Benign metastasizing leiomyoma is exceedingly rare. Pulmonary benign metastasizing leiomyoma is defined as the metastasis of leiomyoma to the lung tissue. It has a benign histological character, but the presence of metastasis is contradictory. First reported in 1937, it is generally seen among women of young reproductive age and premenopausal women who have undergone uterine leiomyoma or hysterectomy, and the most common site of metastasis is the lung. The prognosis is generally very favorable, and it rarely undergoes a malignant transformation. However, various studies suggest that pulmonary and pleural leiomyoma may cause acute respiratory failure. Radiological findings have a wide spectrum ranging from primary malignant neoplasms to metastatic diseases. Benign metastasizing leiomyoma is usually incidentally found on chest x-rays, and it appears as nodules arising from the benign proliferation of smooth muscles. Here, we present a 46-year-old patient who had a hysterectomy 15 years ago due to uterine leiomyoma and was recently diagnosed with benign leiomyoma which metastasized to the lung. It should be kept in mind that benign leiomyomas with pulmonary metastasis may rarely undergo malignant transformation. '+st+' Kayser K, Zink S, Schneider T, Dienemann H, André S, Kaltner H, et. al. Benign metastasizing leiomyoma of the uterus: Documentation of clinical, immunohistochemical and lectin-histochemical data of ten cases. Virchows Arch. 2000;37:284-92. Chen S, Liu R-M, and Li T. Pulmonary benign metastasizing leiomyoma: a case report and literature review. J Thorac Dis. 2014;6(6):E92–E98. Kang MW, Kang SK, Yu JH, Lim SP, Suh KS, Ahn JS, et al. Benign metastasizing leiomyoma: metastasis to rib and vertebra. Ann. Thorac Surg. 2011;91(3):924–926. Parenti DJ, Morley TF, Giudice JC. Benign metastasizing leiomyoma: a case report and review of literature. Respiration. 1992;56:347350. Takemura G, Takatsu Y, Kaitani K, Ono M, Ando F, Tanada S, et al. Metastasizing uterine leiomyoma: a case with cardiac and pulmonary metastasis. Pathol Res Pract. 1996;192:622-629. Uyama T, Monden Y, Harada K, Sumitomo M, Kimura S. Pulmonary leiomyomatosis showing endobronchiab extension and giant cyst formation. Chest. 1988;94:644-646. Cramer SF, Patel A. The frequency of uterine leiomyomas. Am J Clin Pathol. 1990;94:435-8. Chen S, Liu RM, Li T. Pulmonary benign metastasizing leiomyoma: a case report and literature review. J Thorac Dis. 2014;6:E92-8. Bharambe BM, Deshpande KA, Surase SG, Ajmera AP. Malignant transformation of leiomyoma of uterus to leiomyosarcoma with metastasis to ovary. J Obstet Gynaecol India. 2014;64:68-9. Arnold LM, Burman SD, O-Yurvati AH. Diagnosis and management of primary pulmonary leiomyosarcoma. J Am Osteopath Assoc. 2010;110:244-6. Pastré J, Juvin K, Grand B, Gibault L, Valcke J, Israël-Biet D. Pulmonary benign metastasizing leiomyoma presented as acute respiratory distress. Respirology. 2017;5(2):00216. doi: 10.1002/rcr2.216. Egberts JH, Schafmayer C, Bauerschlag DO, Jänig U, Tepel J. Benign abdominal and pulmonary metastasizing leiomyoma of the uterus. Arch Gynecol Obstet. 2006;274:319-22. Esteban JM, Allen WM, Schaerf RH. Benign metastasizing leiomyoma of the uterus: histologic and immunohistochemical characterization of primary and metastatic lesions. Arch Pathol Lab Med. 1999;123:960-2. Ogawa M, Hara M, Ozawa Y, Moriyama S, Yano M, Schimizu S, et al. Benign metastasizing leiomyoma of the lung with malignant transformation mimicking mediastinal tumor. Clin Imaging. 2011;35:401-4. Mahadevia PS, Tanaka K, Fineberg S. Rosai and Ackerman's surgical pathology, 9th edition author: Juan Rosai Mosby, Edinburgh, 2004. Diagn Cytopathol. 2006;34:382-3. Copyright (c) 2021 Suphi Aydın, Gürhan Öz, Ahmet Dumanlı, Adem Gencer, Aydın Balcı, Funda Demirağ This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.