Abstract
RATIONALE: Primary pulmonary alveolar soft part sarcoma (ASPS) is an extremely rare disease characterized by a specific genetic abnormality - the ASPSCR1-TFE3 gene fusion. PATIENT CONCERNS: This study presented a 27-year-old male patient who experienced persistent chest tightness for over 6 months. DIAGNOSES: The computed tomography (CT) scan and enhanced CT scan revealed a mass in the medial segment of the right middle lobe of his lung. The patients then underwent further diagnosis. Pathological examination showed the tumor to be consisting of polygonal cells with abundant eosinophilic or transparent cytoplasm arranged in nests. Next-generation sequencing reported ASPSCR1-TFE3 gene fusion, confirming the final diagnosis of primary pulmonary ASPS. Regular follow-ups of 12 months showed no signs of tumor recurrence. INTERVENTIONS: The patients underwent the medial segment resection of the right middle lobe for treatment. OUTCOMES: A CT examination 3 months after the operation showed that the patient had improved. The last review showed no recurrence or metastasis. LESSONS: This case report highlights the importance of detailed diagnosis, prompt treatment, and close monitoring of patients with ASPS.