Giant posterior mediastinal schwannoma with ancient features

Schwannomas are the most common posterior mediastinal neurogenic tumors. They typically grow insidiously and are often incidentally found in older adults on imaging performed for other reasons. The size of these lesions is usually less than 10 cm and they are often asymptomatic. However, here we describe the case of a young adult with a symptomatic 11×13 cm posterior mediastinal schwannoma with focal ancient features. Briefly, a 23-year-old non-smoking female with a past medical history of scoliosis presented to her primary care provider with complaints of 2 years of intermittent cough and vague chest heaviness that was worse when lying on her right side. She denied any shortness of breath, difficulty breathing, or chest pain. A chest-X-ray showed a large apical mass in the right hemithorax and computed tomography (CT) imaging revealed a large posterior apical mass with midline shift of the upper mediastinal contents and resultant tracheal narrowing. She underwent additional imaging and then a right thoracotomy with excision of an 11×13 cm apical mass. Pathology revealed a schwannoma with focal ancient features and expression of S100. Her post-operative course was relatively unremarkable, except that she did develop contralateral compensatory flushing and hyperhidrosis with exercise. This is indicative of division of the ipsilateral sympathetic chain during excision. Given the size of the mass and pathologic findings she had a repeat CT scan 6 and 24 months post-operatively to demonstrate absence of recurrence.