A Fast-growing Benign Metastasizing Leiomyoma Mimicking Malignancy

Area of Science:

• Gynecologic Pathology
• Thoracic Surgery
• Oncology

Background:

• Benign metastasizing leiomyoma is a rare condition where smooth muscle tumors spread to distant sites.
• Fast-growing tumors in the chest can mimic malignancy, necessitating careful diagnosis.

Observation:

• A 52-year-old woman presented with abnormal chest shadows on imaging.
• Chest CT revealed well-circumscribed cystic tumors, raising concern for malignancy due to rapid growth.

Findings:

• Video-assisted thoracic surgery was performed for diagnosis and treatment.
• Pathological examination confirmed benign metastasizing leiomyoma, characterized by cystic changes and smooth muscle cell proliferation.
• Cyst enlargement was identified as a potential driver of the tumor's rapid growth.

Implications:

• Accurate pathological differentiation is essential for distinguishing benign metastasizing leiomyoma from rare cystic malignant diseases.
• This case highlights the importance of comprehensive diagnostic workup for unusual thoracic presentations.