Case of concurrent benign metastasizing leiomyoma in the lung and retroperitoneum, with a focus on its etiology

Unexpected Origin of Lung Metastases: Rare Colon Leiomyosarcoma Detected by 18F-FDG PET/CT

ABSTRACT

A 49-year-old woman was referred to our hospital due to suspected lung metastases for 1 month. She had a history of thyroid micropapillary carcinoma and uterine leiomyomas. An 18F-FDG PET/CT scan, which was performed to search the source of the presumed metastasis of the disease, showed multiple lung metastases and 2 18F-FDG-avid foci in the thyroid and colon. Biopsy of lung and resection of colon lesions were then performed, and the disease was finally identified to be rare primary colon leiomyosarcoma with multiple lung metastases.

Current management of benign retroperitoneal tumors

Benign retroperitoneal tumors (BRT) represent a rare group of heterogeneous diseases. The literature lacks high-quality evidence about the optimal management of BRT, and most of the information available takes the form of case reports or case series. The aim of this review is to provide an overview of current management strategies for adult patients with BRT. A literature search using PubMed indexed articles was conducted and BRT were classified into five different biological subgroups: 1) lipomatous tumors, 2) smooth muscle tumors, 3) peripheral nerve sheath tumors, 4) myofibroblastic tumors, and 5) others. Tumors that are primarily pelvic in origin were excluded. Despite the significant heterogeneity of the disease, several generic considerations have emerged and can be applied to the management of BRT. Specifically, the risk of misdiagnosing a BRT with another pathology such as retroperitoneal sarcoma is notable. When encountered, suspected BRT should therefore be referred to a specialized sarcoma center. Multidisciplinary tumor boards, present at these centers, have a pivotal role in managing BRT. The decision of whether to offer surgery, nonsurgical treatment or a "watch-and-wait" approach should be made after multidisciplinary discussion, depending on tumor histology. Moving forward, collaborative research efforts dedicated to BRT remain crucial in gathering evidence and knowledge to further optimize patient care.

The Heart as a Site of Metastasis of Benign Metastasizing Leiomyoma: Case Report and Review of the Literature

Uterine leiomyomas are the most common gynecological tumors in premenopausal women. While the lung is the most common extrauterine organ afflicted, benign metastasizing leiomyomas (BML) of the heart are rarities. We report an incidental finding of a cardiac mass in a 36-year-old woman who presented to the Emergency Department after a motor vehicle accident. CT scan of the chest revealed 2 well-circumscribed pulmonary nodules and a filling defect in the right ventricle. Echocardiogram showed a 4 cm mass attached to the right ventricular (RV) septum. The cardiac tumor was resected and showed benign histologic features. Immunohistochemical staining was positive for smooth muscle α-actin and desmin, as well as estrogen and progesterone receptors, consistent with the diagnosis of uterine leiomyoma.

Unexpected pulmonary tumor: metastasis from a benign uterine leiomyoma in a post-menopausal woman: a case report

BACKGROUND

The occurrence of lung metastasis from benign uterine leiomyomas is rarely reported especially in post menopausal women. The pathogenesis of these metastatic benign tumors still remains a subject of various speculations.

CASE PRESENTATION

A 57-year-old woman presented with a chronic cough and dyspnea. She had undergone 8 years previously, hysterectomy for benign leiomyomas. A chest computed tomography scan showed a 4 cm solitary nodular parenchymal tumor that increased in size after 12 months. The histological analysis of the biopsy from this nodule showed a benign tumor with regular spindle cells disposed in intersected fascicles. At immunohistochemical analysis, the tumor cells were positive for smooth muscle markers and oestrogen-progesterone receptors with a low mitotic index assessed by Ki-67. These features were consistent with a benign metastasizing uterine leiomyoma. At the multidisciplinary meeting, prescription of an aromatase inhibitor has been decided for the patient.

CONCLUSIONS

Benign metastasizing uterine leiomyomas of the lung are very rare tumors. Although extremely rare in post menopausal women, their diagnosis should be considered in symptomatic patients with a history of hysterectomy for leiomyomas.

Identification of uterine leiomyoma-specific marker genes based on DNA methylation and their clinical application

Differential diagnosis of uterine leiomyomas and leiomyosarcomas is needed to determine whether the uterus can be retained. Therefore, biomarkers for uterine leiomyomas, and reliable and objective diagnostic methods have been desired besides the pathological diagnosis. In the present study, we identified 12 genes specific to uterine leiomyomas based on DNA methylation. Using these marker genes specific to uterine leiomyomas, we established a hierarchical clustering system based on the DNA methylation level of the marker genes, which could completely differentiate between uterine leiomyomas and normal myometrium. Furthermore, our hierarchical clustering system completely discriminated uterine cancers and differentiated between uterine leiomyosarcomas and leiomyomas with more than 70% accuracy. In conclusion, this study identified DNA methylation-based marker genes specific to uterine leiomyomas, and our hierarchical clustering system using these marker genes was useful for differential diagnosis of uterine leiomyomas and leiomyosarcomas.