Pelvic Intravascular Leiomyomatosis Associated With Benign Pulmonary Metastasizing Leiomyoma: Clinicopathologic, Clonality, and Copy Number Variance Analysis

Diagnostic experience of intravenous leiomyomatosis with emphasis on conventional ultrasonography imaging: a single-center study

Objective

Intravenous leiomyomatosis (IVL) is a rare and aggressive tumor type that has the potential to extend into the inferior vena cava (IVC) and is susceptible to be misdiagnosed and neglected. Despite its clinical significance, there is a paucity of research that has focused on the specific manifestations of IVL on ultrasonography. Therefore, this study aims to systematically analyze the specific ultrasound features of IVL and augment its diagnostic accuracy.

Materials and method

Prospective inclusion was granted to patients admitted to our hospital between December 2016 and March 2021 for an IVC-occupying lesion. Multi-modal ultrasonography, encompassing gray-scale and color Doppler, was conducted. Lesions were categorized as IVL or non-IVL based on pathological or follow-up data. Two ultrasound sonographers with over 5 years of experience read and recorded ultrasound data for all lesions, which were subsequently comparatively analyzed to identify specific signs of IVL.

Results

A total of 284 patients diagnosed with IVC-occupying lesions were included in the study. The lesion types comprised of IVL (n=67, 23.6%), IVC thrombus (n=135, 47.5%), tumor thrombus of renal carcinoma involving the IVC (n=35, 12.4%), tumor thrombus of liver carcinoma involving the IVC (n=24, 8.5%), leiomyosarcoma of the IVC (n=14, 4.9%), and tumor thrombus of adrenocortical adenocarcinoma (n=9, 4.1%). The presence of "sieve hole" and "multi-track" signs was observed in 20 IVL lesions under the grey-scale modality, while both signs were absent in the non-IVL group (P<0.01). The study found no statistically significant differences in the presentation of "sieve hole" and "multi-track" signs under the grey-scale and color Doppler modalities in cases of intravascular lithotripsy (IVL) (P>0.05). Using these two signs as diagnostic criteria for IVL, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), miss rate, misdiagnosis rate, and accuracy were determined to be 29.9%, 100%, 100%, 82.2%, 70.1%, 0, and 83.5%, respectively (AUC ROC=0.649; 95%CI: 0.537-0.761).

Conclusion

IVL exhibits distinct ultrasound presentations, including "sieve hole" and "multi-track" signs, which demonstrate high specificity and accuracy as diagnostic indicators. Furthermore, these signs are corroborated by pathological evidence and effectively distinguish IVL from other lesions occupying the IVC.

Benign Metastasizing Leiomyomatosis to the Skin and Lungs, Intravenous Leiomyomatosis, and Leiomyomatosis Peritonealis Disseminata: A Series of Five Cases

Benign metastasizing leiomyomatosis (BML) is a rare disease that typically occurs in women with a history of uterine leiomyomatosis. Benign metastasizing leiomyomatosis occurs more frequently in the lungs but may also develop in other organs and tissues. Other unusual variants of extra-uterine leiomyomatosis include intravenous leiomyomatosis (IVL) and leiomyomatosis peritonealis disseminata (LPD). In this article, three cases of BML are presented. One case, in a premenopausal woman, presented cutaneous metastases. We also present a case of IVL and a case of LPD, which occurred in postmenopausal women. Given the rarity of BML, IVL, and LPD, the authors reviewed the literature and herein discuss the implications for treatment in all five cases. Evidence for treating BML, IVL, and LPD is still scarce, and data available from our series and other small series seem to point to the patient’s hormonal status playing a fundamental part in the treatment plan. Furthermore, a collecting bag when performing excision of uterine leiomyomas may help avoid the potential spreading of leiomyomatosis. Hysterectomized patients with chronic cough, frequent respiratory infections, abdominal discomfort, right heart failure, or non-specific symptoms should be actively screened for BML, IVL, and LPD. Treatment should be individualized according to each patient’s hormonal status and desires.

Computed tomography evaluation of extensive intravenous angioleiomyoma: a case report

Background

Uterine angioleiomyoma is a rare variant of leiomyoma, and the main therapy is complete surgery. This study introduces the benefit of three-dimensional computed tomography reconstruction for preoperative preparation.

Case presentation

A 50-year-old woman presented because of chest distress after activity, with worsening symptoms. After examination, the final diagnosis was uterine angioleiomyoma. The tumour originated in the uterus; grew into the right iliac vein; coursed along the iliac vein, inferior vena cava, and right atrium; and finally invaded the right ventricle. To best complete the surgery, a multidisciplinary surgery was selected. Before the surgery, a three-dimensional computed tomography reconstruction model was created to assess the tumour status, and this model enabled the surgery to be completed successfully.

Conclusion

Three-dimensional computed tomography reconstruction is of great significance for the preoperative diagnosis of uterine angioleiomyoma and the formulation of surgical treatment plans. Based on its vivid images, surgeons can perform operations more effectively and safely.

Uterine intravenous leiomyomatosis with an isolated large metastasis to the right atrium: a case report

Background

An intravenous leiomyomatosis is a special type of uterine leiomyoma characterized by the formation of benign leiomyomatous tissue within the vascular wall. Although histologically benign, intracardiac metastasis can lead to circulatory failure, and death, if untreated. Herein, we report on a case of a uterine intravenous leiomyomatosis with an isolated large adherent metastasis in the right atrium of the heart.

Case Presentation

A 52-year-old Japanese woman sought medical attention at our hospital for lower abdominal pain. A 27-cm uterine mass was detected on clinical imaging, with a 78 × 47-mm mass in the right atrium detected on preoperative echocardiography. Intracardiac mass resection and tricuspid annuloplasty were performed as the first-stage surgery. The pedicle of the tumor was adherent to the wall of the atrium. On histological examination, the tumor was found to consist of spindle-shaped cells with eosinophilic cytoplasm, without atypia, but with a myxoid change, and rich microvascularization of the pedicle. Total abdominal hysterectomy was performed as the second-stage surgery, with confirmation of the diagnosis as uterine intravenous leiomyomatosis with an isolated metastasic lesion to the right atrium. There has been no evidence of tumor recurrence in the 15 months since surgery.

Conclusion

We report a unique case in which a large right atrial leiomyoma was identified following a uterine intravenous leiomyomatosis. Our case exemplifies that intravenous leiomyomatosis metastatic tumors have the potential to grow via their vascularization.

EP4 and Class III β-Tubulin Expression in Uterine Smooth Muscle Tumors: Implications for Prognosis and Treatment

The microtubule-stabilizing agent docetaxel in combination with gemcitabine represents one of the most effective regimens against the aggressive gynecologic tumor leiomyosarcoma (LMS). Upregulation of class III β-tubulin has previously been shown to confer taxane resistance in a variety of human cancers. Prostaglandin E₂ receptor EP4 is linked to progression of a variety of human cancers and may represent a novel target for tumor inhibition in LMS. We evaluated the hypotheses that EP4 and class III β-tubulin have increased expression in LMS in comparison to normal myometrium or benign tumors and that expression of class III β-tubulin correlates with resistance to taxanes and poor clinical outcome. Gene expression was examined using TCGA data and correlated with clinicopathologic outcome which demonstrated that class III β-tubulin is more highly expressed in more aggressive sarcomas with EP4 being widely expressed in all subtypes of sarcoma. Immunohistochemistry for EP4 and class III β-tubulin was performed on patients with LMS, leiomyomatosis/STUMP, leiomyoma, and normal myometrium. Expression of EP4 and class III β-tubulin were characterized for cell lines SK-UT-1, SK-UT-1B, and PHM-41 and these cell lines were treated with docetaxel alone and in combination with EP4 inhibitors. In taxane-resistant cell lines that overexpress class III β-tubulin and EP4, treatment with EP4 inhibitor resulted in at least 2-fold sensitization to docetaxel. Expression of class III β-tubulin and EP4 in LMS may identify patients at risk of resistance to standard chemotherapies and candidates for augmentation of therapy through EP4 inhibition.

[Extra uterine leiomyomatosis: Review of the literature]

Extra-uterine leiomyomatosis is a rare pathology defined by the presence of benign smooth uterine muscle cells in unusual localizations, including different entities. It mainly affects premenopausal women with a medical history of uterine myoma with or without surgical treatment. Three main types are discribed: intraveinous leiomyomatosis, benign metastatisizing leiomyoma and leiomyomatosis peritonealis disseminata. The diagnosis may be complex with many differential diagnosis, and relies on histology. The treatment depends on multiple factors such as age, localization, size, symptoms and associated comorbidities. It is based on surgical resection and hormonal privation, surgical (adnexectomy) or medical (hormonotherapy). There is a high risk of recurrence. Some malignant evolutions have been reported, mostly leiomyosarcoma following peritoneal disseminated leiomyomatosis. Long term follow-up of these patients is mandatory. A particular manifestation of extra-uterine leiomyomatosis is the hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome. It is an autosomal dominant disorder which confers an increased risk of cutaneous and uterine leiomyomas and renal cell cancer, with a poor prognosis due to the urologic tumor.

The fusion landscape of hepatocellular carcinoma

Most cases of hepatocellular carcinoma (HCC) are already advanced at the time of diagnosis, which limits treatment options. Challenges in early‐stage diagnosis may be due to the genetic complexity of HCC. Gene fusion plays a critical function in tumorigenesis and cancer progression in multiple cancers, yet the identities of fusion genes as potential diagnostic markers in HCC have not been investigated. Here, we employed STAR‐Fusion and identified 43 recurrent fusion events in our own and four public RNA‐seq datasets. We identified 2354 different gene fusions in two hepatitis B virus (HBV)‐HCC patients. Validation analysis against the four RNA‐seq datasets revealed that only 1.8% (43/2354) were recurrent fusions. Comparison with the four fusion databases demonstrated that 19 recurrent fusions were not previously annotated to diseases and three were annotated as disease‐related fusion events. Finally, we validated six of the novel fusion events, including RP11‐476K15.1‐CTD‐2015H3.2, by RT‐PCR and Sanger sequencing of 14 pairs of HBV‐related HCC samples. In summary, our study provides new insights into gene fusions in HCC and may contribute to the development of anti‐HCC therapy.

Identification of genomic copy number variations in lung benign metastasizing leiomyomatosis

OBJECTIVES

Lung metastasizing leiomyomatosis (LML) is an infrequently diagnosed pathology developed after sexual maturation, commonly preceded by uterine myomas. Symptoms can include difficulties to breathe, cough, dyspnea and pain, because of mechanical obstruction exerted by expanding local growing leiomyomas. Lung leiomyomas are normally detected by imaging studies, but nowadays the precise diagnosis demands histological characterization of biopsies obtained from the affected tissues. The purpose of the present study was to determine the presence of genomic alterations in circulating cells of LML.

METHODS

Immunohistochemical characterization of a lung biopsy extracted by thoracoscopy was performed. Pathologic proliferative smooth muscle cells were observed in a major lung metastasizing nodule, with a growing pattern similar to a uterine myoma. The presence of cellular linages different to smooth muscle cells was discarded by testing the presence of a battery of molecular markers. Also, a normal karyotype was determine by GTG-banding cytogenetic study, but a high density microarray analysis revealed six submicroscopic chromosomal regions displaying genomic abnormalities: microduplications were detected on chromosomes 4, 14, 17 and 22; and microdeletions on chromosomes 8 and 10.

CONCLUSION

This study remarks the relevance of submicroscopic chromosomal analysis of unusual pathologic conditions such as Benign Metastasizing Leiomyomatosis. This propitiate a better understanding of the molecular basis on the development of the pathology, in order to reckon on minimally invasive diagnostic methods, and to design appropriate treatments.

[Intravascular leiomyomatosis with intracardiac extension]

Intravascular leiomyomatosis is a rare condition characterized by histologically benign smooth muscle cell growth within the uterine veins and inferior vena cava and, rarely, into the right chambers of the heart. A 39-year-old female with a history of hysterectomy for uterine leiomyoma was admitted for lower limb oedema and progressive dyspnea of 5 months' duration. Transthoracic echocardiography and contrast-enhanced computed tomography showed a large mass extending through the inferior vena cava into the right chambers of the heart. As there was a suspicion of an intravenous thrombus, the patient underwent surgical resection. The histopathology of the resected mass led to a diagnosis of Intravascular leiomyomatosis with intracardiac extension.

Multiclonal tumor origin: Evidence and implications

An accurate understanding of the clonal origins of tumors is critical for designing effective strategies to treat or prevent cancer and for guiding the field of cancer risk assessment. The intent of this review is to summarize evidence of multiclonal tumor origin and, thereby, contest the commonly held assumption of monoclonal tumor origin. This review describes relevant studies of X chromosome inactivation, analyses of tumor heterogeneity using other markers, single cell sequencing, and lineage tracing studies in aggregation chimeras and engineered rodent models. Methods for investigating tumor clonality have an inherent bias against detecting multiclonality. Despite this, multiclonality has been observed within all tumor stages and within 53 different types of tumors. For myeloid tumors, monoclonal tumor origin may be the predominant path to cancer and a monoclonal tumor origin cannot be ruled out for a fraction of other cancer types. Nevertheless, a large body of evidence supports the conclusion that most cancers are multiclonal in origin. Cooperation between different cell types and between clones of cells carrying different genetic and/or epigenetic lesions is discussed, along with how polyclonal tumor origin can be integrated with current perspectives on the genesis of tumors. In order to develop biologically sound and useful approaches to cancer risk assessment and precision medicine, mathematical models of carcinogenesis are needed, which incorporate multiclonal tumor origin and the contributions of spontaneous mutations in conjunction with the selective advantages conferred by particular mutations and combinations of mutations. Adherence to the idea that a growth must develop from a single progenitor cell to be considered neoplastic has outlived its usefulness. Moving forward, explicit examination of tumor clonality, using advanced tools, like lineage tracing models, will provide a strong foundation for future advances in clinical oncology and better training for the next generation of oncologists and pathologists.

Perivascular Leiomyomatosis: A Unique Case Report

There are 3 histologically benign smooth muscle neoplasms that have unusual growth patterns. These include intravascular leiomyomatosis, benign metastasizing leiomyoma, and leiomyomatosis peritonealis desseminata. We report a unique case of perivascular leiomyomatosis. The tumor showed multiple nodules of benign smooth muscle with some of the nodules closely associated with the periphery of the medial muscle layer of venous channels. All the neoplastic nodules were located on the outer surface of venous channels, thus precluding a diagnosis of intravascular leiomyomatosis. To the best of our knowledge, this is the first documentation of such an entity.

Massively parallel sequencing and genome-wide copy number analysis revealed a clonal relationship in benign metastasizing leiomyoma

Benign metastasizing leiomyoma (BML) is a rare disease entity typically presenting as multiple extrauterine leiomyomas associated with a uterine leiomyoma. It has been hypothesized that the extrauterine leiomyomata represent distant metastasis of the uterine leiomyoma. To date, the only molecular evidence supporting this hypothesis was derived from clonality analyses based on X-chromosome inactivation assays. Here, we sought to address this issue by examining paired specimens of synchronous pulmonary and uterine leiomyomata from three patients using targeted massively parallel sequencing and molecular inversion probe array analysis for detecting somatic mutations and copy number aberrations. We detected identical non-hot-spot somatic mutations and similar patterns of copy number aberrations (CNAs) in paired pulmonary and uterine leiomyomata from two patients, indicating the clonal relationship between pulmonary and uterine leiomyomata. In addition to loss of chromosome 22q found in the literature, we identified additional recurrent CNAs including losses of chromosome 3q and 11q. In conclusion, our findings of the clonal relationship between synchronous pulmonary and uterine leiomyomas support the hypothesis that BML represents a condition wherein a uterine leiomyoma disseminates to distant extrauterine locations.

Deep sequencing reveals the molecular pathology characteristics between primary uterine leiomyoma and pulmonary benign metastasizing leiomyoma

PURPOSE

Pulmonary benign metastasizing leiomyoma (PBML), a rare condition of smooth muscle tumor, originates from women with a history of uterine leiomyoma (LM). Numerous genetic studies of uterine LM have been reported; however, there are few cytogenetic and molecular descriptions of PBML. Therefore, molecular subtyping is necessary to understand the pathogenesis of metastasizing sites.

METHODS

Driver gene exon-capture sequencing was performed on one patient's peripheral blood, paraffin samples from primary uterine LM, and lung metastasizing leiomyoma 8 years later.

RESULTS

The results showed that the same missense mutations of BLMH, LRP2, MED12, SMAD2, and UGT1A8 were concurrently mutated in the primary uterine LM and the PBML. Moreover, a splice mutation of PTEN (c.492+1G>A) was uniquely identified in the lung metastasis of the patient.

CONCLUSION

This study indicates that the metastatic lung lesions were derived from the same malignant cell clone of uterine LMs and later acquired the novel driver mutations in the evolution of the tumor. In addition, driver gene sequencing can discriminate somatic driver mutations as biological indicators of potential malignant leiomyoma and can identify pathogenic variation driver mutations, which could be used for individualized therapy.

Recurrent benign leiomyomas after total abdominal hysterectomy. Rich or poor estrogenic environment may lead to their recurrence?

INTRODUCTION

Benign metastasizing leiomyomas represent benign lesions consisted by leiomatosous tissue and could be observed in positions away from their usual localization, the human uterus. They commonly affect women that have undergone total hysterectomy. Approximately 100 similar cases have been reported in the literature, so the case we present is rare and reviewing the literature and needs to be reported.

PRESENTATION OF CASE

We report a case of a 55 year old Greek woman, gravida five and para three, who attended our unit 3 years ago complaining of occasionally lower abdominal pain and irritation the last months. Fourteen years ago she underwent abdominal hysterectomy and left salpingo-oophorectomy due to a 13 cm uterine leiomyoma. In the meantime she underwent two surgical procedures for recurrent benign leiomyomas.

DISCUSSION

When patient was admitted at this time, clinical examination revealed a palpable mass of 5 cm. The transvaginal ultrasonography revealed 3 masses in the lower pelvis of unknown origin. The patient underwent a new laparotomy revealing three masses of benign leiomyomas with low mitotic activity.

CONCLUSION

Our case supports the recurrent appearance of leiomyomas in pelvis after total abdominal hysterectomy and is one of few reports in literature where the tumors appear in the same patient both in estrogen rich and estrogen poor environment. Additionally, we show the importance of transvaginal ultrasonography and 3 dimensional power Doppler in the differential diagnosis of pelvic masses. Thus, transvaginal ultrasonography seems to be a pivotal tool for the diagnosis and follow up of these challenging lesions.

Whole exome sequencing of benign pulmonary metastasizing leiomyoma reveals mutation in the BMP8B gene

Background

Benign metastasizing leiomyoma (BML) is an orphan neoplasm commonly characterized by pulmonary metastases consisting of smooth muscle cells. Patients with BML have usually a current or previous uterine leiomyoma, which is therefore suggested to be the most probable source of this tumour. The purpose of this case report was to determine the possible genetic grounds for pulmonary BML.

Case presentation

We present a case report in an asymptomatic 44-year-old female patient, who has developed uterine leiomyoma with subsequent pulmonary BML. Whole exome sequencing (WES) was used to detect somatic mutations in BML lesion. Somatic single nucleotide mutations were identified by comparing the WES data between the pulmonary metastasis and blood sample of the same BML patient. One heterozygous somatic mutation was selected for validation by Sanger sequencing. Clonality of the pulmonary metastasis and uterine leiomyoma was assessed by X-chromosome inactivation assay.

Conclusions

We describe a potentially deleterious somatic heterozygous mutation in bone morphogenetic protein 8B (BMP8B) gene (c.1139A > G, Tyr380Cys) that was identified in the pulmonary metastasis and was absent from blood and uterine leiomyoma, and may play a facilitating role in the metastasizing of BML. The clonality assay confirmed a skewed pattern of X-chromosome inactivation, suggesting monoclonal origin of the pulmonary metastases.

Electronic supplementary material

The online version of this article (10.1186/s12881-018-0537-5) contains supplementary material, which is available to authorized users.

Successful en bloc venous resection with reconstruction and subsequent radiotherapy for 2 consecutive recurrences of intravenous leiomyoma--a case report

BACKGROUND

Intravenous leiomyomas are a rare variant of uterine leiomyoma. Although histologically benign, these tumors are associated with a poor prognosis due to propensity for metastasis, high recurrence rate, difficulty of obtaining complete resection, and frequent extension into and along major veins.

CASE PRESENTATION

We describe a 43-year-old patient initially presenting with lower abdominal pain. Clinical examination revealed a large right pelvic mass that was shown by computed tomography (CT) to surround the right external iliac vein, right common iliac vein and distal inferior vena cava. The patient had a history of total abdominal hysterectomy with bilateral ovarian cystectomies for uterine leiomyoma approximately 3 years prior to her presentation. Her past surgical history also included removal of an ovarian endometriosis cyst and right hydrosalpinx. The patient underwent an exploratory laparotomy. Operative findings included complete occlusion of the right iliac vessels and distal vena cava by a large tumor that filled the pelvis and extended to the level of the right kidney. The mass was resected en bloc with the involved veins and synthetic vascular grafts were placed. This highly technical procedure was complicated by hemorrhage requiring a total of 32 units of red blood cells and 2.0 L of plasma. Pathologic examination confirmed intravenous leiomyoma. On Immunohistochemical staining, the tumor cells were positive for CD32, CD34, Vimentin and smooth muscle actin. Eight months after this procedure, the patient again presented with an abdominal mass. She was diagnosed with a pelvic recurrence and noted to have intravascular extension into the left iliac vein and inferior vena cava. For this tumor she underwent radiation treatment with three-dimensional conformal radiation therapy (total dose 4500 cGy). The tumor gradually decreased in size during follow-up and became undetectable by CT.

CONCLUSIONS

Surgical excision is the mainstay of treatment of intravenous leiomyoma. Radiation therapy may be an effective alternative in patients with unresectable disease or poor surgical candidates.

Vascular invasion in uterine sarcomas and its significance. A multi-institutional study

Although metastases and high-mortality are frequent in high-grade endometrial sarcomas (HGSs), these findings are less commonly seen in low-grade endometrial stromal sarcomas (LGESSs), even in cases with lymphovascular invasion (LVI). We hypothesized that the "bulging plugs" of tumor characteristic of LVI in LGESS are fundamentally different from LVI seen in HGS. We reviewed 70 uterine sarcomas: 42 HGSs (high-grade endometrial stromal sarcomas, undifferentiated uterine sarcoma, and leiomyosarcoma) and 28 LGESSs. All cases had LVI documented on the histologic slides. Immunostains for CD31, ERG, and D2-40 were performed. LGESS harbored cohesive intravascular tumor foci with direct communication from the main tumor and attached to the vessel wall. The intravascular foci included tumor cells and small arteriole-type vessels and were surrounded by a thin fibrous band. Vascular markers confirmed the LVI and highlighted positively stained endothelial cells separating intravascular tumor foci from the blood itself. In contrast, intravascular tumor foci in HGS were composed of discohesive cells clusters, lacking the features described in LGESS. Only 8 (30.8%) patients with LGESS had recurrence/metastases (6 with lung metastasis); only 1 patient died of disease. Thirty (77%) patients with HGS had recurrence/metastases, 27 (69%) patients had lung metastases, and 22 (56.4%) patients died of disease. We propose that in most LGESSs, LVI represents vascular intrusion; manipulation or trauma is potentially responsible for tumor cell detachment into the circulation increasing the chances of recurrence/metastases. Classic LVI features were identified in HGS. This important distinction may allow for better management of patients and avoid unnecessary treatment in LGESS, reducing morbidity.

Benign Metastasizing Leiomyomas to the Lungs: An Institutional Case Series and a Review of the Recent Literature

BACKGROUND

Benign metastasizing leiomyomas (BMLs) represent the extrauterine spread of a benign uterine process. Pulmonary BMLs are the most common example of distant spread of uterine leiomyomas and are usually found incidentally in premenopausal women. The rarity of BMLs accounts for the limited literature that currently exists regarding their underlying pathophysiology, disease course, and management.

METHODS

A retrospective analysis was performed of all BML cases diagnosed and managed at Brigham and Women's Hospital during a 22-year period. The demographic and clinical characteristics of these patients were compared with a PubMed-derived cohort of BML cases reported since 2006.

RESULTS

Benign metastasizing leiomyoma tumors were identified in 10 Brigham and Women's Hospital patients, whereas 57 cases were reported in the literature. The average age at diagnosis was 54.1 and 46.7 years, respectively. Mean interval time from a pertinent gynecologic procedure to BML diagnosis was 23 years at Brigham and Women's Hospital. All patients demonstrated positivity for actin, desmin, and estrogen/progesterone receptors, confirming the diagnosis of uterine leiomyomas. Management primarily consisted of diagnostic resection with subsequent observation with or without hormonal suppression for residual pulmonary nodules. Progression of residual BMLs was noticed in 30% and 8.3% of Brigham and Women's Hospital and literature patients, respectively, when follow-up was reported. One patient in our series required further surgical management.

CONCLUSIONS

Benign metastasizing leiomyomas are a rare cause of pulmonary nodules. They likely represent a clonal spread of uterine leiomyomas to the lungs. Management includes pathologic diagnosis with long-term surveillance with or without hormonal manipulation.