Abstract
BACKGROUND: Intramuscular hemangioma is an uncommon benign tumor found mainly in the limbs of adolescents and young adults. The local recurrence rate is high, ranging from 30 to 50%, necessitating wide local excision of intercostal intramuscular hemangiomas. However, preoperative diagnosis of intramuscular hemangiomas is challenging. Herein, we report a rare case of an intramuscular hemangioma arising from the chest wall. CASE PRESENTATION: A healthy 29-year-old asymptomatic man was referred to our hospital after an abnormal shadow was observed on his chest radiography. Computed tomography and magnetic resonance imaging revealed a 30-mm-sized mass in the right second intercostal space. Neoplastic lesions, such as schwannomas or solitary fibrous tumors, were included in the preoperative differential diagnosis. Tumor resection was performed using video-assisted thoracoscopic surgery. The tumor, which had a smooth surface covered with parietal pleura, was dissected from the external intercostal muscle and costal bone. Postoperative histopathological examination revealed proliferation of spindle-shaped endothelial cells arranged in a capillary vascular structure accompanied by entrapped smooth muscle fibers, adipose tissue, and muscle vessels. The final diagnosis was an intramuscular hemangioma with negative surgical margins. There was no evidence of recurrence during the 1-year postoperative follow-up period. CONCLUSION: Intramuscular hemangiomas should be considered in the differential diagnosis of chest wall tumors, particularly in young people, owing to their potential for recurrence. Moreover, postoperative follow-up may be necessary for resected intramuscular intercostal hemangiomas.