On the so-called metastasizing leiomyoma

Uterine Benign-Appearing Smooth Muscle Tumor « Metastatic » to the Lungs: A Case Report

A case of pulmonary fibroleiomyomatosis secondary to a uterine « metastasizing » leiomyoma, with aspects of vascular invasion, is reported. Although we cannot exclude the existence of primitive pulmonary forms, which we do not consider to be of a hamartomatous nature, we believe that a careful examination of the uterus for the presence of angioinvasive leiomyoma is mandatory.

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.

Distinctive cytogenetic profile in benign metastasizing leiomyoma: pathogenetic implications

"Benign metastasizing leiomyoma" is the terminology used to describe a controversial entity characterized by a proliferation of bland-appearing smooth muscle in lung or abdominopelvic lymph nodes. In this report, we describe 5 cases of pulmonary-based smooth muscle tumors that are clinically and histologically consistent with this entity, and in which we identified consistent chromosomal aberrations (19q and 22q terminal deletion in all cases). This cytogenetic profile is found in approximately 3% of uterine leiomyoma, but has not been described in other types of benign or malignant neoplasia. These findings suggest that the nodular pulmonary smooth muscle proliferations termed "benign metastasizing leiomyoma," are a genetically distinct entity, which likely originate from a biologically distinctive subset of uterine leiomyoma.

Unusual primary lung tumors: a radiologic-pathologic overview

Although the great majority of lung carcinomas are histologically characterized as adenocarcinoma, squamous cell carcinoma, large cell undifferentiated carcinoma, or small cell carcinoma, a variety of rare benign and malignant lung tumors may sporadically affect the lung. Several nonneoplastic tumorlike lesions are seen infrequently but are also part of the differential diagnosis for lung masses. Conventional radiographic findings, although of limited value in the diagnosis of these entities, should be examined carefully when lung tumors are suspected. Computed tomography (CT) is well suited for making a definitive diagnosis of some disease processes. CT helps determine the location and features of the lesions and depicts associated findings to help document the extent of disease. The differential diagnosis can be narrowed when there are typical CT features (eg, the presence of fat in lipoid pneumonia). Although unusual primary lung tumors are difficult to diagnose on the basis of imaging findings alone because such findings are nonspecific in the majority of cases, cross-sectional imaging can play an important role in the diagnostic work-up of these unusual tumors by delineating their extent and directing the radiologist or bronchoscopist to the appropriate biopsy site.

Intravenous leiomyomatosis of the uterus with multiple pulmonary metastases associated with large bullae-like cyst formation

We present a case of uterine intravenous leiomyomatosis associated with multiple pulmonary metastases with bullae-like cystic change. A 53-year-old woman who had undergone hysterectomy 5 years previously underwent an operation for multiple pulmonary nodules with bullae formation. After resection of several large bullae, a subsequent extirpation of the pulmonary nodules was performed, and a pathological examination showed multiple leiomyomatous nodules with occasional cystic change. A review of the previous slides of the uterus and immunohistochemical analysis of the proliferating ability using anti-Ki-67 and anti-proliferating cell nuclear antigen (PCNA) antibodies were performed. Proliferating cells of the uterus had very few mitotic figures for their high cellularity, and the labeling indices of Ki-67 and PCNA indicated very low levels in both uterine neoplasm and pulmonary nodules. From these findings, an intravenous leiomyomatosis associated with multiple pulmonary metastases was diagnosed.

Metastasizing uterine leiomyoma. A case with cardiac and pulmonary metastasis

A case of histologically benign cardiac and pulmonary metastases from a uterine leiomyoma in a 45-year-old woman is reported. The solitary cardiac tumor consisted of five lobules with a stalk attached to the anterior papillary muscle of the right ventricle, which occupied the right ventricular cavity and almost completely obstructed the pulmonary main trunk in the systolic cycle. Multiple small nodules were found throughout both lungs. The cardiac tumor was resected at open heart surgery and open lung biopsy of the pulmonary lesion was simultaneously performed. Both of them were histologically identical to the apparently histologically benign uterine leiomyoma which had been resected five years previously. Based on the clinical and laboratory findings, it is postulated that antegrade metastases via the venous system resulted in the cardiac metastasis from the uterine leiomyoma and the secondary pulmonary metastasis from the cardiac tumor. In contrast to the light microscopic findings, ultrastructural examination suggested the possibility of malignancy associated with the presence of immature smooth muscle cells. This is the first reported case of a so-called benign metastasizing leiomyoma occurring in the heart.

Immunohistological detection of estrogen and progesterone receptors in multiple and well differentiated leiomyomatous lung tumors in women with uterine leiomyomas (so-called benign metastasizing leiomyomas). A report on 5 cases

Seventy-four cases of so-called "benign metastasizing uterine leiomyomata" are reported in the literature. In these cases, well differentiated, leiomyomatous lung tumors developed, usually after a period of several years. Histologically, these tumors appear to be benign. We report on five more such cases in which we investigated the contents of estrogen and progesterone receptors in the pulmonary tumors by immunohistological procedures. All the lung tumors exhibited a high content of progesterone receptors, and in 4 out of the 5 cases a high estrogen receptor content was also found. Modern immunohistological techniques permit the investigation of routinely fixed tissue blocks, and it is thus recommended that the contents of these hormone receptors should be determined in well differentiated, leiomyomatous lung tumors from women. This would both provide information on the pathogenesis of these tumors and establish a basis for possible later institution of hormone treatment. It is likely that the majority of these lung tumors are in fact metastases of extremely well differentiated leiomyosarcomas of the uterus. The possibility that lung tumors of this type may constitute a small group that develop in situ as hormone-sensitive proliferations cannot, however, be fully excluded.

Unusual computed tomographic manifestations of benign metastasizing leiomyomas as cavitary nodular lesions or interstitial lung disease

The unusual computed tomographic manifestations of benign metastasizing leiomyomas diagnosed in two patients 3 1/2 and 6 years after hysterectomy for uterine fibroids are described. One showed multiple pulmonary nodules with a round or irregular air-filled cavity representing obstructive emphysema. The other showed interstitial lung disease with tumor cells spreading along alveolar septa, the vascular wall, and the bronchial tree. We consider such metastasizing tumors as low-grade leiomyosarcomas.

Leiomyomatosis with vascular invasion. A unified pathogenesis regarding leiomyoma with vascular microinvasion, benign metastasizing leiomyoma and intravenous leiomyomatosis

Three uterine leiomyomas with vascular invasion (LWVI), two of which were associated with pulmonary leiomyomatous nodules, and a case of intravenous leiomyomatosis (IVL) invading the vena cava and extending to the right atrium, are described. Despite their histological benignity, these lesions have a strong tendency to metastasize and are closely related to the so-called benign metastasizing leiomyoma (BML). From a clinical point of view, the pulmonary nodules of LWVI are stable or slowly-growing. The IVL was a "worm-like" tumour that presented as a cardiac mass. On the basis of their histological and immunohistological features, a unified histogenetic view of LWVI, IVL and BML of the uterus is proposed. LWVI and BML may be the same pathological entity and microscopic vascular invasion may represent the metastatic mechanism of BML. Alternatively, LWVI may be the initial stage of IVL. In rare instances, IVL may be associated with distant parenchymal (pulmonary) metastases. LWVI seems to be the precursor of both BML and IVL.

Metastatic uterine leiomyosarcoma in association with recurrent lung abscess

A case of metastatic uterine leiomyosarcoma complicated by recurrent lung abscesses is described.

Leiomyoma of the uterus with multiple extrauterine smooth muscle tumors: a case report suggesting multifocal origin

A 17-year-old woman underwent hysterectomy for removal of a "mitotically active" (six to seven mitoses per 10 high-power fields) yet otherwise benign-appearing cellular smooth muscle tumor. Eleven years later, she developed multiple histologically benign smooth muscle tumors in the posterior mediastinum, deep soft tissues of the neck, paravertebral region, incisional scar, and mesentery. The distribution and histologic appearance of the tumors, as well as the protracted clinical course, suggest multifocal origin rather than widespread metastases from a low-grade uterine leiomyosarcoma. This case raises the possibility that some similar cases reported as so-called benign metastasizing leiomyoma may be more satisfactorily explained by the concept of multifocality.

Metastasizing leiomyoma of the uterus

This report describes a patient who underwent a subtotal hysterectomy 6 years ago for fibroids. She re-presented recently with lung metastases and a pelvic mass. Macroscopic appearances at laparotomy suggested a leiomyosarcoma of the uterine stump, but histological appearances suggested the patient was suffering from the rare condition 'metastasizing leiomyoma'. Subsequent response to hormone manipulation supported the latter diagnosis.

Benign metastasizing leiomyoma

The cases of 2 patients with benign metastasizing leiomyofibroma are reviewed. Although extremely rare both in our experience and in the literature, benign metastasizing leiomyofibroma is an important differential diagnosis in young women seen with multiple lung nodules. Our patients underwent staged thoracotomies for diagnosis and treatment, and have experienced no evidence of recurrence over a six-year period.

The mechanism of metastasis in the so-called "benign giant cell tumor of bone"

A case of so-called "benign giant cell tumor of bone" with an incidental histologic finding of intratumor vascular invasion is reported. The mechanism and biology of metastasis are briefly discussed. For the purposes of this presentation, the mechanism of metastasis is divided into two types--active and passive. An active type of metastasis indicates malignancy, whereas a passive type denotes a benign process. The malignant features of the conventional or typical giant cell tumor of bone are demonstrated. It is proposed that this neoplasm be labeled malignant despite its seemingly benign histologic appearance. Relative to the degree of malignancy, a lesion of this nature may be classified as either a low or a high grade type of malignant giant cell tumor.

Pulmonary leiomyosarcomas

Four cases of pulmonary leiomyosarcoma are presented. The characteristic histological features are described with specific reference to the criteria of malignancy. It is suggested that diagnosis by bronchoscopy provides insufficient material for histological grading and open lung biopsy is the diagnostic tool of choice. The available methods of treatment are discussed.

Uterine fibroleimoyomata with aortic lymph node metastases

This is a report of extensive metastases of histologically benign uterine leiomyomas to para-aortic lymph nodes in a 32-year-old woman. The pathologic features and clinical characteristics are described, and the previously recorded experience with this rare entity is reviewed.

Metastasizing leiomyoma of the uterus. S-phase fraction, estrogen receptor, and ultrastructure

A 33-year-old woman had a metastasizing leiomyoma in which mitotic figures could not be found. The tumor was composed of well differentiated smooth muscle indistinguishable from uterine leiomyoma or normal myometrium by light and electron microscopy. The S-phase fraction of the tumor, measured by in vitro tritiated thymidine labeling, was near the upper limit of the range seen in seven ordinary uterine leiomyomas and was distinctly lower than that in a uterine leiomyosarcoma. The content of estrogen receptors in the cytosol was within the range seen in uterine leiomyomas. Metastasizing leiomyoma is an actively proliferating neoplasm of mature smooth muscle that appears to be hormonally responsive. The tumor in our patient showed no clear differences from ordinary leiomyomas in findings relating to the rate of cellular proliferation, morphology, or estrogen receptor content.

Oral leiomyosarcoma. Report of a case and review of the literature pertaining to smooth-muscle tumors of the oral cavity

Primary malignant smooth-muscle tumors of the mouth have rarely been reported. A review of the literature has yielded only eleven cases; to these, a new case is added. The age, sex, and site distribution of oral leiomyosarcomas are compared with those of oral leiomyomas.

Spontaneous regression of pulmonary leiomyomas during pregnancy

Multiple pulmonary nodular densities simulating metastastic cancer were discovered in a routine chest roentgenogram of a 30-year-old pregnant woman. Lung biopsy revealed nodules composed of smooth muscle and collagenous tissue containing entrapped glandular elements. The lesions were initially interpreted as multiple pulmonary fibroleiomyomatous hamartomas (MPFLH). During pregnancy and the post-partum period, the pulmonary nodules regressed spontaneously. Critical analysis of the published cases as well as our own case indicates that multiple pulmonary fibroleiomyomatous hamartomas (MPFLH) cannot be distinguished from benign metastasizing leiomyoma (BML) by either clinical, roentgenographic, or pathologic criteria and that all represent pulmonary metastases from a primary uterine neoplasm. The spontaneous regression of the pulmonary nodules in the present case as well as the increased risk for development of progressive pulmonary insufficiency in the pre-menopausal patients indicates an apparent hormonal dependence. Total abdominal hysterectomy and bilateral salpingo-oophorectomy appears to be the treatment of choice.

Metastatic uterine leiomyomata. A case report

Pulmonary metastases from uterine leiomyomata are extremely rare and unpredictable, despite the high frequency of uterine leiomyoma. Review of the literature reveals seven previous examples of pulmonary metastasis from uterine leiomyomata; other cases may exist, but they were not considered because there was little evidence to distinguish them from leiomyosarcoma. The case we report is unusual in: 1) its prolonged course of 21 years, 2) its lack of pulmonary symptoms, despite extensive multiple nodules; and 3) the cystic change of the multiple lesions, which mimicked cystic lung disease.

[Gynecological aspects of retroperitoneal diseases (author's transl)]

Current literature was reviewed for gynecological aspects of retroperitoneal diseases. Taking into account the original histological findings retroperitoneal diseases were divided into the following groups from a gynecological point of view: 1. Malignant and benign primary retroperitoneal tumors 2. retroperitoneal organs 3. malignant and benign tumors of retroperitoneal organs 4. retroperitoneal gynecological structures 5. retroperitoneal metastases 6. other retroperitoneal diseases.

Mesenchymal tumors of the uterus. V. Intravenous leiomyomatosis. A clinical and pathologic study of 14 cases

Fourteen examples of intravenous leiomyomatosis in the FIP files were studied. Growth beyond the uterus occurred in 10 of the 14 examples, largely in vessels in the broad ligament and in uterine and iliac veins. Metastasis to the heart occurred in 1 example. The study provides evidence that is consistent with both theories of origin of intravenous leiomyomatosis; namely, that it may arise either from the wall of veins within the myometrium or be a result of unusually extensive vascular invasion from a leiomyoma of the myometrium. Intravenous leiomyomatosis should be distinguished from a leiomyoma with vascular invasion by arbitrarily limiting the designation of leiomyoma with vascular invasion to neoplasms in which the vascular growth is a microscopic finding and confined within the leiomyoma. Criteria are given for distinguishing intravenous leiomyomatosis from endometrial stromal sarcoma, leiomyosarcoma, leiomyoma with vascular invasion, and leiomyomatosis peritonealis disseminata.

Benign metastasizing uterine leiomyoma. Multiple lymph nodal metastases

A case of histologically benign lymph nodal metastases from a uterine leiomyoma in a 27-year-old woman is reported. It is postulated that fragments of a leiomyoma, detached at the time of endometrial curettage, entered dilated lymphatic channels in or adjacent to a large projecting submucous leiomyoma, and seeded several pelvic and para-aortic lymph nodes. During an interval of 8 years, these grew slowly and did not infiltrate the perinodal tissues or give rise to secondary metastases.