Huge Congenital Thymic Cyst with Microscopic Thymoma

The congenital thymic cysts are rare. They have a congenital origin and they are benign. The differential diagnosis of acquired cysts, cystic thymoma and thymic malignancies in cystic degeneration can be particularly difficult. Rarely, they assume clinical relevance for the appearance of symptoms of compression, more typical of malignant lesions, and the association with thymoma was reported in very few cases in literature. For all these features, treatment strategy remains controversial and in particular surgical approach. We report a case of a huge symptomatic congenital thymic cyst, surgically removed with histological finding of microscopic thymoma.