BACKGROUND: Lung mucoepidermoid carcinoma is a form of non-small cell lung carcinoma that originates from the submucosal glands of the tracheobronchial tree; it is rare and causes 0.1% to 0.2% of lung malignancies. In this article, we report on an occurrence of this condition in an 81-year-old male, which is rare occurrence in this age group. In this case, we found a history of smoking and asbestos exposure which might suggest that exposure to both of these factors can possibly increase the risk for this malignancy.

CASE REPORT: An 81-year-old male presented with chronic cough and yellow sputum, associated with right upper back pain. The patient was a smoker of 30 packs per year and reported a history of asbestos exposure. He had past medical history of rectal cancer, but no previous history of salivary glands tumors. Physical examination was normal, laboratory investigations were unremarkable. Computed tomography chest showed endobronchial mass with post-obstructive atelectasis. Bronchoscopic evaluation revealed a whitish, endobronchial mass occluding the posterior segment of the right lower lobe. Biopsy showed benign squamous papilloma and malignancy was not excluded as only superficial parts of the mass were obtained. The decision was made to remove the lesion. A right lower lobectomy was done, and histopathology revealed a low grade mucoepidermoid carcinoma; immunohistochemical staining showed tumor cells positive for p40 and p63 supporting the diagnosis. No further adjuvant treatment was recommended, and follow-up imaging was planned for surveillance.

CONCLUSIONS: Mucoepidermoid carcinoma of the lung is a rare form of non-small cell lung carcinoma. Appropriate diagnosis requires correctly interpreted biopsy results along with immunohistochemical staining results.

Keywords: Carcinoma, Mucoepidermoid