Benign metastasizing leiomyoma – a case of benign metastasis

Leiomyomas are benign tumours of smooth muscle cells that most often affect the female genital tract, but their metastasis to extra-uterine locations represent rare, yet misunderstood phenomena. The authors present a clinical case of a 42-year-old woman, who underwent a hysterectomy 15 years ago due to myomas, admitted with multiple pulmonary nodules and abdominal mass, diagnosed by imaging tests, in the context of haemoptysis. The anatomopathological exams of the pulmonary and abdominal lesions were compatible with the diagnosis of benign metastatic leiomyoma. Benign metastatic leiomyoma is a rare condition that particularly affects women of childbearing age, with a history of hysterectomy for uterine fibroids. Hence, this entity must be considered in the differential diagnosis of women with pulmonary nodules of uncertain aetiology.

Benign Metastasizing Leiomyoma in the Lung Presenting in a Phyllodes-Like Pattern Mimicking a Biphasic Tumor: A Case Report

Primary biphasic tumors of the lung are rare. Lung lesions with a biphasic pattern are far more commonly primary or metastatic soft tissue tumors with entrapped native respiratory epithelium, giving the false impression of a biphasic tumor. We report a case of bilateral benign metastasizing leiomyomas in a 69-year-old female where the tumor cells diffusely entrapped native respiratory glands in a phyllodes-like pattern. The radiographic characteristics and histologic appearance were not immediately diagnostic and covered a wide differential. Reaching the final diagnosis required the use of immunohistochemical studies as well as correlation with the patient's history and radiographic findings. To the best of our knowledge, this is the first report of pulmonary benign metastasizing leiomyoma presenting in a phyllodes-like pattern. This case illustrates the importance of considering entrapment of native lung epithelium in the differential diagnosis of biphasic-appearing lung tumors.

[18F]-FDG PET/CT of the Pulmonary Benign Metastasizing Leiomyoma in a Breast Cancer Patient: A Case Report

18F-fluorodeoxyglucose ([18F]-FDG) positron emission tomography/computed tomography (PET/CT) is a useful functional image technique to evaluate the disease extent in many cancers, as well as differentiate benign disease from malignant metastasis. We report the case of a 49-year-old woman with breast cancer and suspected lung metastasis by conventional images. After FDG-PET/CT demonstrating faint, or even no FDG uptake in bilateral pulmonary nodules, accompanied with obvious uterine fibroids, benign metastasizing leiomyoma (BML) of the lung was included in a differential diagnosis and finally confirmed by surgical pathology. FDG PET/CT showed its value in the diagnosis of BML in the breast cancer patient who was misleading as lung metastasis during outpatient follow-up.

Benign Metastasizing Leiomyoma of the Uterus with Pulmonary and Bone Metastases

Benign metastasizing leiomyoma (BML) is a rare spindle cell neoplasm seen in middle-aged women who have a history of leiomyoma of the uterus. The most common sites of metastases are the lungs; however, other sites of spread have been documented. These tumors by definition have no malignant features on histology and tend to be estrogen and progesterone positive. We present a middle-aged woman who was incidentally found to have multiple pulmonary nodules and a mass on her sternum after she was involved in a motor vehicle accident. She had a history of uterine leiomyoma and had undergone a hysterectomy ten years prior to the accident. Biopsies were performed of the lung nodules and sternum mass and compared to her hysterectomy specimen, and they were identical, and hence, she was diagnosed with BML. Due to the growing tumor of her sternum, she was started on tamoxifen with stability of her tumors. These tumors, since they are benign, tend to have an indolent course. However, in the instances that treatment is warranted, options include surgery or antiestrogen therapy. We will be discussing the pathogenesis, histological findings, and treatment options of this rare condition. Our case is unique because BML in general do not tend to spread to multiple organs and tend to be limited to one site of disease.