Intrahepatic paratesticular cyst: unique presentation of vestigial remnants of Wolffian duct.

To report on a case of a progressively enlarging intrahepatic cyst in a 1-year-old boy who also presented with bilateral undescended testes. At surgery, the lesion emerged from the anterior surface of the liver but was unexpectedly found to arise from the epididymis of the right testis, which was located intra-abdominally. The histologic findings were consistent with a paratesticular cyst of vestigial remnants derived from the Wolffian duct. Such an unusual event has not been previously reported among the possible location of a paratesticular cyst, nor has it been described in the differential diagnosis of cystic lesions of the liver.