Congenital Thymic Cyst in the Retro Cava Position: A Case Report

Introduction: Congenital thymic cyst (CTC) is a rare mediastinal mass and the retrocaval position of this cyst has not been reported in the medical literature so far. Case Presentation: The present study reports on a 66-year-old female with coronary artery disease (CAD) who was scheduled for coronary artery bypass grafting (CABG) at our hospital. During mediastinal exploration and pericardiotomy for CABG, a large CTC was incidentally found in the retrocaval position, as a watery cyst from its anatomic location and content. Pathological examination revealed that it was a CTC. No cases of retrocaval position of CTC have been reported. Thus, here we report on this case and review the previously reported cases. Conclusions: To our knowledge, this is the first case of CTC that was identified incidentally in the retrocaval position and caused intermittent obstruction of vena cava.