Primary Pulmonary Synovial Sarcoma: An Exceedingly Rare Pulmonary Malignancy Presenting as an Obstructing Endobronchial Mass

Abstract

SESSION TITLE: Lung Cancer Case Report Posters II SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 27, 2015 at 01:30 PM - 02:30 PM INTRODUCTION: Primary pulmonary synovial sarcomas (PPSS) are exceedingly rare tumors. We report a case of PPSS presenting as an obstructing endobronchial lesion. This case highlights the importance of appropriate cytogenetic testing in the diagnosis of this rare tumor. CASE PRESENTATION: An 83-year-old Caucasian female presented to her primary care physician with a 3-week history of progressive dyspnea and hemoptysis. Medical history was significant for a prior stable pulmonary nodule and previous pontine stroke. Vital signs were notable for a respiratory rate of 26 and oxygen saturations of 82% on room air. Physical examination revealed reduced air entry on the right, with occasional wheezing. Cardiac and abdominal examination was unremarkable. She underwent chest radiography that showed right lower lobe collapse. She then proceeded to a computed tomography (CT) scan of the chest that showed a right hilar mass causing right mainstem obstruction, right lower lobe atelectasis and a presumed post-obstructive pneumonia (Figure 1). She proceeded to bronchoscopy where a large endobronchial mass was noted near the take off of the superior segment of the right lower lobe (Figure 2). Biopsies showed sarcoma cells. Fluorescent in-situ hybridization (FISH) testing showed rearrangement of the gene SS-18 at 18q11.2, indicating a primary pulmonary synovial sarcoma. Thorough focused physical examination and full body CT/PET demonstrated no other lesions. She underwent radiation therapy with 6600 cGys in 33 fractions with curative intent. At 1-year follow-up she is in complete remission. DISCUSSION: Synovial sarcomas (SS) are uncommon, accounting for 10% of all sarcomas. Synovial sarcomas typically occur in soft tissues and extremities. Definitive diagnosis of SS requires cytogenetic demonstration of SS-18 genetic rearrangement at 18q11.2 by FISH, present in 90% of synovial sarcomas. PPSS is rare, but is increasingly recognized with improvements and wider availability of cytogenetic testing. PPSS presenting as an obstructing endobronchial tumor has only been reported on few occasions previously. CONCLUSIONS: Primary pulmonary synovial sarcomas are rare malignancies that may present as obstructing endobronchial lesions. Wider availability of cytogenetic testing may lead to an increased recognition of this entity. Radiation therapy with curative intent is a viable treatment option. Reference #1: Primary pulmonary synovial sarcoma: a rare primary pulmonary tumor. Falkenstern-Ge RF et al. Lung. 2014 Feb;192(1):211-4. DISCLOSURE: The following authors have nothing to disclose: Hemang Yadav, Rodrigo Cartin-Ceba No Product/Research Disclosure Information