Mediastinal Mature Teratoma Complicated with Complex Rupture into the Lung: A Case Report and Literature Review
Year: 2026
Type: preprint
Study design: Case Report
Abstract: Introduction: Mediastinal teratomas are the most common extragonadal germ cell tumors and are typically located in the anterior mediastinum. They are usually benign and asymptomatic. However, rupture into adjacent structures such as the lung or bronchial tree is an uncommon but clinically significant complication that may mimic malignancy or infection, leading to diagnostic challenges. Case presentation: We report a case managed at Abderrahman Mami University Hospital of a 38-year-old man presenting with a two-year history of chronic cough and recurrent hemoptysis. Thoracic computed tomography revealed a large heterogeneous anterior mediastinal mass containing fat, cystic, calcified, and soft tissue components, extending into the right upper lobe. The presence of intralesional air and surrounding inflammatory changes suggested rupture. Intraoperatively, a direct communication between the cystic lesion and the pulmonary parenchyma was identified, confirming rupture into the lung. Surgical resection was performed, requiring right upper lobectomy due to vascular and parenchymal involvement. Gross examination showed a cystic lesion containing sebaceous material and hair, extending into the lung tissue. Histopathological analysis confirmed a mature cystic teratoma composed of well-differentiated tissues derived from multiple germ layers, without evidence of immature or malignant components. Surgical margins were free of tumor, and the postoperative course was uneventful. Discussion: Rupture of mediastinal teratomas most frequently involves the lung or pleural cavity and presents with nonspecific respiratory symptoms such as hemoptysis, cough, or infection-like features. Imaging findings may be misleading, often simulating malignancy due to irregular borders, intralesional air, and inflammatory changes. In our case, rupture was confirmed intraoperatively by direct bronchopulmonary communication. A 20-year literature review identified nine similar cases, with pulmonary involvement representing the most common site of rupture. All reported cases were managed surgically, with favorable outcomes despite technical challenges related to inflammation and adhesions. Conclusion: Ruptured mature mediastinal teratomas represent a rare but important clinical entity. Their atypical presentation requires a high index of suspicion to avoid misdiagnosis and inappropriate management. Recognition of rupture, particularly when confirmed intraoperatively, is essential to guide appropriate surgical management and achieve optimal outcomes .
Source: Research Square
Institutions: Abderrahmane Mami Hospital, Tunis El Manar University
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7166559593