA) levels is reported. A 59-year-old man presented with left scrotal swelling. Ultrasonography showed a left hydrocele and swelling of the left testis with calcification. Computed tomography showed para-aortic lymph node swelling and multiple lung metastases. Germ cell tumor markers were within the normal range. Radical orchiectomy was performed, and histological examination showed adenocarcinoma. The tumor cells were immunohistochemically positive for CEA. There was no evidence of other primary carcinomas. The tumor was finally diagnosed as a primary adenocarcinoma of the rete testis. The patient had bone metastases 8 months after orchiectomy with increased serum CEA levels. CEA might be a marker for primary adenocarcinoma of the rete testis.