Multilocular thymic cyst with epithelioid granulomata of unknown etiology: a radiologic and histopathologic correlation

Multilocular Thymic Cyst in a Young, Otherwise Healthy Woman: A Case Report

Thymic cysts are rare lesions, accounting approximately for 1% of all mediastinal masses. We report a case of a 36-year old woman who presented preoperatively with a calcified mass shadow found on a routine chest radiograph X-ray. After further investigation with chest computed tomography (CT), magnetic resonance imaging (MRI), and tests for Myasthenia gravis, a benign mediastinal cyst was diagnosed and the patient underwent median sternotomy and complete surgical excision of the lesion. The histological examination described a multilocular thymic cyst. Thymic cysts are usually associated with thymic epithelial tumors, such as thymomas, or multisystemic morbid conditions such as human immunodeficiency virus (HIV) infection, rheumatologic disease, and Myasthenia gravis. At all follow-up examinations to date, the patient remains healthy.

A Rare Case of Multilocular Thymic Cyst with Follicular Lymphoid Hyperplasia: Radiologic and Histopathologic Features

Multilocular thymic cysts are rare and acquired lesions induced by an inflammatory arising within the thymus. We report a rare case of multilocular thymic cyst with follicular lymphoid hyperplasia in a 59-year-old female. Chest CT and MRI revealed a large multilocular cystic mass, which contains thick septa and nodules in the thymus. F-18 FDG PET/CT showed almost no FDG uptake of the multilocular cystic mass but moderate FDG uptake of the solid nodules. Extended total thymectomy was performed. Histopathological findings revealed follicular lymphoid hyperplasia of thymic tissue but no neoplastic lesion. Based on these findings, diagnosis of multilocular thymic cyst with follicular lymphoid hyperplasia was made. This is a rare case that preoperatively was difficult to diagnose.

Rare case of a large mediastinal cyst involved in Hodgkin's lymphoma

We report a case of a mediastinal cystic retrosternal process, discovered by magnetic resonance imaging (MRI) in a 19-year-old male patient, with unusual inhomogenous signals in both T1- and T2-weighted images and contrast-enhancing septation. Macroscopically, the tumor weighed 1330 g, and was constituted by one dominating cyst measuring 14 cm in diameter. Additional small cysts were seen microscopically. The cystic wall was continuously infiltrated by nodular sclerosing Hodgkin's lymphoma, also affecting adjacent lymph-nodes. Age and sex of the patient and the diagnosed subtype of Hodgkin's lymphoma are in line with previously reported rare cases of mediastinal cysts with Hodgkin's lymphoma. The cyst reported here, most likely a secondary thymic cyst, is larger than those reported before. The main reason for the development of these cysts might be the accompanying inflammation of the lymphoma. Little is known about the imaging features of mediastinal cysts caused by lymphoma. Plain thymic cysts are normally homogenous on T1- and T2-weighted images. Hodgkin's lymphoma might be homogenous on T1-weighted images and is mostly inhomogenous on T2-weighted images. In case of inhomogenous cysts with contrast-enhancing septation, one should consider the diagnosis of an associated neoplasm.