title: Endobronchial ultrasound-guided fine-needle aspiration cytology of bronchial low-grade mucoepidermoid carcinoma: Rapid on-site evaluation of cytopathologic findings.
abstract: Bronchial mucoepidermoid carcinoma (MEC) is rare, comprising about 0.2% of primary lung tumors. Endobronchial ultrasound (EBUS) guided fine-needle aspiration (FNA) cytology is an integral tool in the diagnosis and staging of malignant lung tumors. Rapid on-site evaluation (ROSE) has been proven useful as a guide for assessing the adequacy and accuracy of the FNA samples. Therefore, comprehensive knowledge of diagnostic cytomorphologic findings of MEC is critical for ROSE. We reported a 46-year-old woman with 6 weeks of cough productive of yellow sputum that did not improve on antibiotics. A chest CT demonstrated a well-circumscribed nodule in the right lower lobe bronchus that extended into the lung parenchyma. EBUS-guided FNA was performed to obtain diagnostic materials. The ROSE of cytology specimen revealed numerous tight clusters of cells with well-defined, but scant cytoplasm. These cells were relatively small and bland with high N/C ratio, resembling benign ductal cells. Neither cilia nor intranuclear inclusions were noted. Focal extracellular metachromatic mucinous materials were also noted. A preliminary diagnosis of "low-grade epithelial neoplasm, favor low grade MEC" was rendered. The definitive diagnosis was confirmed by both cytology and core biopsy. EBUS-guided FNA cytology can be a reliable method for the diagnosis of bronchial low grade MEC. The cyto-morphology of ROSE can indicate the diagnosis of low grade MEC and direct the appropriate follow-up triage of the specimen.
authors.affiliation: Department of Anatomic Pathology, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Kathryn S
authors.initials: KS
authors.lastname: Dyhdalo
authors.forename: Longwen
authors.initials: L
authors.lastname: Chen
mesh_terms: D001980:Bronchi / Q000000981:diagnostic imaging / Q000473:pathology; D001984:Bronchial Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D018277:Carcinoma, Mucoepidermoid / Q000000981:diagnostic imaging* / Q000473:pathology*; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D005260:Female; D006801:Humans; D008875:Middle Aged