Pulmonary Benign Metastasizing Leiomyoma: An Extremely Rare Case

Abstract

Benign metastasizing leiomyoma is typically seen in young premenopausal women after a mean period of 15 years following uterine leiomyoma or hysterectomy surgery. They are usually incidentally seen on chest x-rays and are nodular lesions that appear as bilateral nodules with a benign appearance and consist of smooth muscle proliferation. A 44-year-old female presented at her healthcare institution for backache for the last 9 months. Multiple nodules (largest 15 mm) scattered in both lungs and consistent with metastases were detected on computed tomography. The PET-CT results revealed multiple nodular densities with increased metabolic activity (SUVmax: 1.92) in both lungs, with the largest one measuring approximately 15 mm and located in the lower lobe superior segment of the right lung. A benign metastasizing leiomyoma was diagnosed with open wedge biopsy of the lung. We present this case due to its interesting clinical presentation and rarity and emphasize the pathogenesis.