A rare case report of an endobronchial teratoma of the right upper lobe invading the mediastinum.

INTRODUCTION: Endobronchial teratomas are extremely rare tumors that develop within the airway of the lung. Patients often present with nonspecific symptoms that depend on the size and anatomic features, making the differential broad and the diagnosis challenging. PRESENTATION OF CASE: A 28-year-old man presented with a 6-month history of a dry cough, vague chest discomfort, and occasional dyspnea. A chest X-ray and CT were performed, revealing a heterogeneous mass involving the mediastinum and the medial aspect of the right lung. Serum tumor markers were normal, and a testicular ultrasound excluded a metastatic germ cell tumor. Definitive treatment required an en bloc resection of the thymus and right upper lobe, with pathologic review showing an endobronchial origin of a mature teratoma. DISCUSSION: This case illustrates the diagnostic challenges of endobronchial teratomas, provides imaging and histologic characteristics of this rare tumor type, and contributes to the number of published cases with favorable outcomes. CONCLUSION: Given the rarity of endobronchial teratomas, a high index of suspicion among pulmonologists, surgeons, and pathologists is necessary to correctly diagnose and treat these patients.