A case of primary pleural synovial sarcoma with endobronchial recurrence.

Primary pleural synovial sarcoma (PPSS) is an extremely rare malignancy without a known cause. The diagnosis is made after excluding metastasis from an extra-thoracic sarcoma. We report a case of a 67-year-old gentleman who presented with an incidental finding of a left lung mass on a routine chest X-ray. A computed tomography (CT) of the thorax and whole-body positron emission tomography (PET)-CT was done confirming a left lung mass with no other extra-thoracic involvement. A lobectomy was performed with a diagnostic and therapeutic intent. The histopathological examination and immunohistochemistry study revealed a pleural-based tumour with features suggestive of synovial sarcoma. Subsequently, he underwent post-operative radiotherapy. However, three months later, he developed an endobronchial recurrence, complicated by post-obstructive pneumonia resulting in his demise. This case highlights a rare form of malignancy with a rare site of recurrence.