EP1.09-11 Lipoid Pneumonia Resembling Bilateral Lung Cancer: Be Aware of Nasal Decongestants!

Abstract

To describe a case of bilateral exogenous lipoid pneumonia mimicking lung cancer in a patient affected by obstructive sleep apnea syndrome treated with decongestants mineral oils. A 57 year-old male patient was referred to our surgical department for an incidental finding of a bilateral pulmonary mass during a chest X-ray made for chronic coughing. His past medical history was unremarkable; he was an everyday smoker with a 80pack/years and he was affected by obstructive sleep apnea syndrome. A chest CT and CT/PET scans was subsequently done and revealed the presence of a both pulmonary consolidations of the lower lobes bilaterally with increase in uptake of FDG (Fig. 1A-B): mediastinal lymph node was normal, no other lesions was found. Morphology of the lesions was strongly suspect for non small cells lung cancer, so the patient underwent a CT-guided lung biopsy. A percutaneous CT-guided lung biopsy was done in the right lower lobe. The histological examination was consistent with pulmonary adenocarcinoma with signet-ring cell features (Fig.1C): therefore, the patient was addressed to conventional chemotherapy. At that point, a multidisciplinary discussion was done: a careful revision of the chest CT-scan was carried out and focal areas of fat attenuation within the lung consolidations were observed. According to that finding, a diagnosis of lipoid pneumonia was hypothesized. A more careful questioning about patient’s medical history revealed the use of daily nasal decongestants during the last 4 years due to chronic rhinitis secondary to OSAS: the drug was composed of mineral oils. A further blind revision of the histological tissue samples was requested and confirmed the diagnosis of exogenous lipoid pneumonia. The patient was invited to discontinue the nasal oil decongestant. No other pharmacological treatment was started. Six months later, a chest CT-scan was performed but no significant changing of the pulmonary consolidations were observed (Fig. 1D). Currently, the patient is well and a reduction of chronic coughing was reported. Exogenous lipoid pneumonia is a rare condition that might be misdiagnosed with lung cancer; for this reason it should be considered in the differential diagnosis of pulmonary consolidations, especially when occurring bilaterally. A precise medical history could be resolutive.