Benign metastasizing leiomyoma of the lung: diagnostic process and treatment based on three case reports and a review of the literature

Abstract

Background: Benign metastasizing leiomyoma (BML) is a rare disorder in women that is most commonly an incidental finding on chest X-rays. Patients share a common history of uterine leiomyoma. The transformed cells metastasize to various locations by an unclear mechanism, especially the lungs (BPML: benign pulmonary metastasizing leiomyoma). The disease takes the form of either, more commonly, multiple nodules or a solitary mass. Despite this pulmonary involvement, patients seldom present with signs of respiratory insufficiency, making diagnosis even more problematic.Case presentations: The three cases described in this paper are not alike. Two patients presented with the more common multiple-nodule variant while the other had a single mass, but all were symptom-free. The first patient was diagnosed with BML at the age of 50, and 12 years prior to the diagnosis, underwent a supracervical hysterectomy. The second patient had a myomectomy at the age of 36, and BML diagnosed 17 years later at the age of 53. The third patient had a hysterectomy with bilateral salpingo-oophorectomy at the age of 46, with lung lesions present before the hysterectomy. All patients underwent a significant number of tests before the decision was made to conduct invasive diagnostic procedures and operate. Immunohistochemical studies of postoperative materials showed positive staining of spindle cells with antibodies against desmin and smooth muscle actin as well as estrogen and progesterone receptors. There were entrapped bronchoalveolar structures stained with the TTF1 antibody. The final histopathological diagnoses were BPML. All patients are stable and symptom-free: two of them at 2 years follow-up and one at 6 months follow-up.Conclusion: A "gold standard" therapy for BML has yet to be established, with authors proposing hormonal manipulation (e.g., anti-estrogen therapy, aromatase inhibitors, gonadotropin-releasing hormone agonists), oophorectomy, and classical resection. This paper adds to the surgical experience in successful BPML management.

Benign metastasizing leiomyoma – a case of benign metastasis

“…Although ulipristal acetate (a selective progesterone receptor modulator) is frequently used as an effective treatment for uterine broids, its effect on BML is uncertain. 6 All patients must be submitted to a long-term follow-up regimen, with imaging reassessment by computed tomography. 3 The authors with this clinical case aim to illustrate an example of a benign histological tumour with a clinical presentation that resembles malignant diseases.…”