Giant primary low-grade fibromyxoid sarcoma arising from the left pulmonary parenchyma: A case report and literature review.

Background: Low-grade fibromyxoid sarcoma is a rare painless neoplasm that primarily grows in young adults' proximal extremities and trunks. The lungs are infrequent sites for this type of sarcoma.

Case Presentation: We reported a 26-year-old female that presented with a chief complaint of chest pain from a few months ago to Kasra hospital, Tehran, Iran, in August 2021. Chest computed tomography (CT) showed a hypodense mass with a well-defined margin measuring 9.3 cm in the left upper lobe and multiple hypodense lesions with a lobulated appearance with a total diameter of 15.5 × 13.5 cm in the left lower lobe of the lung.

Conclusion: This is the largest case of primary pulmonary low-grade fibromyxoid sarcoma (30 × 28 × 7 cm), which seemed unresectable at first evaluation. Due to the extent of the tumor, left pneumonectomy was performed, leading to attenuation of symptoms and no recurrence at a six-month follow-up.