Potential pathogenetic link between angiomyofibroblastoma and superficial myofibroblastoma in the female lower genital tract based on a novel MTG1-CYP2E1 fusion

Vulvo-vaginal stromal tumours - Case series of a rare entity from an oncology centre in India

Vulvo-vaginal stromal tumours are a rare and diverse group of mesenchymal neoplasms unique to hormone-responsive stroma of the vulva and vagina. These tumours are mostly benign, except for the locally aggressive deep angiomyxomas. Often these tumours pose diagnostic challenges, resembling certain malignant vulvo vaginal tumours. This case series highlights clinicopathological features of four angiomyxomas; a single angiomyofibroblastoma, and another superficial myofibroblastoma, including their clinical outcomes. All patients were in their 4th or 5th decade of life. Only 1/4 angiomyxomas was correctly diagnosed at the referring hospitals. Three out of four patients harbouring angiomyxomas achieved clinical remission post-surgery, while one patient was lost to follow-up. By immunohistochemistry, tumor cells showed variable positivity for desmin, SMA, ER, and PR, and negativity for S100P and CD34. The angiomyofibroblastoma was initially misdiagnosed as a liposarcoma, and the patient was lost to follow-up after diagnosis. Immunohistochemically, the tumor cells were diffusely positive for SMA and ER; weakly and focally positive for desmin, and negative for AE1/AE3, CD34, and S100P. The patient with superficial myofibroblastoma is in clinical remission post-excision with an 18-month follow-up. Immunohistochemically, the tumor cells showed CD34 positivity. Therapeutically, none of the patient received adjuvant treatment, except for a single patient with angiomyxoma, who underwent chemoradiation for a synchronous cancer cervix post-surgery. This case series provides valuable insights into the clinical heterogeneity, diagnostic intricacies, and outcomes of vulvo-vaginal stromal tumours from an oncology centre in India, further contributing to a better understanding of these rare tumours.

Case report: Superficial cervicovaginal myofibroblastoma of the cervix with endometrial carcinoma

Introduction

A superficial cervical vaginal myofibroblastoma is a rare mesenchymal tumor, originating from the superficial stroma of the vagina and cervix. This study reports a patient, who was diagnosed with endometrioid carcinoma and a concomitant benign superficial cervicovaginal myofibroblastoma.

Case presentation

A 53-year-old female with endometrial carcinoma was admitted to the Department of Gynecology of our hospital. She had a history of breast cancer on May 23, 2010, and took toremifene citrate for 41 months. Radical resection of the endometrial carcinoma was performed at our hospital. Based on the pathological findings, she was postoperatively diagnosed with endometrial adenocarcinoma with superficial cervical vaginal myofibroblastoma. The patient continued receiving postoperative breast cancer treatment. She underwent follow-up for 23 months. No recurrence or metastasis of the endometrial cancer or superficial cervical vaginal myofibroblastoma was observed.

Conclusion

There were similarities between superficial cervical vaginal myofibroblastoma and other mesenchymal tumors of the female genital tract. Superficial cervical vaginal myofibroblastomas have a good prognosis, and the combination of tissue morphology and immunohistochemistry helped establish a definitive diagnosis.

Rare Vulvar Angiomyofibroblastoma: Case Series and Literature Review

Background

Angiomyofibroblastoma (AMFB) is an uncommon disease with few literature reports, leading to the poor understanding of its diagnosis, treatment, and postoperative follow-up plans among gynecologists.

Objective

To study the clinical and pathological features of vulvar AMFB and discuss its treatment and prognosis.

Case Summary

The 3 cases were characterized by a gradually increasing painless mass in the vulva. Preoperative diagnosis was difficult and mainly depended on ultrasonic examination. Immunohistochemistry confirmed clear boundaries of AMFB. This condition could be completely cured by surgery, and the prognosis was good.

Conclusion

The vulvar AMFB is a rare tumor that is frequently misdiagnosed before surgery. Ultrasound is preferred in auxiliary diagnosis, and surgery remains the best treatment, and long-term follow-up is necessary to avoid recurrence or other complications.

Vulvar angiomyofibroblastoma is molecularly defined by recurrent MTG1-CYP2E1 fusions

Angiomyofibroblastoma (AMF), a rare benign vulvovaginal mesenchymal tumour, poses a diagnostic challenge due to histologic and immunohistochemical overlap with other vulvar mesenchymal tumours. Recently, MTG1-CYP2E1 fusion transcripts were reported in 5/5 AMFs; no other genetic alterations have been described to date. Herein, we sought to investigate the frequency of the MTG1-CYP2E1 fusion and the presence of other potential genetic alterations in a cohort of AMFs (n = 7, patient age range: 28-49 years). Tumours demonstrated classic morphologic features including alternating hypo/hypercellular areas, capillary channels surrounded by epithelioid/spindled tumour cells, and variable amounts of mature adipose tissue. reverse transcription-polymerase chain reaction (RT-PCR) for MTG1-CYP2E1 fusion, performed in all seven cases, showed the fusion transcript in five of six cases (one case with technical failure). Two tumours, including the one lacking the fusion, were subjected to targeted next-generation sequencing (104 genes) and a sarcoma fusion assay (28 genes); the fusion negative AMF also underwent RNA sequencing. No additional mutations, copy number alterations, or fusion genes were identified with the assays employed. We conclude that the majority of AMFs harbour recurrent MTG1-CYP2E1 fusion transcripts and identification of this fusion may aid in the diagnosis.

Superficial vaginal myofibroblastoma with mushroom-like appearance: A case report with colposcopic findings and literature review

Superficial myofibroblastoma (SMF) of the lower female genital tract is a relatively rare benign mesenchymal tumor. The diagnosis is usually challenging as it shares several similar clinicopathological features with other tumors. Herein, we present a case of a 71-year-old Chinese female patient with postmenopausal vaginal bleeding. Colposcopy imaging revealed a well-circumscribed mass in the vagina with a wide pedicle, resembling a mushroom. The patient underwent surgery, and the tumor was histologically diagnosed as SMF. To the best of our knowledge, this is the first report of colposcopic imaging of a superficial vaginal myofibroblastoma. In this case study, we review the clinicopathological features of SMF of the lower female genital tract reported in the literature to improve the understanding of the disease.

Superficial myofibroblastoma of the lower female genital tract: A clinicopathological analysis of 15 cases

OBJECTIVE

To describe the clinicopathological features and differential diagnoses of 15 cases of superficial myofibroblastoma, a rare mesenchymal tumor involving the lower female genital tract.

METHODS

The clinicopathological data and immunohistochemical findings were retrospectively analyzed in 15 cases of superficial myofibroblastoma. Meanwhile, a systematic literature review was conducted.

RESULTS

The age of patients ranged from 34 to 73 years (median, 49 years). Most patients presented with nodular or polypoid masses ranging in size from 0.4 cm to 6.5 cm. Twelve tumors were located in the vagina, two in the vulva, and one in the cervix. Microscopically, the tumor was located in the subepithelial tissue, with a clear boundary and without capsule on the surface. The tumor cells were spindle, oval, stellate or wavy, and arranged in various architectural patterns of reticular, fascicular, wavy and disorderly patterns. There were no obvious cellular atypia and mitotic figures. Thin collagen fibers and thin-walled vessels could be observed in all cases. Most cases were diffusely and strongly reactive to Vimentin (12/12), Desmin (14/15), ER (15/15) and PR (13/14). Variable immunoreactivity for CD34 (8/15), Caldesmon (2/8), SMA (4/14) and CD99 (4/5) were observed. The tumors showed a low Ki67 proliferative index (≤5 %). Follow-up information was available in 10 patients and there was no evidence of recurrence or metastasis.

CONCLUSIONS

Superficial myofibroblastoma is a rare benign tumor that originates from the hormone-sensitive, subepithelial mesenchymal tissue of the lower female genital tract, and should be differentiated from other mesenchymal tumors.

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..

Case Report: Magnetic Resonance Imaging Features of Scrotal Angiomyofibroblastoma (AMF) With Pathologic Correlation

Angiomyofibroblastoma (AMF) is a rare benign myofibroblastic tumor that mainly occurs in the genital tract of middle-aged female patients. However, it can also arise in the scrotum, spermatic cord, and bladder. We described, herein, a case of a 42-year-old patient who was admitted to our hospital with a left scrotal mass. Imaging examinations showed that the mass had abundant vessels and displayed obvious progressive intensification on enhanced MRI. The following histopathological and immunohistochemical studies led to the diagnosis of AMF. Here, we describe the magnetic resonance imaging findings of a case of scrotal AMF. We hope that the information can help radiologists to identify AMF.

Practical Approach to the Diagnosis of the Vulvo-Vaginal Stromal Tumors: An Overview

Background: The category of the “stromal tumors of the lower female genital tract” encompasses a wide spectrum of lesions with variable heterogeneity, which can be nosologically classified on the basis of their morphologic and immunohistochemical profiles as deep (aggressive) angiomyxoma (DAM), cellular angiofibroma (CAF), angiomyofibroblastoma (AMFB) or myofibroblastoma (MFB). Despite the differential diagnosis between these entities being usually straightforward, their increasingly recognized unusual morphological variants, along with the overlapping morphological and immunohistochemical features among these tumours, may raise serious differential diagnostic problems. Methods and Results: The data presented in the present paper have been retrieved from the entire published literature on the PubMed website about DAM, CAF, AFMB and MFB from 1984 to 2021. The selected articles are mainly represented by small-series, and, more rarely, single-case reports with unusual clinicopathologic features. The present review focuses on the diagnostic clues of the stromal tumours of the lower female genital tract to achieve a correct classification. The main clinicopathologic features of each single entity, emphasizing their differential diagnostic clues, are discussed and summarized in tables. Representative illustrations, including the unusual morphological variants, of each single tumour are also provided. Conclusion: Awareness by pathologists of the wide morphological and immunohistochemical spectrum exhibited by these tumours is crucial to achieve correct diagnoses and to avoid confusion with reactive conditions or other benign or malignant entities.