A common tumor in an uncommon site: epithelioid Leiomyoma arising from the seminal vesicle-a case report.

BACKGROUND: Leiomyoma of the seminal vesicle is a rare leiomyoma characterized by the formation of benign leiomyomatous tissue within the seminal vesicle. Although histologically benign, excessive size can lead to urinary system disease if left untreated. Herein, we report a case of a seminal vesicle epithelioid leiomyoma. CASE PRESENTATION: A 36-year-old Chinese man sought medical attention at our hospital for urination pain and hemospermia. CT showed a 5.3 cm × 5.0 cm seminal vesicle mass with a mixed density in the right seminal vesicle. The gross specimen showed light yellow, gray, and white tissues, with softness and hemorrhage in some places. Histologically, it showed classic spindle cell proliferation, with spindle cells arranged in fascicles, and mitosis was rare. Immunohistochemistry showed frequent expression of smooth muscle markers, such as calponin, SMA, and desmin. A diagnosis of epithelioid leiomyoma was proposed according to the immunohistochemical findings and morphology. The patient did not receive adjuvant therapy. There was no evidence of tumor recurrence in the 10 months after surgery. CONCLUSIONS: We report the first case of epithelioid leiomyoma in the seminal vesicle. This disease should be included in the differential diagnostic list of seminal vesicle tumors with epithelioid morphology.

Vulvar epithelioid leiomyoma with myxoid change: A case report and literature review.

RATIONALE: Smooth muscle tumors of the vulva are infrequent neoplasms with diverse histologic features and unclear biologic behavior. Herein, we report a very rare case of vulvar epithelioid leiomyoma and review of previous reported cases of these tumors. In addition, we have discussed the representative diagnostic criteria of vulvar smooth muscle tumors and prognostic significance of epithelioid morphology. PATIENT CONCERNS: We recently met a 45-year-old woman with complaint of painful vulvar mass. INTERVENTIONS: Excisional biopsy was performed. DIAGNOSES: Pathologic examination revealed a vulvar epithelioid leiomyoma with multinodular growth pattern. Mitotic activity was rare and cellular atypia was not identified. Based on histology and immunohistochemical staining results, the case was diagnosed as vulvar epithelioid leiomyoma. OUTCOMES: After mass excision, the patient was discharged with no complication and there was no evidence recurrence for 6 months. LESSONS: After reviewing previous papers and diagnostic criterion, we thought that vulvar smooth muscle tumors with predominant epithelioid morphology may be associated with unfavorable prognosis, Therefore, pathologists should examine the epithelioid component in vulvar smooth muscle tumors carefully.

Possible involvement of inflammatory/reparative processes in the development of uterine fibroids.

Uterine leiomyomas are benign tumors in the smooth muscle layer of the uterus. The most common histological type is the "usual leiomyoma", characterized by overexpression of ECM proteins, whereas the "cellular type" has higher cellular content. Our objective is to investigate the involvement of inflammatory and reparative processes in leiomyoma pathobiology. Using a morphological approach, we investigate the presence of inflammatory cells. Next, we determine the localization of the ECM, the presence/absence of fibrotic cells via α-sma and desmin and the immunohistochemical profile of the mesenchymal cells with respect to CD34. Finally, we explore the effect of inflammatory mediators (TNF-α, IL-1ß, IL-6, IL-15, GM-CSF and IFN-γ) on pro-fibrotic factor activin A mRNA expression in vitro. Higher numbers of macrophages were found inside and close to leiomyomas as compared to the more distant myometrium. Cellular leiomyomas showed more macrophages and mast cells than the "usual type". Inside the fibroid tissue, we found cells positive for α-sma, but negative for desmin and a large amount of collagen surrounding the nodule, suggestive of myofibroblasts producing ECM. In the myometrium and leiomyomas of the "usual type", we identified numerous CD34+ fibroblasts, which are known to give rise to myofibroblasts upon loss of CD34 expression. In leiomyomas of the "cellular type", stromal fibroblasts were CD34-negative. Finally, we found that TNF-α increased activin A mRNA in myometrial and leiomyoma cells. In conclusion, this study demonstrates the presence of inflammatory cells in uterine leiomyomas, which may contribute to excessive ECM production, tissue remodeling and leiomyoma growth.

Ligation-assisted endoscopic enucleation for treatment of esophageal subepithelial lesions originating from the muscularis propria: a preliminary study.

An innovative ligation-assisted endoscopic enucleation (EE-L) technique was developed for the diagnosis and treatment of esophageal subepithelial lesions (smaller than 12 mm) originating from muscularis propria by combining endoscopic band ligation and endoscopic enucleation techniques. The aim of the study was to evaluate efficacy and safety of EE-L technique in the treatment of esophageal subepithelial lesions (smaller than 12 mm) originating from muscularis propria. Forty-seven esophageal subepithelial lesions (smaller than 12 mm) originating from the muscularis propria in 44 patients were treated with EE-L between September 2010 and September 2012. The lesion was first aspirated into the transparent cap attached to the tip of endoscope. The elastic band was then released around its base. The purpose of ligation was to force the lesion to assume a polypoid form with a pseudostalk. Endoscopic enucleation was then performed until the tumor was completely enucleated from muscularis propria using a hook knife and forceps. All tumors (median diameter: 8.2 ± 2.3 mm, range: 4-12 mm) were enucleated completely. Histopathology identified 45 tumors (95.7%) as leiomyoma, 2 (4.3%) tumors as gastrointestinal stromal tumor with very low risk. The mean time of the EE-L procedure was 12.5 ± 4.6 minutes (range: 6-23 minutes). Two patients experienced self-limiting, non-life-threatening hemorrhage after EE-L. No perforation and massive hemorrhage requiring further endoscopic or surgical intervention occurred. There were no recurrences during the 6-24 months follow-up period. EE-L offers the option of localized treatment of small esophageal muscularis propria tumors (smaller than 12 mm) with relatively few complications and low mortality, and provides the advantage of allowing a histopathological diagnosis. All the resected lesions in this study had a benign pathology.

Spontaneous leiomyomas of the gastroesophageal junction in a chimpanzee (Pan troglodytes).

A 49-y-old, female chimpanzee presented with a history of cardiac failure. Postmortem examination revealed lesions consistent with congestive heart failure and 2 incidental, round, firm, pale-tan intramural nodules (diameter, 2 cm) in the stomach at the gastroesophageal junction (GEJ). Histologically, the GEJ nodules were diagnosed as benign spindle-cell tumors. Immunohistochemical evaluation revealed neoplastic cells diffusely labeled with α-smooth muscle actin and vimentin, multifocally labeled for desmin, and were negative for c-kit (CD117). Electron microscopy revealed intracytoplasmic bundles of myofilaments with dense bodies, basal lamina, and few pinocytic vesicles in the neoplastic cells. According to these findings, leiomyomas of the GEJ were diagnosed. Gastrointestinal stromal tumors have been documented to occur in chimpanzees, but there are no reports of GEJ leiomyomas. To our knowledge, this report is the first description of spontaneous leiomyomas of the GEJ in a chimpanzee.

Unilateral ovarian agenesis and clear cell type epithelioid leiomyoma of uterus mimicking ovarian malignancy.

A case of unilateral absent ovary together with clear cell type epithelioid leiomyoma of uterus mimicking ovarian malignancy discovered during laparotomy is presented. Unilateral absence of an ovary is an extremely rare finding. Although the exact pathophysiological mechanism is not known, it could result from a defect in embryological development or asymptomatic torsion of ovary. Clear cell type epithelioid leiomyoma of uterus is also a rare variant, composed of round or polygonal 'clear' cells rather than typical spindle-shaped cells and ultra structurally differs from non-uterine counterparts.

Epithelioid cotyledonoid dissecting leiomyoma: a case report and review of the literature.

A 63-year-old mother of two, presented with blood-stained vaginal discharge and right sided lower abdominal pain. A MRI examination confirmed a right parametrial mass, abutting the lateral margin of the uterus and the patient had a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histological examination diagnosed a cotyledonoid leiomyoma, but with a new epithelioid variant. Cotyledonoid leiomyom's usually have a large, fungating appearance and demonstrate apparent widespread infiltrative growth and extension into the pelvic cavity, broad ligament and retroperitoneal space which may raise significant concern about the possibility of a malignant neoplasm. As these tumours are rare and infrequently encountered, it is imperative that clinicians be aware of this entity as they may pose a significant diagnostic and management challenge when encountered. Awareness of this newly described epithelioid cell variant of cotyledonoid dissecting leiomyoma is necessary for an accurate diagnosis and to facilitate appropriate management decisions at the time of surgery. This new variant further emphasizes the need for meticulous histopathological assessment which should be undertaken to circumvent misdiagnosis. This has direct clinical relevance to all operating gynaecologists and may have implications for litigation because patients may be inappropriately and inadvertently over-treated for an essentially benign condition.

Multiple epitheloid plexiform tumourlet leiomyoma of the uterus with focal vascular invasion.

We report the first case of multiple plexiform tumourlets showing focal vascular invasion suggesting that, unlike what the common and accepted opinion would advocate, these tumours may have a more aggressive behaviour. However, the prognosis of this variant of epithelioid leiomyoma remains unknown, due to its rarity. The main differential diagnosis of this entity are discussed, including endometrial stromal sarcoma exhibiting epitheloid cytomorphology, intravenous leiomyomatosis of epitheloid variant.

Primary meningeal sarcoma with leiomyoblastic differentiation complicating pregnancy.

Intracranial malignant tumors during pregnancy are rare. Primary meningeal sarcoma with leiomyoblastic differentiation during pregnancy has not been reported. We present the case of a 25-year-old woman in the third trimester of pregnancy with a large intracranial tumor destructing the parietal calvaria and invasion of soft tissues. Histological examination revealed primary meningeal sarcoma with leiomyoblastic differentiation. A gross macroscopical resection of the tumor with removal of the infiltrated parietal calvaria was performed after delivery of a healthy baby through caesarean section. A mass on the head rapidly enlarging during pregnancy should be considered for a malignancy of intracranial origin. Early radiological exams as well as tumor resection followed by staging and multimodality treatment should be urgently performed.

Uterine smooth muscle tumors other than the ordinary leiomyomas and leiomyosarcomas: a review of selected variants with emphasis on recent advances and unusual morphology that may cause concern for malignancy.

Uterine smooth muscle tumors are classified according to their morphologic features that include architecture, growth pattern, cellular characteristics and constituents of the intercellular stroma. While terminologies used for the pathologic diagnosis of various subtypes may be eloquent and histologically accurate, some of these are confusing for the clinician and may also be open to interpretation by different pathologists: the labeling of atypical leiomyomas epitomizes this intricate system. Clinically, it is probably more useful to classify them as either tumors with or tumors without recurrent and/or metastatic potential. The term "atypical leiomyoma" has been used to label tumors that have a low risk of recurrence and is synonymous with benign tumors. The latter are known variously as leiomyoma with bizarre nuclei, symplastic leiomyoma, or pleomorphic leiomyoma. Variants of benign uterine smooth muscle tumors, such as mitotically active leiomyoma, cellular and highly cellular leiomyoma, epithelioid leiomyoma, and myxoid leiomyoma each have distinctive hallmarks that enable subclassification. Nevertheless, they may occasionally possess one or more unusual features that are cause for alarm. Tumors that have a dissecting growth pattern, with or without extrauterine extension, may mimic malignancy both grossly and microscopically. The current review discusses the pathologic diagnosis of and terminology applied to selected variants of uterine smooth muscle tumors other than the ordinary leiomyomas and leiomyosarcomas with emphasis on unusual reported features that may indicate malignancy. This includes an update on uterine smooth muscle tumor of uncertain malignant potential (STUMP), intravenous leiomyomatosis, benign metastasizing leiomyoma, and diffuse leiomyomatosis. Their clinicopathologic features, differential diagnoses, and management options based on findings in the previously reported cases will also be reviewed.

Epithelioid smooth muscle tumors of the uterus do not express CD1a: a potential immunohistochemical adjunct in their distinction from uterine perivascular epithelioid cell tumors.

Uterine epithelioid smooth muscle tumors and uterine perivascular epithelioid cell tumors (PEComas) are known to display such a substantial overlap in morphologic and immunophenotypic characteristics that the existence of the latter as a distinct clinicopathologic entity at this location has been called into question. Recent research suggests that the constituent entities of the PEComa family at all anatomical locations, including lymphangioleiomyomatosis of the uterus, uniformly display immunoreactivity for CD1a. The purpose of this study is to determine the proportion of uterine epithelioid smooth muscle tumors that may similarly be CD1a-positive. Representative sections from 18 archived epithelioid smooth muscle tumors of the uterine corpus (6 epithelioid leiomyosarcomas and 12 epithelioid leiomyomas), diagnosed and classified as such based on World Health Organization criteria, were subjected to immunohistochemical stains for CD1a and HMB-45. The epithelioid component of the tissue sections evaluated ranged from 10% to 100% (mean, 70%). Two cases were composed predominantly of cells with overtly clear cytoplasm. All cases were entirely negative for CD1a. Of 18 cases, 1 (5.5%) (an epithelioid leiomyosarcoma) displayed immunoreactivity for HMB-45 in scattered lesional cells that constituted approximately 5% of the overall tumoral volume for the case. All others were HMB-45-negative. Given their rarity, future studies are required to confirm that all PEComas of the uterus are indeed uniformly positive for CD1a. However, if the latter staining pattern is confirmed, our findings herein suggest that CD1a may be a useful immunohistochemical adjunct in distinguishing uterine epithelioid smooth muscle tumors from uterine PEComas.

Molecular and cytogenetic characterization of plexiform leiomyomata provide further evidence for genetic heterogeneity underlying uterine fibroids.

The plexiform variant of uterine leiomyomata (UL) is named for its ribbons or nests of smooth muscle cells that have a rounded, epithelioid shape caused by their entrapment in abundant extracellular matrix. Plexiform UL are currently classified as epithelioid smooth muscle tumors alongside the less predictable, "true" epithelioid tumors (ie, leiomyoblastomas). Karyotypes of six plexiform UL cases were studied, and their abnormalities were found to differ from those of leiomyoblastomas. Analyses using real-time polymerase chain reaction, immunohistochemistry, and fluorescence in situ hybridization demonstrated elevated mRNA and protein levels of the architectural factor HMGA2 and, in some cases, increased DNA copy number. Four of these plexiform UL were profiled with Affymetrix human U133 plus 2.0 expression arrays. Cluster analysis using genes previously shown to discriminate benign and malignant uterine smooth muscle tissues revealed that the plexiform tumors form an isolated group in the benign branch. This is in contrast to an earlier finding in which another variant, cellular UL characterized by loss of a portion of the short arm of chromosome 1, clustered with malignant leiomyosarcomas. These results provide additional evidence of genetic heterogeneity underlying UL of various histological types. We further suggest that plexiform UL should be classified among tumors with extensive hyalinization rather than with "true" epithelioid smooth muscle neoplasms.