Angiomyofibroblastoma of the female genital tract: analysis of 17 cases including a lipomatous variant

Angiomyofibroblastoma as a rare cause of vulvar mass: A case report and literature review

Key Clinical Message

Angiomyofibroblastoma is a benign soft tissue tumor and a form of genital stromal mesenchymal tumor that primarily affects the vulva. It could possibly affect the reproductive-aged women's lower genital tract (vagina).

Abstract

Angiomyofibroblastoma is a rare benign soft tissue tumor primarily affecting the vulva in reproductive-aged women. We report a 67-year-old female complaining of a painless mass in her right vulva spreading to the right inguinal region over the past 2 years. The first clinical impression was a canal of Nuck hernia, diagnostic laparoscopy was planned to rule hernia out. The vulvar mass was excised, and a histopathology examination revealed Angiomyofibroblastoma.

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.

Surgical excision of giant vulvar angiofibroma: A case report and a review of literature

RATIONALE

Cellular angiofibroma (CA) is a rare tumor of the soft tissue classified as a benign fibroblastic/myofibroblastic tumor. Considering this, the literature regarding CA mainly, but not exclusively, comprises single case reports and case series. Here, we report a case of giant CA of the vulva with comprehensive literature review.

PATIENT CONCERNS

We present a case of a massive vulvar CA arising in 53-year-old woman with no notable medical or surgical history. The mass has grown considerably over time, causing pain and difficult urination, defecation, and movement. The patient had normal regular menstrual cycle with no previous contraception use. Vaginal examination exposed a right-sided large tender vulvar mass with normal-looking vagina.

DIAGNOSES

Pelvic magnetic resonance imaging with contrast revealed a large right vulvar heterogeneously enhancing soft tissue mass measuring 13.1 × 10.9 × 10.7 cm expending the left vulva, with internal and peripheral voids resembling feeding vessels. The mass was surgically removed, and subsequent histopathology showed skin-covered dermal-based lesion composed of fibroblast-like bland and spindle cell proliferation with thin-walled blood vessels of various sizes. Immunohistostaining of CD34 and smooth muscle antigen were both positive, while desmin was found to be negative. A diagnosis of vulvar angiofibroma was made based on the clinical scenario, imaging, and histopathology.

INTERVENTIONS

Mass vulvectomy was performed starting with a circumferential incision at the base of the mass and structural dissection to separate the mass from the vulvar wall. The incision was successfully closed, and subcuticular stitches were applied to the skin.

OUTCOMES

The patient's complaints were significantly relieved with no postoperative complications and the patient is being followed regularly in an outpatient setting.

LESSONS

Due to its extremely benign nature of CA, and the implausible ability of its recurrence, it was decided to surgically excise it. Despite its rarity, it can be readily identified at its earlier stages preventing the vexing and exasperating symptoms accompanied with increased size as mentioned.

Cellular angiofibroma of the vagina: A case report and literature review

BACKGROUND

Cellular angiofibroma (CAF), a rare benign mesenchymal tumor, is histologically characterized by abundant thick-walled vessels with a spindle cell component. As one of the female reproductive system tumors, its clinical and pathological features are not well characterized.

METHODS

A 47-year-old woman presented for the removal of intrauterine device on October 28, 2021, as she had achieved menopause one year back. The patient had no discomfort or awareness of any mass in her vagina. She has history of breast cancer and papillary thyroid cancer. Till date, no progression of thyroid cancer or breast cancer has been observed. Her menstrual cycle was regular, and she had one child delivered vaginally.

RESULTS

Pelvic examination revealed a mass sized 2.5 × 2.0 cm located near the fornix in the upper segment of the left vaginal wall. Thin prep cytologic test (TCT) revealed negative intraepithelial lesion or malignancy (NILM). HPV test was negative and leucorrhea routine inspection cleanliness II degree. No cervical mass was detected by ultrasound examination. The patients underwent the operation for intrauterine device removal plus vaginal tumor resection on November 1, 2021. Postoperative antibiotics (intravenous cefuroxime sodium 0.75 g bid for 1 day) were administered to prevent infection. The patient showed no signs of recurrence at one-month follow-up.

CONCLUSION

In summary, CAF is a rare benign soft tissue tumor. Surgery is the only treatment method, and the definitive diagnosis of CAF is based on histopathological examination of surgical specimen. Long-term follow-up is needed for surveillance of recurrence.

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..

Angiomyofibroblastoma and Potential Mimicking Soft Tissue Tumors That May Occasionally Present in the Retroperitoneum: An Approach to the Differential Diagnosis With Report of an Unusual Index Case Abutting the Kidney

The retroperitoneal soft tissues, extending from the pelvic floor to the level of the diaphragm, are the source of a variety of mesenchymal neoplasms with overlapping features and distinct clinical behaviors, making their distinction of crucial importance. Herein, we report a rare retroperitoneal angiomyofibroblastoma (AMFB) that presented as a right abdominal mass in a 25-year-old woman and that clinically simulated a primary renal carcinoma. The patient underwent complete surgical resection showing a well-circumscribed tumor adjacent to but separate from the right kidney. It was comprised of irregular, often anastomosing islands and cords of plump to spindled cells in a collagenous stroma with numerous thin-walled vessels. The tumor cells clustered around the vessels and admixed with moderate numbers of adipocytes. There was neither significant nuclear atypia nor mitotic activity. Immunohistochemically, the tumor cells showed strong reactivity for desmin, diffuse expression of estrogen and progesterone receptors, retained nuclear expression of retinoblastoma protein, and absent CD34 expression. The immunomorphological features were these of a "lipomatous variant" of AMFB of the retroperitoneum. The occurrence of AMFB in the retroperitoneum is unexpected since it mostly develops in the lower genital tract of young women, making its recognition in this rare location difficult. As a consequence, more common pelvic or retroperitoneal soft tissue neoplasms may represent the primary diagnostic considerations. We, therefore, review a variety of soft tissue tumors occurring in the pelvis/retroperitoneum that, to some degree, may mimic AMFB, and present key findings to assist in accurate diagnosis.

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.

Angiomyofibroblastoma of the Vulva

Angiomyofibroblastoma (AMF) is a rare benign soft-tissue tumor that most frequently affects the lower genital tract of young to middle-aged women. It mainly consists of two components: stromal cells and prominent vasculature. Clinically, it is usually asymptomatic and resembles Bartholin's cyst. Although it is a benign tumor, cases with recurrence and sarcomatous transformation have been reported. Due to the overlapping of histopathological picture, diagnostic perplexity often arises between AMF and aggressive angiomyxoma (AAM). AMF being benign in nature is treated by local excision, whereas AAM is a more infiltrative lesion that has a higher tendency for local recurrence.

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.

Review of 189 Consecutive Female Genital Skin and Mucosal Biopsies Submitted to an Academic Dermatopathology Practice

OBJECTIVES

To describe consecutive vulvar biopsy cases and to create an educational template for pathology trainees and practicing pathologists.

METHODS

We reviewed 189 consecutive biopsies from the female genital area skin and mucosa. We classified them based on etiologies and examined limited clinical information.

RESULTS

We classified diagnoses as squamous intraepithelial neoplasia (21.5%), melanocytic neoplasia (17.9%), lichenoid dermatoses (15.9%), nonlichenoid dermatoses (11.3%), infectious (6.2%), reparative (4.6%), or miscellaneous (22.6%). The miscellaneous diagnoses included common entities (polyps and cysts) and rarer entities (calcinosis cutis, adnexal neoplasms, or basal cell carcinoma) and nonspecific descriptive diagnoses. Clinicians most often included the actual diagnosis in their differential for melanocytic lesions (83%) and least often for inflammatory lesions (32%). However, some cases included a clinical description without a differential diagnosis (14%) or no helpful clinical information (4%). The distribution of whether correct diagnoses were included in the clinical differential was similar between submitting physicians and midlevel providers.

CONCLUSIONS

Understanding squamous and melanocytic pathology and the various lichenoid and other inflammatory diagnoses is critical for signing out female genital tract skin pathology. The cases examined in this report can serve as an educational template for trainees and practicing pathologists.

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.

Laparoscopic total extraperitoneal treatment for a hydrocele of the canal of Nuck located entirely within the inguinal canal: A case report

A 43-year-old woman was diagnosed with a hydrocele of the canal of Nuck, for which laparoscopic total extraperitoneal excision was successfully undertaken. The hydrocele was located entirely within the inguinal canal and was barely visible at the internal inguinal ring, even with strong retraction. The inferior epigastric vessels were at risk of injury secondary to excessive tension when retracting the round ligament. To overcome these problems, the hydrocele was approached from the medial side of the inferior epigastric vessels across the transversalis fascia. This approach allowed us to reach the distal end of the hydrocele and avoid excessive traction on the vessels. Thus, a hydrocele of the canal of Nuck can be addressed successfully with minimally invasive laparoscopic total extraperitoneal excision. Approaching the hydrocele from the medial side of the inferior epigastric vessels across the transversalis fascia may be useful.

Cellular angiofibroma in the hypopharynx: A case report

RATIONALE

Cellular angiofibroma is a rare benign mesenchymal tumor which mostly occurs in the superficial soft tissues of the genital region. Occurrence in the head and neck region is extremely rare. To our knowledge, this is the first case of cellular angiofibroma arising in the hypopharynx.

PATIENT'S CONCERNS

A 54-year-old male complained of a mass moving through his throat for 1 month. A tumor was found in the right lateral wall of the pharyngeal at the level of the epiglottis by laryngoscope. Magnetic resonance imaging confirmed the presence of a mass in the right lateral pharyngeal area. A benign tumor was suspected based on the clinical symptoms and imaging findings.

DIAGNOSIS

A supporting laryngoscope was performed under general anesthesia and the lesion was resected. Immunohistochemical analysis revealed cellular angiofibroma.

INTERVENTIONS

The patient underwent surgical excision of the lesion.

OUTCOMES

Thus far, no recurrence has been observed 6 months after excision.

LESSONS

Cellular angiofibroma located in the lateral pharyngeal is rare; however, immunohistochemical staining is helpful for its diagnosis. Treatment is relatively simple and requires local excision and follow-up.

Fibroepithelial Stromal Polyp of the Vulva: Case Report and Review of Potential Histologic Mimickers

Vulvar tumors arising from submucosal connective tissue, some of which exhibit hormonal responsiveness, have many clinical and histologic overlapping characteristics. We present a case of a fibroepithelial stromal polyp arising from the vulva of a 22-year-old female. We review the differential diagnosis with an emphasis on distinguishing features of these uncommon neoplasms. Accurate diagnosis is essential as the extent of surgical resection and risk of local recurrence varies for these tumors.

Vaginal Angiomyofibroblastoma: A Case Report and Review of Diagnostic Imaging

Background

Angiomyofibroblastoma (AMFB) is a benign mesenchymal tumor most commonly found in the female genital tract of premenopausal women. Although rare, AMFB is an important consideration in the differential diagnosis of vulvar and vaginal masses, as it must be distinguished from aggressive angiomyxoma (AA), a locally recurrent, invasive, and damaging tumor with similar clinical and pathologic findings.

Case

We describe a patient with a 4 cm vaginal AMFB and the relevant preoperative radiographic imaging findings.

Conclusion

Preoperative diagnosis of AMFB remains difficult. Common findings on magnetic resonance imaging and transvaginal sonography are described. We conclude that both transvaginal ultrasound and MRI are potentially useful imaging modalities in the preoperative assessment of vulvar and vaginal AMFB, with more data needed to determine superiority of one modality over the other.

Criteria for Risk Stratification of Vulvar and Vaginal Smooth Muscle Tumors: An Evaluation of 71 Cases Comparing Proposed Classification Systems

Accurate risk stratification of smooth muscle tumors (SMTs) is essential for appropriate patient management. Yet, the rarity of SMTs of the vagina and vulva makes development of a prognostically meaningful classification system challenging. While 2 classification methods for vulvar SMTs and 1 for vaginal SMTs have been proposed, it is our experience that many pathologists tend to apply criteria for uterine SMTs when evaluating vulvovaginal tumors. We retrospectively reviewed a large cohort of vulvovaginal SMTs with clinical follow-up and evaluated which method most accurately classified tumors according to patient outcome. A total of 71 tumors, 53 vaginal (75%) and 18 vulvar (25%), from 71 patients were identified. All tumors were centrally examined for degree of cytologic atypia, morphology (spindled, epithelioid, myxoid), mitotic index per 10 high power fields, atypical mitotic figures, tumor cell necrosis, ischemic necrosis, tumor interface (circumscribed or infiltrative) and margin status. Clinical features were recorded for each patient. Follow-up was available for 63 patients (89%), and ranged from 1 to 234 months (median: 64 mo). While site-specific and uterine criteria showed equally excellent sensitivity in classifying smooth muscle neoplasms as leiomyosarcoma according to patient outcome, uterine criteria showed improved specificity relatively to site-specific methods in classifying tumors as nonsarcoma according to patient outcome. We recommend that uterine SMT criteria and nomenclature be adopted for evaluation and classification of vulvovaginal SMTs.

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.

Angiomyofibroblastoma of the vulva diagnosed preoperatively: A case report

A 50-year-old woman (gravida 2, para 2) first noticed a small nodule in the right labium majus 2 years prior to the initial visit to the Hachinohe Red Cross Hospital (Hachinohe, Japan), which had gradually increased in size. On physical examination, a well-circumscribed, elastic, firm, goose egg-sized, subcutaneous mass protruding from the right labium majus was identified. On magnetic resonance imaging (MRI), the lesion was hypointense on T1-weighted images and was well-circumscribed, strongly enhanced and homogeneous on gadolinium-enhanced images, measuring 7.5×4 cm. The same tumor had measured 2.6 cm on an MRI performed 6 years earlier. Based on the clinical course and imaging findings, angiomyofibroblastoma was diagnosed and surgical resection of the tumor was performed. The tumor was well-circumscribed and highly vascular. The intraoperative blood loss was 70 ml. Histopathologically, the tumor cells were concentrated around blood vessels, were spindle-shaped to oval with mild atypia, and were positive for vimentin, desmin, neural cell adhesion molecule (N-CAM), CD-34, estrogen receptor and progesterone receptor, and negative for S-100. Based on these findings, the diagnosis of angiomyofibroblastoma was confirmed. Angiomyofibroblastoma is a benign mesenchymal tumor that occurs in the female external genitalia. Differentiation of this tumor from aggressive angiomyxoma, a fast-growing infiltrative malignancy that occurs in the same region, may be challenging. The diagnosis of angiomyofibroblastoma is usually based on the histopathological findings of the resected specimen. The present case is of value, as the angiomyofibroblastoma was successfully diagnosed preoperatively based on the clinical course and imaging findings.

A Rare Case of Intravesical Angiomyofibroblastoma

OBJECTIVE

To study the first reported case of intravesical angiomyofibroblastoma (AMFB). AMFB is an uncommon benign mesenchymal lesion, mostly described in the lower female genital tract, especially in the vulva and less commonly in the vagina. It is rarely seen in the male genital tract. The importance of this rare neoplasm is related to its potential mimicry of more infiltrative and prognostically less favorable lesions, such as aggressive angiomyxomas, that are found in the same anatomic area.

METHODS

A 26-year-old man presented to us with hematuria. Investigations revealed an intraluminal polypoidal lesion of approximately 92 × 77 × 76 mm within the urinary bladder. Cystoscopy revealed a large well-circumscribed tumor with a pedicle, attached to the inferolateral wall of the bladder near the bladder neck. Open exploration and en bloc excision of the bladder mass was done.

RESULTS

Histopathology and immunohistochemistry (IHC) confirmed the diagnosis of AMFB.

CONCLUSION

AMFB presents as a well-circumscribed superficial mass. Complete excision of the tumor for histopathologic and IHC examination is essential for diagnosis. This rare tumor shows morphologic similarity to some more aggressive tumors with less favorable outcome; hence, it needs to be differentiated from those. IHC is helpful but not always conclusive in the diagnosis of this rare neoplasm. This being the first-ever reported case of intravesical AMFB bears a significant importance. Careful clinical assessment, operative management, and histopathologic examination are of utmost importance in making a precise diagnosis and management of the patient.

Lipomatous angiomyofibroblastoma of the vulva: A case report and review of the literature

Lipomatous angiomyofibroblastoma is extremely rare, with only 16 cases reported to date. We herein describe an additional case arising in the left vulvar region of a 49-year-old woman. The resected 5.3-cm yellowish tumor predominantly consisted of fat cells (85% of the tumor), together with medium- and small-sized vessels, multifocal fibrotic areas and pseudoangiomatous spaces. Spindle, rounded, and/or epithelioid tumor cells proliferated in a nest and/or cord-like pattern, or singly within perivascular fibrous tissues and between fat cells. The tumor cells were positive for vimentin, estrogen receptor, progesterone receptor, B-cell lymphoma 2, and CD10, but were negative for desmin, cytokeratin, epithelial membrane antigen, S-100 protein, human melanoma black 45, C-kit and p40. Ultrastructural examination revealed that these tumor cells exhibited fibroblastic characteristics. Lipomatous angiomyofibroblastoma should be discriminated from other lipomatous tumors, including spindle cell lipoma, angiomyolipoma and cellular angiofibroma containing numerous fat cells.

Angiomyofibroblastoma

We report the clinicopathologic features of eight new cases of angiomyofibroblastoma and review the literature on this recently described entity. Most of our female patients had a vulvar mass that clinically was thought to be a Bartholin's gland cyst. The tumors were well circumscribed and measured 2.9 to 11 cm (mean, 5.2 cm). No recurrences or metastases were observed during follow-up, which ranged from 2 months to 4 years. The tumors were characterized by a myxomatous background with prominent vessels surrounded by plump stromal cells. Immunohistochemically, the stromal cells were reactive for vimentin, but staining for desmin was not always present. Angiomyofibroblastoma should be distinguished from aggressive angiomyxoma because the two entities behave differently. Morphologic and immunohistochemical features should also be considered.

The Spectrum of Canine Cutaneous Perivascular Wall Tumors: Morphologic, Phenotypic and Clinical Characterization

Perivascular wall tumors (PWTs) are defined as neoplasms deriving from mural cells of blood vessels, excluding the endothelial lining. The spectrum of human cutaneous PWT includes glomus tumor, hemangiopericytoma (HEP), myopericytoma, angioleiomyoma/sarcoma, angiomyofibroblastoma, and angiofibroma. The purpose of this study was to revise clinical presentation, cytology, histopathology, and immunohistology of canine cutaneous PWT with cytology typical of canine HEP. Diagnosis was established on the basis of vascular growth patterns (staghorn, placentoid, perivascular whorling, bundles from media) and immunohistology, including 7 smooth muscle markers and the cell membrane ganglioside of unknown origin recognized by the antibody 3G5 (CMG-3G5). Twenty cases were included. Ages ranged from 6 to 13 years; 12 dogs were males and 8 were females, and there was a prevalence of crossbreeds. Tumors arose from a single site with preferential acral location (10/20). Cytology revealed moderate to high cellularity in all cases, cohesive groups of cells (19/20), capillaries (18/20), and bi- to multinucleated cells (18/20). Six myopericytomas, 5 angioleiomyomas, 2 angioleiomyosarcomas, 2 HEP, 1 angiofibroma, and 1 adventitial tumor were identified. A definitive diagnosis was not possible in 3 cases. Smoothelin, heavy caldesmon, desmin, myosin, calponin, and CMG-3G5 were the most valuable markers to differentially diagnose canine PWT. Similar to reports in humans, canine HEP embodied a spectrum of neoplastic entities arising from different vascular mural cells. Before canine PWTs are assimilated into one prognostic category, a consistent classification and characterization of their biology is necessary. As proposed in humans, HEP should also be considered a diagnosis of exclusion in dogs.

Cellular angiofibroma in women: a review of the literature

Cellular Angiofibroma (CA) represents a quite recently described mesenchymal tumour that occurs in both genders, in particular in the vulvo-vaginal region in women and in the inguino-scrotal area in men. The first description of this tumour dates from Nucci et al. article in 1997; since then, the literature reports different reviews and case report of this tumour in both genders, but no article specifically addressing CA treatment and follow-up in women. In this review we collected all 79 published female CA cases, analyzing the clinical, pathological and immunohistochemical features of the tumour.

CA affects women mostly during the fifth decade of life, it is generally a small and asymptomatic mass that mainly arises in the vulvo-vaginal region, although there are reported pelvic and extra-pelvic cases. The treatment requires a simple local excision due to an extremely low ability to recurrent locally and no chance to metastasize. Throughout the immunohistochemical and pathological findings it is also easily possible a differential diagnosis from the other soft tissue tumours which affect the vulvo-vaginal area, such as spindle cell lipoma, solitary fibrous tumour, angiomyofibroblastoma and aggressive angiomyxoma.

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.

Lipomatous variant of angiomyofibroblastoma: a case report and review of the literature

Angiomyofibroblastoma represents a rare, benign mesenchymal tumor with a predilection for the vulvovaginal region. Lipomatous change may occur but rarely comprises a substantial component of the lesion. There are only eight reports in the English language literature describing the lipomatous variant of this tumor. We describe a further lipomatous angiomyofibroblastoma that occurred on the labium majus of a 49-year-old woman. The histopathologic and immunohistochemical features are described, and the collective experience in the literature is reviewed.

Giant pelvic angiomyofibroblastoma: case report and literature review

Angiomyofibroblastoma (AMF) is a rare, benign, soft-tissue tumor, which predominantly occurs in the vulvovaginal region of middle-aged women. It is clinically important to distinguish an AMF from other stromal cell lesions. Here, we report the case of a 32-year-old woman with a rare, giant pelvic AMF, which showed a benign clinical course. The tumor was located in the cul-de-sac of Douglas. It was well demarcated, hypocellular, edematous and composed of spindle-shaped and oval stromal cells aggregating around thin-walled blood vessels. The tumor cells had abundant eosinophilic cytoplasm, and expressed estrogen receptors, progesterone receptors and desmin. Mitotic figures were absent. It is important to distinguish AMFs from aggressive angiomyxomas because both occur at similar sites but show different clinical behaviors. Most AMFs and aggressive angiomyxomas have the same immunohistochemical phenotype. The well-circumscribed borders of AMF are the most important characteristic that distinguish it from aggressive angiomyxomas. AMFs rarely recur after complete surgical excision.

Perineal Nodular Induration (“Biker’s Nodule”)

Perineal nodular induration (PNI) is a fibroblastic pseudotumor that presents almost exclusively in male cyclists. It develops in the soft tissues of the perineum immediately posterior to the scrotum, as a bilateral or single, central or lateralized mass. Although well known to sport medicine specialists, it is a scarcely documented entity in the pathology literature. We present 2 cases of PNI with fine-needle aspiration cytology and immunohistochemistry. They consisted of a paucicellular fibroblastic proliferation containing CD34-reactive spindle and epithelioid cells, small foci of fibrinoid degeneration, numerous blood vessels, and entrapped groups of mature fat cells. Our cases show that the histopathological features of PNI are more varied than those previously described and its immunohistochemical profile is wider. A central cystic focus and a zonal pattern are not consistent features of this entity. The lesional cells can express CD34, a hitherto unreported immunohistochemical finding.

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.

Pedunculated angiomyofibroblastoma of the vulva: case report and review of the literature

Angiomyofibroblastoma (AMFB) is a rare benign mesenchymal tumour that occurs almost exclusively in the vulvovaginal region of women but can also occur occasionally in the inguinoscrotal region of men. It is a well-circumscribed lesion that clinically is often thought to represent a Bartholin's gland cyst and usually does not form a pedunculated mass. To our knowledge, only five cases of vulvar AMFB with pedunculated mass have been reported in the English literature and all cases involving the labia majora and middle-aged women. We report the first case of pedunculated AMFB of the vulva occurring in a young woman of 21 years old and involving the left labia minora. After excluding the most common diseases, pedunculated AMFB should be part of differential diagnosis in the workup of any pedunculated vulvar mass even in young women with a lesion involving the labia minora. We reviewed the literature and summarized all reported cases.

Pseudoangiomatous stromal hyperplasia of the breast in a 10-year-old girl

Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign lesion, characterized by a dense proliferation of stromal mesenchymal cells of myofibroblastic origin forming empty, slitlike channels. The development of PASH is subject to hormonal influence and is most commonly seen in premenopausal women. In adolescent patients, PASH is rarely reported. Here we report a case of PASH presenting in a 10-year-old girl. After the presentation and inconclusive radiographic findings, incisional biopsy revealed a soft nodule with histopathologic features characteristic of PASH. Immunoperoxidase studies showed positive immunoreactivity for CD34 and bcl-2 and negative immunoreactivity for CD31 and desmin, supporting the diagnosis of PASH. Because of the benign nature of the lesion, excisional biopsy was deferred to minimize damage to the patient's developing breast. To our knowledge, this case represents the youngest female patient with unequivocal PASH in reported literature.

Haematoma in a hydrocele of the canal of Nuck mimicking a Richter's hernia

We report a haematoma in a hydrocele of the canal of Nuck in a 69-year-old female. She presented with a right-sided groin swelling, the differential for which included an irreducible inguinal hernia or haematoma given her aspirin and clopidegrel use. Successful treatment involved evacuation of the haematoma with excision of the sac. Despite a high index of suspicion for a haematoma, these swellings should ideally be explored given the potential for co-existence of a hernia.

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.

Angiomyofibroblastoma of the spermatic cord: a case report

Introduction

Angiomyofibroblastoma is a benign soft tissue tumor with tendency to arise in the vulva.

Case presentation

We report a 36-year-old Greek Caucasian man presenting with a left inguinal painless mass. This is the second case of angiomyofibroblastoma of the spermatic cord. At operation, a 4.5 cm well-circumscribed solid tumor was found adherent to the spermatic cord. The tumor consisted of spindle-shaped cells proliferating in short fascicles between numerous medium-sized blood vessels with thin and hyalinized walls. Neoplastic cells had eosinophilic cytoplasm with neither mitotic figures nor nuclear atypia. The stroma included abundant mast cells and few mature lypocytes. Immunostaining showed positivity for vimentin, CD34, desmin and smooth muscle actin. Our patient was treated by simple excision and was followed up for five years with clinical examination and ultrasonography, revealing no evidence of local recurrence or metastasis.

Conclusion

This unusual neoplasm should be distinguished from aggressive angiomyxoma and other myxoid malignant tumors with widespread metastatic potential.

Mesenchymal Lesions of the Lower Genital Tract

A variety of site-specific mesenchymal lesions of the lower genital tract may occur, which are often diagnostically challenging because of their morphologic overlap. Some of this morphologic homogeneity presumably stems from a potentially shared origin from the specialized superficial stroma of the distal female genital tract. Despite shared appearances, morphologic distinction remains the gold standard for diagnosis of most of these lesions, as immunoperoxidase staining is often not helpful in their distinction.

Angiomyofibroblastoma: a rare vulvar tumor

INTRODUCTION

Angiomyofibroblastoma is a rare, benign mesenchymal tumor that occurs mainly in the vulval region of middle age (35-45 years) women.

CASE

We describe a 41-year-old woman, presenting with a 10-cm right vulvar mass and persistent perineal pain lasting 1 month. A surgical excision of the lesion was performed and a large mass with an intact capsule was sent for pathological examination. The results indicated angiomyofibroblastoma.

CONCLUSION

The differential diagnosis between angiomyofibroblastoma (AMF) and aggressive angiomyxoma (AAM) is very important because prognoses are not the same. AMF is a well-circumscribed lesion, with a weak risk of local non-destructive recurrence. AAM is a locally aggressive and infiltrative neoplasm, with a high risk of local aggressive recurrence. Wide excision with a rim of normal tissue is recommended in all cases of vulvar tumors.