Primary bronchial leiomyosarcoma: a diagnostic challenge.

Background: Pulmonary bronchial leiomyosarcoma is an extremely rare malignant tumour of the lung originating from the mesenchymal tissue. The retroperitoneal region is the most common site of leiomyosarcoma. It exhibits a high degree of malignancy and a poor prognosis, thereby highlighting the significance of early diagnosis of this disease.

Case demonstration: A 61-year-old male with a smoking history of 40 + years was admitted to the hospital due to cough, expectoration, and shortness of breath that extended for half a year, which aggravated for two months and was succeeded by intermittent bloody sputum for one month. Chest computed tomography (CT) revealed a mass in the upper lobe of the right lung, which was identified as a malignant tumour lesion involving the upper thoracic oesophagus. The boundaries of the mass with the trachea, brachiocephalic artery, and right brachiocephalic vein were unclear. Brush liquid-based cytology of the right middle lobe bronchus was performed, followed by histopathological biopsy. The pathological diagnosis was leiomyosarcoma in the middle lobe of the right lung. After the diagnosis, he underwent chemotherapy in another hospital, and the case was followed up for six months, during which no recurrence was noted.

Conclusions: Pulmonary and bronchial leiomyosarcomas often occur in young males with rapid progression and poor prognosis, but metastasis is rare. Surgical resection is the first-line treatment. We report a case of pulmonary bronchial leiomyosarcoma. The cytological, histological, immunohistochemical, and differential diagnoses were analysed to improve the understanding of the disease. Presently, there exist some challenges in diagnosing and treating pulmonary bronchial leiomyosarcoma. Early detection and treatment are important to improve prognosis.