MIXED GERM CELL TUMOR PRESENTING AS LARGE MEDIASTINAL MASS

Abstract

SESSION TITLE: Fellows Disorders of the Mediastinum Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Extragonadal Germ cell tumors involving the mediastinum are rare and accounts for 3-4% of all germ cell tumors1.Literature review showed only small number of case reports about mixed germ cell tumors involving mediastinum or lungs. We present a rare case of young female presented with very large mediastinal mass. CASE PRESENTATION: 27-year-old female with no significant past medical history presented to the emergency room for the complaint of left-sided chest. She states she has been having intermittent chest pain for the last 2 months with pain radiates to left upper back, describes pain as sharp and stabbing in nature, gets worse with breathing movement and progressively getting worse. She also had night sweats and productive cough but denied any fevers, chills, weight loss, hemoptysis. Patient is never smoker and denied any second hand smoke exposure. Blood work-up was unremarkable, EKG showed sinus tachycardia. Chest x-ray showed left hemithorax opacification concerning for mass, she had CT chest done which showed massive left hilar mass. Patient underwent CT-guided biopsy which showed possible teratoma versus pulmonary hamartoma. Cardiothoracic surgery was consulted and patient underwent left thoracotomy with excision of left-sided intrathoracic mass. Pathology results consistent with mixed germ cell tumor comprised of teratoma with yolk sac tumor. Patient did well after surgery and discharged home with oncology follow-up. DISCUSSION: The differential diagnosis of mediastinal tumors is challenging and includes thymomas, esophageal/thyroid cancers, lymphomas, bronchogenic cysts and extra gonadal germ cell tumors. Germ cell tumors include Teratoma (mature and immature), Yolk sac tumor, Seminoma, Choriocarcinoma, Embryonal carcinoma and Mixed germ cell tumors. Germ cell tumors account for 20% of mediastinal tumors with teratoma and seminomas being most common cause. Because of multiple components of tumor, sampling of mediastinal germ cell tumors can be misleading. In one case report the germ cell tumor was misdiagnosed as hemangioma and in other case report, biopsy led to life threatening bleeding resulting in death of patient. Presenting symptoms include chest pains, shortness of breath, hemoptysis, and trichoptysis (expectoration of hair).Treatment options include complete surgical resection and chemotherapy. Complete resection is important as survival rate is low for patients with residual tumors. Mixed germ cell tumors with malignant components are more aggressive with survival rate less than 2 years. CONCLUSIONS: Extra gonadal Germ cell tumor involving mediastinum are rare, physicians need to be aware of difficulties and complications associated with diagnosis. Germ cell tumors should be considered in differential diagnosis of mediastinal mass especially in young patients. Reference #1: Moreira AL, Ströbel P, Chan JKC et al. Germ cell tumours of the mediastinum. Seminoma. In: WHO Classification of Tumours of Lung, Pleura, Thymus and Heart, 4th edn. IARC, Lyon 2015; 244–8. Reference #2: Sakane T, Okuda K, Murase T, Watanabe T, Oda R, Tatematsu T, Yokota K, Haneda H, Inagaki H, Nakanishi R. Mixed-type primary germ cell tumor of the mediastinum in a young adult male with a sudden life threatening condition: A case report. Thorac Cancer. 2020 Jan;11(1):166-169. doi: 10.1111/1759-7714.13231. Epub 2019 Nov 6.PMID: 31693305 DISCLOSURES: No relevant relationships by Imran Amer, source=Web Response No relevant relationships by Adnan Khan, source=Web Response No relevant relationships by Sana Khan, source=Web Response No relevant relationships by Thomas Maloney, source=Web Response No relevant relationships by Moeez Qureshi, source=Web Response