Intrathyroidal Multiloculated Proliferating Thymic Cyst

Abstract

Ectopic thymic tissue in neck is not uncommon; however, ectopic thymic cysts in neck are rare and intrathyroidal thymic cyst is still rarer. Multilocular proliferating thymic cyst is a rare entity and very few cases are described in mediastinum. We present the first case of a 73-year-old male with an intrathyroidal multilocular proliferating thymic cyst mimicking thyroid malignancy radiologically.

Multilocular Thymic Cyst With Mucinous Differentiation: A Mimicker of Thymic Mucoepidermoid Carcinoma

“…1 Occasionally, these lesions can appear in the neck associated with the thyroid gland. 2 Histologically, acquired lesions of multilocular thymic cysts (MTCs) display cystic spaces of varying sizes lined by squamous or squamoid epithelium with occasional Hassall's corpuscle-derived nodular hyperplastic squamous areas that often show acute inflammation and cholesterol clefts. 1 While columnar epithelium might be present in other foci of the cyst, descriptions of purely mucinous epithelium occurring in these cysts are not found in the literature.…”

Mutiloculated thymic cyst: unusual presentation of mediastinal mass

“…Multilocular thymic cysts are rare and few cases are described in the mediastinum. 1 Mediastinal cyst constitutes 10-15% of all radio graphically detected mediastinal masses, and thymic cysts account for nearly 5% of all mediastinal masses. 2 Congenital cysts arise from remnants of thymic duct during the descent of thymic primordial down to the mediastinum and are thin walled with no evidence of inflammation.…”