Primary endobronchial epithelial-myoepithelial carcinoma: A case report and literature review

Pulmonary epithelial-myoepithelial carcinoma (P-EMC) is a rare type of salivary gland tumour of the lung. Due to its rarity and lack of long-term follow-up data, there is no established standard for optimal treatment or duration of follow-up. The present study reports the case of a 58-year-old female patient with P-EMC originating from the middle part of the bronchus and presenting as an endobronchial mass in the left superior lobe. Transbronchial forceps biopsy was performed on the visible neoplasm in the left superior lobe, which revealed atypical epithelial cells with a possible diagnosis of mucoepidermoid carcinoma. The patient subsequently underwent left upper lobectomy with mediastinal lymph node dissection. The decision for resection was made based on the absence of abnormalities in the patient's head and neck MRI scan, bone scintigraphy and contrast-enhanced whole-body CT scan, along with the consensus reached by the multidisciplinary treatment team. Final histopathology of the resected specimen confirmed P-EMC. The patient remained free of recurrence and metastasis 5 years post-surgery. Diagnosis of P-EMC from transbronchial forceps biopsy samples is difficult due to its rarity, insufficient sampling and dual histological phenotype. The current study reported a rare case of primary P-EMC initially suspected to be mucoepidermoid carcinoma based on biopsy. Postoperative pathology confirmed the diagnosis of P-EMC. Based on this case and a literature review, for endobronchial EMC lesions confined to the bronchus measuring <2 cm without metastasis, bronchoscopic intervention or video-assisted thoracoscopic segmentectomy may be viable therapeutic alternatives. For nonmetastatic central lesions >2 cm, lobectomy or wedge resection should be considered to avoid the more traumatic pneumonectomy whenever possible.