[Benign metastasizing leiomyoma of the lung--a rare differential diagnosis of pulmonary space-occupying lesions]

Clinical benefit of endocrine therapy for benign metastasizing leiomyoma

Benign metastasizing leiomyoma (BML) is a rare disease that is caused by metastasis of a histologically benign leiomyoma that spreads to distant organs. Metastasis commonly follows surgical treatment of myomectomy or hysterectomy for benign uterine leiomyoma. Since the work of Steiner in 1939, several other studies have been published, but a unified view has not emerged regarding the biological nature, pathogenesis, and prognosis of this disease. In particular, a standard treatment has not been established. Here we report a case of BML of the lung and peritoneum in a premenopausal 45-year-old woman who underwent hysterectomy for uterine leiomyoma 10 years earlier. A computed tomography (CT) scan showed multiple pulmonary nodules (maximum size 48 mm) and a solitary intra-peritoneal nodule. The lung nodules were diagnosed as BML following a CT-guided needle biopsy. Histologically, the biopsied tumor was composed of spindle cells without significant atypia, and mitosis was not observed. Immunohistochemically, the tumor cells were strongly positive for smooth muscle actin, desmin, and estrogen receptor, suggesting a uterine leiomyomatous lineage. The patient was treated with a gonadotropin-releasing hormone agonist for 36 months, during which time the nodules reduced in size slightly. No new lesions appeared, and the tumors were stable at 15 months after the cessation of treatment. In conclusion, endocrine therapy can serve as one of the conservative treatments for premenopausal women with BML, rather than surgery.

Locally relapsed and metastatic uterine leiomyoma: a case report

Introduction

Benign metastasising leiomyoma refers to a type of lesion characterised by leiomyomatous alterations without any indication of malignancy. It presents as either a singular nodule or multiple nodules of proliferating smooth muscle cells and is generally found in the lungs of women who have undergone a hysterectomy. The purpose of this case report is to contribute to the knowledge of this rare disease by presenting evidence and experience of a patient case. In particular, this report seeks to investigate the therapeutic approaches in order to understand whether a standard of care can be prescribed and whether the use of prophylaxis therapy with progesterone as a follow-up to surgery serves as a reasonable treatment in certain cases diagnosed as benign metastasising leiomyoma.

Case presentation

We present the case of a 52-year-old Caucasian woman who developed a pelvic relapse and a pulmonary localisation of benign metastasising leiomyoma following a hysterectomy for myomatous uterus.

Conclusion

Our literature review revealed a single case of the use of chemoprophylaxis as treatment of a benign metastasising leiomyoma. The role of chemoprophylaxis in preventing future recurrences remains unclear. The use of progesterone as an adjuvant therapy for benign metastasising leiomyoma could simply be palliative, with associated psychological benefits, or it could be of therapeutic significance.

Pulmonary benign metastasizing leiomyoma following hysterectomy: a clinicopathologic correlation

Benign metastasizing leiomyoma is a rare condition with fewer than eighty (80) reported cases in the literature. We describe the clinical and pathologic findings in a 49-year-old woman who had undergone hysterectomy 15 years before presentation was referred to evaluate for pulmonary metastases with typical radiologic findings of bilateral multiple pulmonary nodules. Wedge biopsy of the lesion showed characteristic histologic findings of cytologically bland smooth muscle cells with scattered entrapped benign bronchiolar elements. Immunohistochemistry was positive only in smooth muscle cells for desmin, estrogen, and progesterone receptors. The clinical and histologic differential diagnosis and the importance of accurate diagnosis and prognostic significance are emphasized.

Benign metastasizing leiomyoma: clonality, telomere length and clinicopathologic analysis

Benign metastasizing leiomyoma is a rare condition affecting women with a history of uterine leiomyomata and is characterized by multiple histologically benign pulmonary smooth muscle tumors. Speculations on its pathogenesis include a benign uterine leiomyoma colonizing the lung, a metastatic low-grade uterine leiomyosarcoma, and primary pulmonary leiomyomatosis. To elucidate its pathogenesis, we analyzed the clinical, pathological and immunohistochemical features, clonality, and telomere length of multiple lung and uterine tumors in three patients with benign metastasizing leiomyoma. In all cases, pulmonary tumors had benign histology and immunohistochemical profiles (estrogen receptor positive, progesterone receptor positive, and very low proliferative index) identical to uterine leiomyoma. In eight tumors from three patients, clonality was assessed by analyzing the variable length of the polymorphic CAG repeat sequence within the human androgen receptor gene. In the two informative patients pulmonary and uterine tumors showed identical patterns of androgen receptor allelic inactivation, indicating that they were clonal. The telomere length measured by fluorescence in situ hybridization in pulmonary leiomyomas of all three patients were either long or very long and were identical to the uterine counterparts, indicating significant telomere shortening is not a crucial step for developing metastases. Our evidence supports the notion that benign metastasizing leiomyoma is clonally derived from benign-appearing uterine leiomyomas.