Clinicopathological study of mediastinal lesions with immunohistochemical study

Introduction: Mediastinum is the central portion of the thoracic cavity, compartmentalization of which into anterior, middle, and posterior compartments is useful in understanding the vast diversity of pathological lesions in this space. Cysts, inflammatory lesions, various primary, and metastatic tumors are found in this region, which tend to have a predilection for specific area of mediastinum depending on histopathological type. Objective: The objective was to study the clinicoradiological features and histopathological findings in patients presenting with mediastinal masses in a tertiary care hospital over a period of 10 years. Materials and Methods: This is a retrospective cross-sectional study of cases presenting as mediastinal lesions. Detailed clinical history and radiological findings were noted wherever available. Histopathology and immunohistochemical slides were reviewed. The data were analyzed using mean and percentage. Results: Twenty-four cases of mediastinal lesions were found in this study. It included 4 nonneoplastic lesions, 12 benign, and 8 malignant neoplastic cases. The age ranged from 3 months to 79 years. About 18 cases (64%) were located in the anterior mediastinum, and thymoma (8/18) was the most common lesion. One case each of pericardial cyst, bronchial cyst, and Hodgkin's lymphoma were seen in the middle mediastinum. Three cases of schwannoma and one case of neuroendocrine carcinoma were seen in the posterior mediastinum. Pan-cytokeratin, lymphoma panel, neuroendocrine markers, and placental alkaline phosphatase were done in neoplastic lesions to confirm the diagnosis. Conclusion: This study reflects the varied mediastinal lesions and importance of triad of clinical, radiological, and meticulous immunohistopathological examination for arriving at an appropriate diagnosis.