SAT-510 Squamous Cell Carcinoma of the Lung in a Patient Using Inhaled Insulin: A Case Report and Review of Pulmonary Safety Concerns

Abstract Disclosure: A. Aamir: None. M. Khan: None. G. Rodriguez: None. Z. Zavgorodneva: None. G. Bahtiyar: None. Introduction: Lung cancer, including squamous cell carcinoma (SCC), is a leading cause of death. While SCC is linked to smoking and environmental factors, studies suggest Afrezza, an inhaled insulin introduced in 2014, may also pose risks. Case description A 65-year old male with a 24-year history of well-controlled type 1 diabetes mellitus, initially managed with an insulin pump and continuous glucose monitoring (CGM), transitioned to a regimen of Afrezza, long-acting insulin, and CGM in 2021 due to pump functionality issues. The patient has significant secondhand smoke exposure for 35-40 years and smoked cigars for 2-3 years, quitting around 15 years ago. He has also occasionally used marijuana over the past decade. In late 2023, the patient experienced significant, unexplained 15 lbs weight loss in 10 months, attributing it to increased physical activity and stress. Later in March 2024, he presented to the emergency department with chest pain, shortness of breath, and a persistent productive cough. A chest X-ray revealed a mass in the right lung, prompting further investigation. Imaging studies, including PET and CT scans, revealed three masses: a 2.3 cm hypermetabolic lesion in the left kidney, confirmed by biopsy as a clear cell renal cell carcinoma (RCC); a 5 cm mediastinal mass although showing necrotic tissue with no viable cells on biopsy, suggested possible RCC origin; and a 0.3 cm right lower lung nodule, confirmed as a moderately differentiated SCC by biopsy. Afrezza was discontinued following the SCC diagnosis, and the patient has been transitioned to a combination of long and short acting insulins and CGM. Discussion: Inhaled insulin despite benefits in diabetes management, has raised concerns regarding its potential link to lung cancer due to insulin's known carcinogenic properties and localized insulin delivery to the lung. This case report highlights the potential risk of lung cancer associated with Afrezza use. Clinical trials suggest a small association between Afrezza and an increased lung cancer risk, particularly in heavy tobacco users. Given these risks, clinicians should carefully consider alternative treatments for patients with lung disease or cancer risk factors, monitor pulmonary health regularly, and educate patients about potential symptoms. Further research is needed to establish a definitive causal relationship and understand the long-term safety of Afrezza. References: US Prescribing Information – Afrezza. June, 2014. Updated June, 2014. Accessed February, 2020. https://www.accessdata.fda.gov/drugsatfda_docs/label/2014/022472lbl.pdf Presentation: Saturday, July 12, 2025