Myoepithelioma-like tumour of the vulvar region

Myoepithelioma-Like Tumor of the Vulvar Region: A Clinicopathologic Study of Four Cases

Myoepithelioma-like tumors of the vulvar region (MELTVR) are solid tumors found in the vulva of adult women. They have a similar histopathology to myoepithelioma but differ in immunohistochemical phenotype and genetic changes. In this study, we report four examples of MELTVR, occurred in the external genitalia and mons pubis of adult women aged 32 to 39 years. The tumors presented as subcutaneous masses without obvious tenderness. The tumors were composed of a mixture of myxoid and nonmyxoid components, and myxoid areas accounted for 5% to 80% of the tumor volume. The tumor cells were spindle-shaped or epithelioid, with abundant cytoplasm, vesicular nuclei, and small nucleoli. The nuclear atypia was mild to moderate, with 0 to 10 mitotic figures per 10 high-power fields. Immunohistochemically, all four tumors showed consistent positivity for EMA, calponin and ER; three tumors exhibited PR expression. All tumors were negative for S100 protein and SMA. AE1/AE3 expression was absent in all except one tumor, which showed rare positivity. SMARCB1/INI1 expression was deficient in all tumors. EWSR1 and FUS rearrangements were absent. All tumors were treated through surgery. All patients were alive without recurrence on most recent follow-up. Together, this overview of four additional tumors of MELTVR offers further insight into this rare and poorly understood disease.

Update on Mesenchymal Lesions of the Lower Female Genital Tract

This article provides an update of the recent developments in mesenchymal tumors of lower genital tract. We focus on the characterization of recurrent molecular events in certain genital stromal tumors, for instance angiomyofibroblastomas and superficial myofibroblastomas. Moreover, fusions involving Tyrosine-kinases receptors (NTRK, FRFR1, RET, COL1A1-PDGFB) have been demonstrated in an emerging group of mesenchymal tumors characterized by a fibrosarcoma-like morphology and a predilection for uterine cervix of premenopausal women. We also cover the topic of smooth muscle tumors of the lower genital tract, which can be now classified using the same diagnostic criteria than their uterine counterpart..

Myoepithelioma-like tumors of the vulvar region: A case report and review of the literature

Myoepithelioma-like tumors of the vulvar region (MELTVR) is a kind of solid tumor newly recognized in recent years, which is characterized by mesenchymal tumors of adult female vulva. The histopathology is similar to myoepithelioma, but the immunohistochemical phenotype and genetic changes are different from myoepithelioma. It usually has clear boundary and partial capsule, mixed with two forms of cells (epithelioid and spindle), the cells are mild, the nucleoli are clear, mitoses are rare, some cases have myxoid differentiation. In this article, a case of MELTVR diagnosed in our hospital is discussed. The patient was a 43-year-old female who finds a neoplasm in the pubic tubercle 4 months ago. Local resection was performed. Pathological examination showed that the boundary of the tumor was clear with partial capsule. The cells were arranged in cords or nests, and partially infiltrated the surrounding adipocytes. The tumor cells had two morphologies, epithelioid or spindle shaped. The spindle type cells were dominant, with bright cytoplasm, obvious nucleoli, rare nuclear mitosis (about 1/10HPF), and no necrosis was observed. Immunohistochemically, the tumor cells were positive for vimentin, epithelial membrane antigen, estrogen receptor, progestogen receptor, calponin and were partially positive for cathepsin k. INI1/SMARCB1 expression was deficient. There was no recurrence or metastasis during the 8-month-long follow-up. The unique feature of this case was that the site of the disease was not the vulva, but in front of the pubic tubercle, there was no large amount of mucus production, and the cytoplasm of most tumor cells was transparent. Due to our limited knowledge of MELTVR, its pathogenesis and tissue origin are not clear. Clinicians should be aware of such potential patients.

Myoepithelioma-like tumour of the vulval region: A case report

Myoepithelioma-like tumours of the vulvar region (MELTVR) are a newly described group of spindle cell neoplasm. Morphologically, they consist of epithelioid to spindled cells in a myxoid to collagenous stroma and can resemble epithelioid sarcomas, myoepithelial carcinomas or extraskeletal myxoid chondrosarcomas. However, they have a distinct pattern of immunohistochemical staining characterised by positivity for EMA, ER, PR and negativity for cytokeratin, GFAP and S100. Nuclear staining for INI-1 is lost. In addition, they lack the characteristic gene arrangements of these other lesions. MELTVR can recur locally when incompletely excised, however, do not appear to metastasize. We report a case of a MELTVR in a 49-year-old woman arising in the right mons pubis.

Update on SWI/SNF-related gynecologic mesenchymal neoplasms: SMARCA4-deficient uterine sarcoma and SMARCB1-deficient vulvar neoplasms

Our knowledge regarding the role of genes encoding the chromatin remodeling switch/sucrose non-fermenting (SWI/SNF) complex in the initiation and progression of gynecologic malignancies continues to evolve. This review focuses on gynecologic tumors in which the sole or primary genetic alteration is in SMARCA4 or SMARCB1, two members of the SWI/SNF chromatin remodeling complex. In this review, we present a brief overview of the classical example of such tumors, ovarian small cell carcinoma of hypercalcemic type, and then a detailed review and update of SMARCB1-deficient and SMARCA4-deficient tumors of the uterus and vulva.