Thoracic follicular dendritic cell sarcoma - an outlandish presentation of a rare tumour with review of literature.

Follicular dendritic cell sarcoma is a rare low grade malignant neoplasm that arises from follicular dendritic cells in lymphoid tissue germinal centres and accounts for 0.4% of all soft tissue sarcomas. It is extremely rare to have pulmonary follicular dendritic cell sarcoma with endobronchial extension and as an anterior mediastinal mass with mediastinal lymph node involvement. We present the case of a 34-year-old male non-smoker who had been experiencing chest pain for three months. A lobulated left peri-hilar mass with endobronchial spread into the left main bronchus and mediastinal lymphadenopathy was identified on a chest CT. The bronchoscope-guided cryobiopsy of the endobronchial mass was inconclusive. After a thorough multidisciplinary discussion, the patient underwent left sided pneumonectomy, mediastinal mass resection, and systematic lymph node dissection. Histologic examination using immunohistochemistry revealed follicular dendritic cell sarcoma.