An Unexpected Diagnosis After a Viral Infection: A Case of a Giant Mediastinal Ganglioneuroma

Ganglioneuromas (GN) are rare, benign tumors that develop from sympathetic ganglia. They usually appear in children and young adults and are mostly found in the posterior mediastinum or retroperitoneum. When they occur in older adults, diagnosis can be complicated due to their slow growth, vague symptoms, and similarities in imaging to other malignant masses in the mediastinum. We describe the case of a 61-year-old woman who had a persistent dry cough, wheezing, and shortness of breath after an influenza infection. Initial medical treatment was ineffective, prompting imaging that showed a heterogeneous mass in the posterior mediastinum with cystic areas and calcifications. A magnetic resonance imaging (MRI) scan revealed a well-defined lesion that was hyperintense on T2 imaging but did not invade nearby structures. Further tests, including bronchoscopy, spectral computed tomography (CT), and endoscopic ultrasound, confirmed a mostly cystic mass that compressed the esophagus but showed no infiltration. A fine-needle aspiration did not provide a diagnosis, so surgical removal was performed. The histopathological examination confirmed it was a GN. This case highlights the diagnostic difficulties of mediastinal GN in older adults, the importance of using multiple imaging methods, and the generally positive outcomes after complete surgical removal.