SESSION TITLE: Lung Pathology 1 SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Recurrent respiratory papillomatosis (RRP) is a rare disease manifested by the presence of numerous papillomas within the larynx and tracheobronchial tree. Etiologically derived from human papilloma virus (HPV), primarily from serotypes 6 and 11, RRP has a course with a wide spectrum of possibilities including spontaneous regression to malignant transformation. CASE PRESENTATION: A 57-year-old African American male with a 30 pack-year smoking history and medical history of HIV (on ARVs) and tracheobronchial papillomatosis presented as a walk-in to the pulmonary clinic for complaints of hemoptysis, weight loss and fatigue. The physical exam was significant for coarse breath sounds and inspiratory crackles over the right middle and lower lobe. He was not in respiratory distress. He did not have any evidence of oral, sinonasal, laryngeal, anal, or genital papillomatosis. Bronchoscopic tissue sampling 3 months previously confirmed benign papillomatosis. The chest X-ray demonstrated new confluent mass-like consolidation in the right lower lobe and a new medial left lower lobe consolidation. A previous CT of the chest demonstrated collapse of the bilateral lower lobe bronchioles, numerous scattered nodules, and increased consolidative nodularity in the right greater than left lower lobe. He underwent bronchoscopy with biopsy, which demonstrated squamous papilloma with high-grade dysplasia and small cell carcinoma without definite invasion. A PET CT scan demonstrated multiple bilateral nodular densities with intense FDG uptake and no evidence of metastasis. He was referred to oncology and is currently receiving chemotherapy with Carboplatin and Paclitaxel. DISCUSSION: Adult-onset RRP is rare, most commonly occurring in the juvenile age group. Rarer is extension into the lung parenchyma, occurring in less than 1% of patients. Malignant transformation is most rare in this usually benign disease, though active smoking and HIV infection increases the risk of this occurring. In fact, it is known that malignant transformation to squamous cell carcinoma of the anus, also associated with HPV-related papillomatosis, is one of the most frequent non-AIDS defining illnesses in HIV patients. It is thus reasonable to extrapolate from this information that an increased risk for malignant transformation from HPV-related papillomatosis occurs in the lungs as well. To our knowledge, this is the first report of malignant transformation to squamous cell carcinoma of the lung in an HIV-infected individual with adult-onset RRP. CONCLUSIONS: RRP ranges from benign disease to risk for malignant transformation. Behavior modification with smoking cessation and close follow-up are strongly encouraged. Hammoud D, Haddad BE. Squamous cell carcinoma of the lungs arising in recurrent respiratory papillomatosis. Respiratory Medicine CME. 2010;3(4):270-272. https://doi.org/10.1016/j.rmedc.2009.09.021. Reference #1: Xiao Y, Wang J, Han D, Ma L. A Case of the Intrapulmonary Spread of Recurrent Respiratory Papillomatosis With Malignant Transformation. Lopez FA, ed. The American Journal of the Medical Sciences. 2015;350(1):55-57. https://doi.org/10.1097/MAJ.0000000000000370. Reference #2: Moanna A, Flenaugh EL, Lennox JL, Moss M, Vuchetich A. Severe Recurrent Respiratory Papillomatosis in an HIV-infected Adult on Highly Active Antiretroviral Therapy. Journal of Bronchology. 2005;12(4):210-213. https://doi.org/10.1097/01.lab.0000174647.08643.cc.Hidalgo-Tenorio Reference #3: C, Gil-Anguita C, Ramírez-Taboada J, et al. Risk factors for infection by oncogenic human papillomaviruses in HIV-positive MSM patients in the ART era (2010–2016). Maatouk. I, ed. Medicine. 2017;96(39):e8109. https://doi.org/10.1097/MD.0000000000008109. DISCLOSURES: No relevant relationships by Aarti Duggal, source=Web Response No relevant relationships by Eric Flenaugh, source=Web Response No relevant relationships by Marilyn Foreman, source=Web Response No relevant relationships by Marina Mosunjac, source=Web Response No relevant relationships by Snigdha Nutalapati, source=Web Response No relevant relationships by Dana Thomas, source=Web Response