Thoracic Kidney

A 74-year-old man with diabetes and hypertension was referred to the hospital for evaluation of a mass in the right side of the chest, identified on a radiograph (Panel A, arrows). He reported no pulmonary problems and no history of chest trauma. Physical examination was unremarkable. Reformatted coronal (Panel B) and sagittal (Panel C) computed tomographic scans show the right kidney (large arrows) and part of the liver protruding above the diaphragm (small arrows) and into the posteromedial aspect of the right hemithorax through the foramen of Bochdalek (arrowheads indicate the defective fusion of the diaphragm).

Thoracic kidney is a rare congenital anomaly. Because of the location of the liver, thoracic kidney on the right side is much less common than thoracic kidney on the left side. Thoracic kidney is twice as common in men as in women. Typically, the presence of a thoracic kidney is asymptomatic and requires no intervention, as in this case.