AN UNEXPECTED CAUSE OF HEMOPTYSIS: RARE TRACHEAL TUMOR

Abstract

SESSION TITLE: Fellows Lung Cancer Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Leading causes of hemoptysis in the western world are cryptogenic and infectious. We present a case of a young adult with isolated hemoptysis subsequently found to have a rare tracheal tumor. CASE PRESENTATION: A 24 yo male presented to the emergency room with hemoptysis of 3-4 tablespoons of bright red blood. He is a competitive swimmer with past medical history of childhood L5 osteochondroma and no tobacco use history. He had no other symptoms or exercise limitation. Initial chest x-ray and lab work were normal. Chest CT revealed mid-tracheal pedunculated mass obstructing >50% of the tracheal diameter. He was admitted to the hospital where bronchoscopy was performed, revealing a multilobulated and vascular-appearing mass. The patient proceeded to thoracic surgery with trans-cervical resection of the mass on 1 tracheal ring. Pathology revealed carcinoma ex pleomorphic adenoma with negative margins. The malignant component of the tumor was negative for MAML2 rearrangement by fluorescent in situ hybridization and was best characterized as high-grade adenocarcinoma, not otherwise specified. PET-CT and brain MRI were negative for metastatic disease. He received 60 Gy of adjuvant radiation therapy 8 weeks following resection. DISCUSSION: Primary salivary gland-type (P-SGT) tumors arise from the seromucinous submucosal glands of the central airways, and unlike their salivary gland counterparts, tend to be malignant.3 P-SGT of the lung are rare and account for 0.1-0.2% of all lung cancer. Mucoepidermoid carcinoma is the most common, followed by adenoid cystic carcinoma and distantly followed by epithelial-myoepithelial carcinoma. Carcinoma ex pleomorphic adenocarcinoma (Ca ex PA) is exceedingly rare, with 11 cases reported in the literature (4 involving the trachea). This tumor has an abrupt transition from a benign pleomorphic adenoma with bland ductal and myoepithelial components to a high grade malignant carcinoma with marked atypia, necrosis and mitotic activity. This is in contrast to the majority of P-SGT tumors, which are typically low grade and carry an overall prognosis of 56.3% survival at 20 years. Average age of onset for P-SGT tumors is the 5th and 6th decades, including pulmonary Ca ex PA (mean age 54y), which makes this discovery in a young patient highly unexpected. For P-SGT tumors, surgical intervention results in significant improvement in overall survival. The optimal treatment for pulmonary Ca ex PA remains unknown with the majority of reported cases receiving complete resection with varying adjuvant use of radiation and/or chemotherapy. CONCLUSIONS: Ca ex PA of the large airways is extremely rare and, in contrast to the majority of other primary salivary gland-type tumors, is high grade. Optimal treatment strategies remain unknown with resection plus radiation and/or chemotherapy being the most common approach to date. Reference #1: Ittrich H, Bockhorn M, Klose H, Simon M. The Diagnosis and Treatment of Hemoptysis. Dtsch Arztebl Int. 2017;114(21):371-381. Reference #2: Molina JR, Aubry MC, Lewis JE, et al. Primary salivary gland-type lung cancer: spectrum of clinical presentation, histopathologic and prognostic factors. Cancer. 2007;110(10):2253-2259. Reference #3: Falk N, Weissferdt A, Kalhor N, Moran CA. Primary Pulmonary Salivary Gland-type Tumors: A Review and Update. Adv Anat Pathol. 2016;23(1):13-23. DISCLOSURES: No relevant relationships by Mark Allen, source=Web Response No relevant relationships by Jennifer Boland, source=Web Response No relevant relationships by Matthew Cecchini, source=Web Response No relevant relationships by Kimberly Johnson, source=Web Response no disclosure on file for Tobias Peikert