Primary pleuropulmonary synovial sarcoma presenting with recurrent spontaneous pneumothorax

Primary pleuropulmonary synovial sarcoma (PPSS) is a rare mesenchymal neoplasm, accounting for less than 0.5% of all primary lung tumours. Presentation is often vague and may include cough, chest pain or dyspnoea. Due to the tumour's rarity, diagnosis can be challenging, and not much is known about the disease process or optimal treatment course. In this case report, we describe an older female patient who underwent blebectomy for recurrent pneumothorax. No masses or suspected lesions were found on CT imaging besides the bleb. The bleb was then found to be PPSS via RT-PCR cytology. This case aims to increase awareness of malignant tumours clinically presenting as recurrent pneumothorax with no discrete lung mass on CT imaging. We also highlight the importance of cytogenetics to confirm the diagnosis of this rare tumour.