Unilocular and multilocular thymic cysts: A study on the possible histomorphological and/or clinical differences

Abstract

Objective: Thymic cysts are rare mediastinal cystic pathologies and have two subtypes namely unilocular and multilocular. This study aims to investigate the clinicopathological characteristics of thymic cysts and to compare the clinical and histopathologic features of multilocular thymic cysts (MTCs) and unilocular thymic cysts (UTCs). Patients and Methods: Twenty-three patients with the diagnosis of thymic cyst between 2012 and 2020 were included. We compared the clinicopathological characteristics of unilocular and multilocular thymic cysts. Results: The mean age of patients was 43 years, ranging from 6 to 80 years. Fourteen cases were UTCs and 9 cases were MTCs. MTCs were found to be statistically more common in younger patients, and have much more histomorphological changes pointing to the complicated cysts (p<0.05). Moreover, we noted that patients with MTCs were found to be more symptomatic before diagnosis. Furthermore, in our study when we compared MTCs and UTCs, UTCs were slightly (64.2%) more frequent in female patients. Conclusion: According to our results, thymic cysts may also be seen at younger ages. MTC and UTC can have different histomorphological characteristics, such as in foreign body reaction and hemorrhage. Moreover, there can be different clinical features, such as age, gender, and symptoms, between these two subtypes.

Keywords

• Thymus
• Cyst
• Multilocular
• Unilocular
• Pathology
• Histomorphology

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