SESSION TITLE: Lung Cancer Case Report Posters 2SESSION TYPE: Case Report PostersPRESENTED ON: 10/17/2022 12:15 pm - 01:15 pmINTRODUCTION: We present a case of previously unreported primary human papillomavirus (HPV) associated tracheal small cell carcinoma.CASE PRESENTATION: A 66-year-old male with a history of chronic obstructive pulmonary disease and cirrhosis was referred to Interventional Pulmonary Clinic for evaluation of a tracheal lesion. 18 months prior to referral he presented with a painful right neck mass and was diagnosed with stage III (cT4N1M0) HPV-mediated oropharyngeal squamous cell carcinoma with tracheal involvement, which was believed to be a separate focus of tracheal involvement. PET-CT revealed a 4.7cm hypermetabolic parapharyngeal mass, hypermetabolic paratracheal lymph nodes, and a 1.7cm hypermetabolic soft tissue irregularity along the right upper tracheal wall. The patient completed concurrent chemoradiation with cisplatin. Post-treatment imaging showed no evidence of disease, however surveillance CT chest obtained one year later demonstrated an increase of the ill-defined soft tissue infiltration and nodularity of the anterior trachea extending from the thoracic inlet to the proximal mainstem bronchi, with concern for local invasion. The patient underwent rigid bronchoscopy which revealed a tracheal mass resulting in 20% obstruction of the affected airway. Endobronchial biopsy was performed. The endobronchial obstruction was treated with cryoprobe ablation and rigid coring, with reduction in airway obstruction to 10%. Histopathology showed high-grade neoplastic cells with scant cytoplasm, in a background of necrosis, crush artifact, and numerous apoptotic bodies. Tumor cells were positive for pancytokeratin, thyroid transcription factor 1, synaptophysin, and p16 and negative for p40 and leukocyte common antigen. In situ hybridization for HR-HPV was positive and the patient was diagnosed with tracheal HPV-associated small cell carcinoma.DISCUSSION: The most common histologic subtypes of tracheal neoplasms are squamous cell carcinoma (50%) and adenoid cystic carcinoma (10-15%). Tracheal small cell carcinoma is very rare and is considered a neuroendocrine tumor, similar to small cell lung cancer [1]. Human papillomavirus (HPV) has an established pathogenic role in the development of both oropharyngeal squamous cell carcinoma [2] and has been associated with pulmonary squamous cell carcinoma. There are occasional case reports of HPV-associated oropharyngeal small cell carcinoma [3], however a case of HPV-associated tracheal small carcinoma has never been described. In this case the patient had previous biopsy-proven tracheal squamous cell carcinoma, so it is possible that this represents evolution of the patient's squamous cell carcinoma to small cell carcinoma versus a tracheal primary.CONCLUSIONS: We report a case of HPV-related tracheal carcinoma consistent with small cell carcinoma. Given this is a novel disease entity, the optimal treatment regimen and natural history are unknown.Reference #1: Wu CC, Shepard JA. Tracheal and airway neoplasms. Semin Roentgenol. 2013;48(4):354-364. doi:10.1053/j.ro.2013.03.018Reference #2: Elrefaey S, Massaro MA, Chiocca S, Chiesa F, Ansarin M. HPV in oropharyngeal cancer: the basics to know in clinical practice. Acta Otorhinolaryngol Ital. 2014;34(5):299-309.Reference #3: Bishop JA, Westra WH. Human papillomavirus-related small cell carcinoma of the oropharynx. Am J Surg Pathol. 2011;35(11):1679-1684. doi:10.1097/PAS.0b013e3182299cdeDISCLOSURES: Consultant relationship with medtronic Please note: 2019-2021 by George Cheng, value=Consulting feeConsultant relationship with boston scientific Please note: 2019-2021 by George Cheng, value=Consulting feeConsultantOwner/Founder relationship with restor3D Please note: 2016-present by George Cheng, value=Ownership interestConsultant relationship with Intuitive Surgical Please note: 2019-2021 by George Cheng, value=Consulting feeNo relevant relationships by Grace LinNo relevant relationships by Russell MillerNo relevant relationships by William MitchellResearch Funds relationship with Body Vision Please note: 2021-2022 Added 04/04/2022 by Matthew Nobari, value=Grant/Research SupportConsultant relationship with Intuitive Surgical Please note: 2022 Added 04/04/2022 by Matthew Nobari, value=Consulting feeAdvisory Committee Member relationship with Noah Medical Please note: 2022 Added 04/04/2022 by Matthew Nobari, value=HonorariaNo relevant relationships by Angel Rolando PeraltaNo relevant relationships by Alyssa SelfNo relevant relationships by Vera Vavinskaya SESSION TITLE: Lung Cancer Case Report Posters 2 SESSION TYPE: Case Report Posters PRESENTED ON: 10/17/2022 12:15 pm - 01:15 pm INTRODUCTION: We present a case of previously unreported primary human papillomavirus (HPV) associated tracheal small cell carcinoma. CASE PRESENTATION: A 66-year-old male with a history of chronic obstructive pulmonary disease and cirrhosis was referred to Interventional Pulmonary Clinic for evaluation of a tracheal lesion. 18 months prior to referral he presented with a painful right neck mass and was diagnosed with stage III (cT4N1M0) HPV-mediated oropharyngeal squamous cell carcinoma with tracheal involvement, which was believed to be a separate focus of tracheal involvement. PET-CT revealed a 4.7cm hypermetabolic parapharyngeal mass, hypermetabolic paratracheal lymph nodes, and a 1.7cm hypermetabolic soft tissue irregularity along the right upper tracheal wall. The patient completed concurrent chemoradiation with cisplatin. Post-treatment imaging showed no evidence of disease, however surveillance CT chest obtained one year later demonstrated an increase of the ill-defined soft tissue infiltration and nodularity of the anterior trachea extending from the thoracic inlet to the proximal mainstem bronchi, with concern for local invasion. The patient underwent rigid bronchoscopy which revealed a tracheal mass resulting in 20% obstruction of the affected airway. Endobronchial biopsy was performed. The endobronchial obstruction was treated with cryoprobe ablation and rigid coring, with reduction in airway obstruction to 10%. Histopathology showed high-grade neoplastic cells with scant cytoplasm, in a background of necrosis, crush artifact, and numerous apoptotic bodies. Tumor cells were positive for pancytokeratin, thyroid transcription factor 1, synaptophysin, and p16 and negative for p40 and leukocyte common antigen. In situ hybridization for HR-HPV was positive and the patient was diagnosed with tracheal HPV-associated small cell carcinoma. DISCUSSION: The most common histologic subtypes of tracheal neoplasms are squamous cell carcinoma (50%) and adenoid cystic carcinoma (10-15%). Tracheal small cell carcinoma is very rare and is considered a neuroendocrine tumor, similar to small cell lung cancer [1]. Human papillomavirus (HPV) has an established pathogenic role in the development of both oropharyngeal squamous cell carcinoma [2] and has been associated with pulmonary squamous cell carcinoma. There are occasional case reports of HPV-associated oropharyngeal small cell carcinoma [3], however a case of HPV-associated tracheal small carcinoma has never been described. In this case the patient had previous biopsy-proven tracheal squamous cell carcinoma, so it is possible that this represents evolution of the patient's squamous cell carcinoma to small cell carcinoma versus a tracheal primary. CONCLUSIONS: We report a case of HPV-related tracheal carcinoma consistent with small cell carcinoma. Given this is a novel disease entity, the optimal treatment regimen and natural history are unknown. Reference #1: Wu CC, Shepard JA. Tracheal and airway neoplasms. Semin Roentgenol. 2013;48(4):354-364. doi:10.1053/j.ro.2013.03.018 Reference #2: Elrefaey S, Massaro MA, Chiocca S, Chiesa F, Ansarin M. HPV in oropharyngeal cancer: the basics to know in clinical practice. Acta Otorhinolaryngol Ital. 2014;34(5):299-309. Reference #3: Bishop JA, Westra WH. Human papillomavirus-related small cell carcinoma of the oropharynx. Am J Surg Pathol. 2011;35(11):1679-1684. doi:10.1097/PAS.0b013e3182299cde DISCLOSURES: Consultant relationship with medtronic Please note: 2019-2021 by George Cheng, value=Consulting fee Consultant relationship with boston scientific Please note: 2019-2021 by George Cheng, value=Consulting fee Consultant Owner/Founder relationship with restor3D Please note: 2016-present by George Cheng, value=Ownership interest Consultant relationship with Intuitive Surgical Please note: 2019-2021 by George Cheng, value=Consulting fee No relevant relationships by Grace Lin No relevant relationships by Russell Miller No relevant relationships by William Mitchell Research Funds relationship with Body Vision Please note: 2021-2022 Added 04/04/2022 by Matthew Nobari, value=Grant/Research Support Consultant relationship with Intuitive Surgical Please note: 2022 Added 04/04/2022 by Matthew Nobari, value=Consulting fee Advisory Committee Member relationship with Noah Medical Please note: 2022 Added 04/04/2022 by Matthew Nobari, value=Honoraria No relevant relationships by Angel Rolando Peralta No relevant relationships by Alyssa Self No relevant relationships by Vera Vavinskaya