Among mediastinal tumors requiring operative treatment endothoracic goiters have to be considered as common cause (13.7%) in differential diagnostic aspects next to dysontogenetic and neurogenic tumors. Final diagnosis is best established by chest x-rays in two directions, perhaps with additional barium swallow and a scintigraphy (131I or technetium). Angiography is of no valuable further information concerning tumor identification or operability. The disadvantage refers to unwanted iodine load in case of thyroid malignancy. The operative approach for real mediastinal goiter necessitates partial or total sternotomy or occasionally lateral thoracotomy.