Ovarian sex cord tumor with annular tubules in a patient with Turner syndrome.

A case of ovarian sex cord tumor with annular tubules (SCTAT) in a 24-year old woman with Turner syndrome is presented. Close association of dysgenetic gonads and gonadoblastoma has been clearly documented, and there have been sporadic reports of patients with other gonadal tumors. To our knowledge, a case of SCTAT in a patient with 45,X/46,XX Turner syndrome has not been reported. On the basis of histopathologic, immunohistochemical, and ultrastructural findings, we suggest that the SCTAT originated from pluripotential stem cells of the gonads and differentiated into either granulosa cells or Sertoli cells. We postulate a possible relationship between the SCTAT and gonadoblastoma based on the morphologic resemblance and occurrence in dysgenetic gonads.