Superficial myofibroblastoma of the lower female genital tract: report of a series including tumours with a vulval location

Vulval superficial myofibroblastoma with lymphocytic and eosinophilic infiltrate

We present the case of a vulval superficial myofibroblastoma with a lymphocytic and eosinophilic rim in a woman in her late 20s. The tumour presented in pregnancy as a cystic lesion with pain and increasing size. While the histopathology of superficial myofibroblastomas has been well defined in the literature, to our knowledge, there has been no documentation of the presence of an inflammatory infiltrate of lymphocytes and eosinophils surrounding and within the tumour. This may potentially act as a diagnostic or prognostic reference.

A giant superficial myofibroblastoma involving the vagina and pelvis: A case report and review of the literature

Superficial myofibroblastoma is a rare benign mesenchymal tumor that presents a challenge in accurate preoperative diagnosis because of its overlapping radiological and histological features. A 27-year-old woman presented with a history of increasing abdominal girth over the prior year and pelvic mass for 1 month. Imaging confirmed the presence of a giant well-circumscribed cystic-solid tumor involving both the extraperitoneal pelvis and vagina. After exploration and excision, superficial vaginal myofibroblastoma was diagnosed pathologically. The patient underwent surgical excision and had no postoperative complications at the 1-month follow-up. Imaging features and clinical reasoning can aid in differentiating superficial myofibroblastoma from more aggressive entities or malignant tumors and guide suitable and appropriate surgical approaches.

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.

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..

Nonsquamous Lesions of the Vulvar Skin and Subcutaneous Tissue: A Review (Part 2)

OBJECTIVE

The aim of this second article was to complete part 1 review of nonsquamous lesions of the vulvar skin and subcutaneous tissue (Journal of Lower Genital Tract Disease, 2021), clinically and pathologically, based on the fifth edition of the World Health Organization tumor classification.

MATERIALS AND METHODS

A database search of PubMed and Google Scholar was performed between 1970 and 2021, using the search terms "vulva," "lower genital tract," and "non-squamous lesions." The search was limited to "human gynecological pathology." Full article texts were reviewed, and reference lists were screened for additional articles. We excluded abstracts and articles written in the non-English language.

RESULTS

An initial list of 400 articles was identified. Thirty-seven articles discussed clinicopathological features of nonsquamous lesions of the vulvar skin and subcutaneous tissue.

CONCLUSIONS

Clinicopathological features of nonsquamous lesions of the vulvar skin and subcutaneous tissue as categorized by the updated World Health Organization classification are presented.

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.

The ultrasonographic characteristics of female periurethral solid masses

INTRODUCTION AND HYPOTHESIS

Studies on the imaging of female periurethral masses are sparse, and most are focused on cystic lesions. In this article, we studied female periurethral solid masses and reported their ultrasonographic features.

METHODS

Fifteen women with periurethral solid masses pathologically diagnosed between January 2008 and April 2021 were assessed.

RESULTS

Each patient had only one mass. The pathological types included urethral caruncle (5 patients), urethral leiomyoma (3 patients), urethral malignant tumor (MT) (3 patients), periurethral spindle tumor (3 patients) and cartilage necrosis of pubic symphysis (PS) (1 patient). On ultrasound, all urethral caruncles were located at the urethral meatus. They were hypoechoic/isoechoic and rich in blood flow signal. Each leiomyoma presented as a well-defined hypoechoic mass with an oval shape. The urethral MT had inhomogeneous/isoechoic echoes, with medium to abundant blood flow signal. The spindle cell tumors had regular/irregular shapes, moderate/high density echogenicity and little/rich blood flow signals. The articular cartilage necrosis of PS was regular in shape, with mixed echogenicity and no blood flow.

CONCLUSIONS

Ultrasound imaging is a convenient and useful method to evaluate the morphological characteristics of female periurethral solid masses.

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

Angiomyofibroblastoma and superficial myofibroblastoma are distinctive benign mesenchymal tumors occurring in the female lower genital tract. Despite their significant overlapping clinicopathologic features, including the presence of bland-looking spindle or oval cells with myofibroblastic or myoid differentiation, the tumors have been regarded as separate entities. Although subepithelial, hormone-sensitive mesenchymal cells of the female lower genital tract are considered as their potential common progenitor cells, their potential kinship or pathogenetic similarities remain elusive. Based on the identification of a novel RNA sequencing-based MTG1-CYP2E1 fusion transcript in an angiomyofibroblastoma index case, we investigated an additional ten samples of the tumor and its site-specific histological mimics, including eight superficial myofibroblastomas, four deep angiomyxomas, four cellular angiofibromas, three fibroepithelial stromal polyps, and eight non-site-specific mesenchymal tumors occurring in the female lower genital tract. Using reverse transcription-polymerase chain reaction, we showed that the MTG1-CYP2E1 fusion transcripts were consistently detectable in angiomyofibroblastomas (5/5, 100%) and often in superficial myofibroblastomas (3/5, 60%) but were not detected in the other examined site-specific or non-site-specific mesenchymal tumors. Our immunohistochemical experiments showed that CYP2E1, an isoenzyme belonging to the cytochrome P450 superfamily, exhibited increased positivity in tumors with MTG1-CYP2E1 than was observed in fusion-negative tumors (RR = 6.56, p = 0.001). The results of our study provide further evidence supporting the assertion that angiomyofibroblastoma and superficial myofibroblastoma represent phenotypic variants of site-specific mesenchymal tumors and share a common oncogenic mechanism.

Cellular angiofibroma arising in the anorectal region: clinicopathologic and immunohistochemical analysis of five cases

Cellular angiofibroma (CA) is a rare, benign mesenchymal tumor with a predilection to the distal female and male genital tract. Extragenital examples of CA, including anorectal CAs, are exceedingly rare and documented mainly as single case reports. Herein, we analyze the clinicopathological and immunohistochemical features of 5 anorectal CAs. There were 4 males and one female ranging in age from 45 to 70 (median, 58) years at the time of surgery. Tumors arose in the superficial tissues of the anorectal (n = 3) and perianal (n = 2) regions. The tumors were well circumscribed ranging from 2 to 6.7 (median, 5.4) cm. All demonstrated a low to moderately cellular proliferation of cytologically bland spindled cells within a variably dense collagenous and focally myxocollagenous stroma and small- to medium-sized vessels featuring perivascular collagen deposition. Two cases showed degenerative and/or inflammatory changes. All 5 tumors strongly expressed CD34 and androgen receptor proteins, more variably expressed estrogen (n = 5) and progesterone (n = 4) receptor proteins and desmin (n = 3), and focally expressed alpha-smooth muscle actin (n = 3), GATA-3 (n = 2), and p16 (n = 1). Retinoblastoma protein expression was reduced (n = 4) (compared with expression in endothelial cells) or completely lost (n = 1). All patients were treated with simple surgical excision, and the 2 study members with follow-up data showed no evidence of local recurrence over a postoperative follow-up interval of 23 and 73 months. In comparison with conventional genital tract CA, our 5 anorectal CAs occurred mostly in males, were generally less cellular, and appear to follow a similar uneventful clinical course.

Superficial myofibroblastoma of the vagina with a stalk: case report of a rare vaginal tumor with notable radiological findings

Superficial myofibroblastoma is a rare benign mesenchymal tumor which predominantly occurs in the female lower genital tract. Here we present a case of a 42-year-old female patient with prolonged vaginal bleeding. Radiological imaging revealed a well circumscribed mass in the vagina with a stalk. The patient underwent surgery and the tumor was histologically diagnosed as superficial myofibroblastoma. Notably, this is the first report of the radiological imaging of a superficial myofibroblastoma harboring a stalk arising from the vaginal wall. We compared the radiological images with histological findings and discuss major differential diagnosis of vaginal tumors. Despite the challenging nature of preoperative diagnosis of mesenchymal vaginal tumors, radiological features may aid in differentiating them from other more aggressive entities or malignant tumors.

HMGA2 Is a Useful Marker of Vulvovaginal Aggressive Angiomyxoma But May Be Positive in Other Mesenchymal Lesions at This Site

Aggressive angiomyxoma (AA) is a rare mesenchymal neoplasm occurring almost exclusively in the vulvovaginal region and which has a wide differential diagnosis. It has previously been suggested that the nuclear transcription factor HMGA2 is a useful marker of AA, although the number of studies is limited. We investigated HMGA2 immunoreactivity in a large series (n=284) of vulvovaginal mesenchymal lesions. HMGA2 nuclear staining was classified as diffuse (≥50%), focal (<50%), or negative. Of 38 cases of AA, 26 (68%) were positive; 77% (n=20) of these exhibited diffuse staining. Of the 41 smooth muscle tumors, 18 (44%) were positive with 16 (89%) exhibiting diffuse staining. 80 fibroepithelial stromal polyps were included and 15 (19%) were positive (8 diffuse; 7 focal). Most of the fibroepithelial stromal polyps that exhibited diffuse HMGA2 immunoreactivity were large and edematous. Occasional cases of a variety of other lesions were positive, including 1 of 30 superficial myofibroblastomas and 1 of 16 angiomyofibroblastomas. Cellular angiofibromas (n=12) and superficial angiomyxomas (n=6) were always negative. Our results confirm that HMGA2 is a useful marker of AA but a significant minority of cases are negative. The marker also lacks specificity, since a high percentage of smooth muscle tumors are positive, although these typically do not bear a close morphologic resemblance to AA. A novel observation in our study is positive staining of some fibroepithelial stromal polyps, particularly when large and edematous; these are particularly likely to be confused morphologically with AA and positive staining with HMGA2 represents a significant diagnostic pitfall.

Mesenchymal lesions of the vulva

Mesenchymal lesions of the vulva include site-specific entities limited to the lower genital tract, as well as a range of non-site-specific tumors that are more common at extragenital sites. Site-specific lesions include fibroepithelial stromal polyp, cellular angiofibroma, angiomyofibroblastoma, and aggressive angiomyxoma. Non-site-specific tumors that may occur in the vulva include those of smooth muscle, skeletal muscle, vascular, neural, adipocytic, and uncertain differentiation. This review discusses both site-specific and non-site-specific vulvar mesenchymal lesions including non-neoplastic proliferations, benign neoplasms, locally aggressive neoplasms with a predilection for local recurrence, neoplasms of indeterminate biologic potential, and frankly malignant neoplasms with a high risk of distant metastasis and death. Accurate diagnosis is essential for proper management, and is facilitated by correlation with clinical findings and targeted application of immunohistochemical and molecular studies.

A rare case of vulvar superficial myofibroblastoma associated with ambigous and unusual differential diagnosis

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Superficial myofibroblastoma of the Labia Majora.

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Differential diagnosis between vulvar superficial myofibroblastoma and cyst/hydrocele of Nuck duct.

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Differential diagnosis between vulvar superficial myofibroblastoma and inguinal/crural hernia.

Potential Diagnostic Pitfalls in Evaluating Immunohistochemistry for Cervical Myofibroblastomas

Cervicovaginal myofibroblastoma (CVM) is a rare benign mesenchymal tumor of the lower female genital tract that shows chromosomal loss of 13q14 (RB1 gene located in this region). The aim of this study was to investigate the utility of immunohistochemistry (IHC) for desmin, CD34, and Rb in diagnosing CVM. All cervical polyps diagnosed from July 2016 to July 2017 were retrospectively reviewed. Cases showing morphologic myofibroblastic differentiation were evaluated by IHC for desmin, CD34, and Rb. Desmin and CD34 staining was recorded as positive or negative. Rb nuclear staining was graded as follows: 0 (<10%), 1 (10%-25%), 2 (>25%-50%), 3 (>50%-75%), or 4 (>75%). Intact nuclear expression of Rb in endothelial cells served as an internal positive control. IHC was performed on 76 cases with 14 excluded from the final cohort due to poor Rb internal control. A total of 61/62 (98.4%) cases were positive for desmin and CD34 with the following Rb distribution: grade 0 (n=53, 86.9%), grade 1 (n=5, 8.2%), grade 2 (n=2, 3.3%), and grade 3 (n=1, 1.6%). One case negative for desmin and CD34 showed grade 3 Rb staining. Upon rereview of the histology, 7/175 cases (4%) were morphologically and immunohistochemically compatible with CVM (desmin and CD34+ grade 0 Rb staining). CVM is a rare and under-recognized entity (4% of cervical polyps) for which morphology remains the mainstay of diagnosis. IHC reliance serves as a potential diagnostic pitfall as 86.9% of cases showing myofibroblastic differentiation demonstrated the staining pattern of desmin and CD34 positivity and Rb deficiency.

Superficial myofibroblastoma of the genital tract: a case report of the imaging findings

Superficial angiomyofibroblastomas are mesenchymal tumours that occur in the genital tract and are well described pathologically. This case report reviews the imaging appearances and highlights the MRI findings, which have not been previously described. We describe the occurrence of this lesion in a vaginal cyst, which to the authors’ knowledge, has also not been previously described. The histological findings are also presented here.

Superficial Myofibroblastoma in the Vulva Mimicking Aggressive Angiomyxoma: A Case Report and Review of the Literature

Background: Superficial myofibroblastoma (SMF) is a very rare benign mesenchymal tumor in the female lower genital tract. Only 46 cases have been reported in the English language literature, among which only 7 cases arose in the vulva. Sometimes SMF histologically mimics aggressive angiomyxoma (AA) in which massive myxoid change in stroma is characteristic. We herein report a case of vulvar SMF with prominent myxoid stroma and review the literature with the emphasis on the differential diagnosis of SMF and AA. Case presentation: a 37-year-old woman presented with a painless mass in the vulva. Magnetic resonance imaging (MRI) showed a well-circumscribed 7 cm mass in the subcutis of the vulva. The tumor was resected. Histopathologically, the tumor was characterized by sparsely populated spindle-shaped cells in the fibromyxoid stroma. Thin-walled blood vessels were detected. Mitoses or pleomorphism was not found. Tumor cells were positive for vimentin, ER, PgR, and desmin. Some cells were positive for alpha-SMA and CD34. All cells were negative for S100 protein. Conclusions: because SMF and AA show different clinical prognoses, distinguishing SMF from AA is important. However, SMF may share many common histological features with AA: superficial localization (above fascia), sharp borderline from adjacent tissue, expansive growth pattern; a specific vascular pattern will lead to an accurate diagnosis of SMF. Familiarization with the histological characteristics of the two entities will help to make a prognostic prediction.

Cervical superficial myofibroblastoma: Case report and review of the literature

Superficial myofibroblastoma of the lower female genital tract is a rare benign, recently recognized neoplasm that mostly affects the vulvovaginal area. Our report discusses a case of cervical superficial myofibroblastoma of the lower female genital tract in a 45-year-old patient who is presented with menometrorrhagia. On examination, she had multiple uterine fibroids and a circumscribed submucosal mass lesion involving the anterior lip of cervix. At hysterectomy, histopathological examination of the cervical mass revealed a relatively hypocellular tumor consisted of bland spindled and stellate cells. An immunohistochemistry evaluation revealed reactivity for CD34, desmin, and smooth muscle actin. This neoplasm should be included in the differential diagnosis of cervical mass lesions. This tumor also needs to be differentiated from other mesenchymal lesions of lower female genital tract.

Clinicopathologic evaluation of myofibroblastoma: A study in two hospitals

OBJECTIVE

To report various anatomic locations and clinical characteristics of pathologically proven myofibroblastoma in Koran patients.

METHODS

Pathologic reports of patients who underwent surgeries at two centers between April 2003 and March 2016 were retrieved from the electronic medical record system of the hospital. Pathologic reports were included after performing a search using the keyword "myofibroblastoma".

RESULTS

The cohort consisted of 11 subjects and included eight female and three male individuals. The patients' ages ranged from 9 to 66 years. Tumors were located in the vagina in three patients and presented in the breast in seven patients. One case presented with an abdominal mass. The tumors ranged in mean size from 4.0 to 53.0 mm. Despite a relatively long-term follow-up, no case had evidence of tumor recurrence.

CONCLUSION

We evaluated the various anatomic locations of pathologically proven myofibroblastoma in Korean patients. As an extremely rare tumor, physicians should pay special attention to differential diagnosis. Surgical resection is the preferred method for a cure, and the recurrence rate is extremely low.

Superficial myofibroblastoma of the lower female genital tract with description of the MRI features

Superficial myofibroblastomas of the lower female genital tract are an unusual type of benign mesenchymal tumour. To the authors’ knowledge, there has been no previous imaging description of a superficial myofibroblastoma in the literature. Here, we describe a case that presented with symptoms consistent with vaginal prolapse. However, a mass was palpable on clinical examination with unusual features on MRI. Following surgery, the histopathological features were considered consistent with superficial myofibroblastoma. By presenting the MRI and histological findings, we aim to raise awareness about this lesion so that it may be considered in the differential diagnosis of a vaginal mass.

Genital soft tissue tumors

Mesenchymal neoplasms of the vulvovaginal and inguinoscrotal regions are among the most diagnostically challenging specimens in the pathology laboratory owing largely to their unique intersection between general soft tissue tumors and relatively genital-specific mesenchymal tumors. Genital stromal tumors are a unique subset of soft tissue tumors encountered at this location, and this group includes fibroepithelial stromal polyp, superficial (cervicovaginal) myofibroblastoma, cellular angiofibroma, mammary-type myofibroblastoma, angiomyofibroblastoma and aggressive angiomyxoma. Aside from the striking morphologic and immunophenotypic similarity that is seen with these entities, there is evidence that a subset of genital stromal tumors may be linked genetically. This review will focus on simplifying this group of tumors and provide the pathologist or dermatopathologist with practical management information. Smooth muscle tumors of the external genitalia will also be discussed.

Myofibroblastoma: report of a rare entity in the pediatric population

Fibroblastic and myofibroblastic tumors constitute an important group of neoplasms in children and adolescents. These span the full spectrum of clinical behavior, ranging from benign to intermediate and malignant. We report a case of a benign mesenchymal tumor with myofibroblastic differentiation in a 9-year-old girl arising in the left groin that met the histologic features described for myofibroblastoma in adults. Two types are recognized in adults: angiomyofibroblastoma and mammary-type myofibroblastoma of soft tissue. Our case shared features of both these subtypes but was not typical of either one, and we therefore designated our case simply as "myofibroblastoma." Our case showed expression of estrogen receptor protein, which is characteristic of adult lesions, but not a deletion of 13q14, as has been reported in some adult cases. In the English-language literature, only 6 cases have been reported in patients under 21 years of age, and all but 1 were teenagers. Pediatric surgeons, oncologists, and pathologists should be aware that such a benign entity can occur in this patient population and could be confused with other lesions, including malignant ones.

Vaginal superficial myofibroblastoma: a rare mesenchymal tumor of the lower female genital tract and a study of its association with viral infection

Superficial myofibroblastoma is a rare mesenchymal tumor in the lower female genital tract. The exact etiology of superficial myofibroblastoma remains unclear. The association of viral infection and mesenchymal tumors has been well established in some particular types of soft tissue tumors. In the lower female genital tract, the intimate correlation of viral infection and tumor pathogenesis has been also proposed. We present a 59-year-old woman with postcoital bleeding for 1 month. The pelvic examination revealed a 2-cm polypoid mass mimicking leiomyoma at the vaginal fornix. Local excision was performed, and the pathological examination revealed a superficial myofibroblastoma. No tumor recurrence was noted during the 12-month follow-up. Pathological differential diagnosis of this tumor from other mesenchymal tumors is essential because of its distinct clinicopathological features. Furthermore, fluorescence in situ hybridization of human papilloma virus (HPV) and Epstein-Barr virus (EBV), as well as immunohistochemical staining of human herpesvirus 8 (HHV8), was negative in tumor cells. To the best of our knowledge, we are the first group to study the possible relationship of viral infection and the occurrence of this mesenchymal tumor. Our results suggested no association of vaginal superficial myofibroblastoma and infection with HPV, EBV, or HHV8.

The 2 stromal compartments of the normal cervix with distinct immunophenotypic and histomorphologic features

Cervical plasticity is partially attributed to subepithelial stromal cells. Knowing this population of cells in its variable physiologic states, with its immunophenotypic variations, will lead to better understanding of neoplastic processes related to these stromal cells. We reviewed slides of cervices from premenopausal, postmenopausal, and postpartum patients and used mesenchymal immunohistochemical stains. Results demonstrate 2 distinct subepithelial compartments, within the ectocervix and the endocervix/transformation zone. The endocervix/transformation zone has twice the number of stromal cells as the ectocervix, regardless of age. Ectocervical stromal cells are desmin+/smooth muscle actin (SMA)-, and endocervical stromal cells are desmin+/SMA-. In postpartum/premenopausal patients, the cervix has less desmin+ ectocervical and SMA- endocervical cells. In postmenopausal/prolapse patients, the cervix has no desmin+ ectocervical cells. Desmin+/SMA, calponin, caldesmon, myogenin, myoD1, CD34- cells could represent unusual myofibroblasts that should not be confused with a neoplastic process, especially if a mass is not present.

Solitary Fibrous Tumor of the Vagina

Solitary fibrous tumor, initially described in the pleura, is now known to occur in various extrathoracic sites. However, its occurrence in the female genital tract, especially the vagina, is extremely rare. The authors report here a case of a well-circumscribed vaginal spindle cell nodule in a 48-year-old woman with features consistent with solitary fibrous tumor. The diagnosis was established histologically by the varying pattern with hypocellular fibrous areas alternating with hypercellular areas and hemangiopericytoma-like areas and, immunohistochemically by the strong positive reaction for CD34 and Bcl2 with a negative reaction for all other spindle cell and epithelial markers. The differential diagnosis is discussed and a review of the literature is presented.

Cellular angiofibroma: analysis of 25 cases emphasizing its relationship to spindle cell lipoma and mammary-type myofibroblastoma

Cellular angiofibroma represents a rare benign mesenchymal tumor, occurring mainly in the superficial soft tissue of the genital region. The involvement of 13q14 in some cases confirmed the morphological suggested link with spindle cell lipoma and mammary-type myofibroblastoma. We analyzed the clinicopathological and immunohistochemical features of 25 cases, and performed in a number of cases additional molecular studies. There were 17 female and 8 male patients (age ranged from 27 to 83 years); females tended to be younger. A marked predilection for the vulva (n=13) was observed, and neoplasms in males were predominantly located in the inguinal region (n=4), and one case each in the scrotum, perianal, the knee, and the upper eyelid. The tumors arose most commonly in the superficial soft tissue and were well circumscribed in all but two cases. The tumor size ranged from 1 to 9 cm. All lesions were composed of spindle-shaped cells associated with numerous small- to medium-sized blood vessels; however, a broad morphological variation with foci of lipogenic differentiation in nine cases and sarcomatous transformation in one case was found. By immunohistochemistry, 11 out of 22 cases expressed CD34. A focal reaction for α-smooth muscle actin was observed in 9 out of 22 cases, and two cases each stained weak and focally positive for epithelial membrane antigen and CD99. In all seven cases tested, a monoallelic deletion of RB1 was detected by FISH analysis. Follow-up, available in 14 patients, showed neither local recurrence nor metastasis. In conclusion, we affirm the link between cellular angiofibroma, spindle cell lipoma, and mammary-type myofibroblastoma, showing a spectrum of one entity with morphological variations dependent on anatomic location.

Immunohistochemical Markers of Value in the Diagnosis of Mesenchymal Lesions of the Female Genital Tract

Pure mesenchymal tumors may occur anywhere in the female genital tract, but they are most common in the uterine corpus, leiomyoma being by far the most prevalent. These tumors, and other uncommon mesenchymal lesions within the uterine corpus and elsewhere in the female genital tract, may result in several diagnostic problems. Morphology remains paramount and, in most cases, an unequivocal diagnosis can be made based on examination of the hematoxylin and eosin stained sections, combined with an appreciation of the clinical and gross pathologic features. In difficult cases, immunohistochemistry can significantly contribute to the final diagnosis. In this article, the immunohistochemistry of neoplastic and nonneoplastic mesenchymal lesions of the female genital tract is discussed site by site, concentrating on markers that are of value in diagnosis and in differential diagnosis. The immunophenotype of mixed epithelial and mesenchymal neoplasms and pure epithelial neoplasms with a component of spindle cells is discussed, where appropriate, because these can enter into the differential diagnosis of a pure mesenchymal lesion.

Application of immunohistochemistry to gynecologic pathology

CONTEXT

A large variety of tumors and lesions arise in the female genital tract. Although the majority of these can be correctly recognized on routine hematoxylin-eosin-stained slides, occasional cases present a diagnostic challenge. Immunohistochemical stains are extremely useful in resolving many of these problematic cases. As the knowledge in this area is constantly expanding, it is useful to have this updated information in a review form for easy access.

OBJECTIVE

To present our current knowledge of immunohistochemistry of the lesions of the female genital tract in a readily accessible form.

DATA SOURCES

The review is based on previously published articles on this topic.

CONCLUSIONS

Immunohistochemical stains help in reaching a conclusive diagnosis in a variety of problematic lesions seen in gynecologic pathology. As in any other system, immunohistochemical findings need to be interpreted in light of the clinical history and morphologic findings.

Tubulo-squamous Polyp

We report 10 cases of a morphologically distinct vaginal polyp which has hitherto not been characterized. The polyps occurred in women aged 39 to 78 years (most were postmenopausal) and were from 1.0 to 3.0 cm. Most of whose location is known to us were in the upper vagina. Histologically, all the polyps were remarkably similar and composed of well-circumscribed expansile nests of epithelial cells embedded in a hypocellular fibrous stroma. The epithelial elements, which were morphologically bland, were predominantly glycogenated or nonglycogenated squamous in type but small tubules were present at the periphery of some of the nests in all cases. Some of the squamous nests exhibited central necrosis with or without calcification and, in 3 cases, some contained keratin pearls. In 3 cases, a few tubules unassociated with squamous elements were present. In 3 of 4 cases tested, the cells lining the tubules were positive with prostatic acid phosphatase and in 2 of 4 with prostate-specific antigen. The epithelial elements reacted with broad-spectrum cytokeratins and cytokeratin 7 but the mesenchymal component was negative. The squamous elements were estrogen receptor positive and the mesenchymal component estrogen and progesterone receptor positive. The histologic features of this polyp, which we term "tubulo-squamous polyp of the vagina," are constant and distinctive and differ from other polyps and from mixed tumor of the vagina. Several cases reported in the literature as vaginal mixed tumor or Brenner tumor are likely examples of this entity. Possible theories of histogenesis include a Mullerian origin, derivation from mesonephric remnants or derivation from urogenital sinus-derived epithelium. Positive staining in some cases with prostatic acid phosphatase and prostate-specific antigen raises the possibility of ectopic prostatic tissue, although the overall appearance is different from that entity, or derivation from paraurethral Skene glands, the female equivalent of prostatic glands in the male.

Solitary Fibrous Tumor of the Female Genital Tract A Case Report and Review of the Literature

Originally thought to be limited to mesothelial-lined surfaces, solitary fibrous tumor (SFT) has now been reported in numerous extrathoracic sites. The female genital tract is among the rarest reported sites involving SFT, and only a handful of cases have been described. Although features pointing to a more malignant biological behavior have been described, these tumors remain unpredictable in their clinical course. We present a case of primary SFT originating in the vulva of a 45-year-old woman, only the fourth such case and only the ninth case of primary SFT of the female genital tract. The tumor presented as a 60-mm, well-circumscribed, painless lump and comprised bland spindle cells in a collagenized stroma with hypercellular and hypocellular foci. Immunohistochemically, the spindle cells were strongly positive for CD34, Bcl 2, and vimentin, with focal positivity for CD99. Immunohistochemical staining for MNF116, desmin, smooth muscle actin, ER, PR, and S100 was negative. There has been no recurrence after 6 months. We discuss the principal differential diagnoses of spindle cell mesenchymal tumors of the vulva and review the previously published cases of primary SFTs originating in the female genital tract. We also stress the importance of informing clinicians involved in these cases of the potential for an unpredictable clinical outcome.

Immunohistochemistry as a diagnostic aid in cervical pathology

As with biopsies from other sites in the female genital tract, immunohistochemistry is now being increasingly used in cervical pathology as an aid to diagnosis. In this review, I discuss applications of immunohistochemistry in diagnostic cervical pathology with a particular focus on recent developments. It is emphasised that immunohistochemistry is to be used as an adjunct to routine morphological examination and that no marker is totally specific or sensitive for a given lesion. Although much of this review focuses on glandular lesions, the value of markers, such as MIB1 and p16, in the assessment of pre-invasive cervical squamous lesions is discussed. In the broad field of cervical glandular lesions, topics covered include: the value of markers such as MIB1, p16 and bcl-2 in distinguishing adenocarcinoma in situ and glandular dysplasia from benign mimics; markers of mesonephric lesions, including CD10; markers of value in the diagnosis of minimal deviation adenocarcinoma, such as HIK1083; markers of value in distinguishing metastatic cervical adenocarcinoma in the ovary from primary ovarian endometrioid or mucinous adenocarcinoma. Rarely ectopic prostatic tissue occurs in the cervix, which can be confirmed by positive staining with prostatic markers. A panel of markers, comprising oestrogen receptor, vimentin, monoclonal carcinoembryonic antigen and p16, is of value in distinguishing between a cervical adenocarcinoma and an endometrial adenocarcinoma of endometrioid type. Markers of use in the diagnosis of cervical neuroendocrine neoplasms, including small cell and large cell neuroendocrine carcinoma, are discussed. It is stressed that small cell neuroendocrine carcinomas may be negative with most of the commonly used neuroendocrine markers and this does not preclude the diagnosis. p63, a useful marker of squamous neoplasms within the cervix, is of value in distinguishing small cell neuroendocrine carcinoma (p63 negative) from small cell squamous carcinoma (p63 positive) and in confirming that a poorly differentiated carcinoma is squamous in type.

Immunohistochemical and functional biomarkers of value in female genital tract lesions

There has been a marked expansion in the literature pertaining to the use of immunohistochemical markers in female genital tract pathology, especially with regard to diagnosis. This review provides a survey of the antibodies commonly used in the diagnosis of gynecological lesions grouped as to function or type. Prognostic or predictive markers are also discussed where appropriate, although few of these are of value in everyday practice. It is stressed that when immunohistochemistry is used diagnostically, panels of markers provide better information than reliance on a single antibody.