Chromosomal translocation t(8;12) induces aberrant HMGIC expression in aggressive angiomyxoma of the vulva

Aggressive angiomyxoma of female pelvis and perineum: Retrospective study of 17 cases

OBJECTIVE

Aggressive angiomyxoma is an uncommon mesenchymal neoplasm characterized by a high recurrence rate, usually observed in the lower genital tract of women during their reproductive age.

STUDY DESIGN

Seventeen cases of aggressive angiomyxoma confirmed by pathology from January 2007 to December 2021 in Beijing Chao-yang Hospital were included. We collected clinical data and summarized the clinical and immunohistochemical features.

RESULTS

All seventeen included patients were females, aged between 23 and 57 years (mean, 37.7 years; median, 42 years). Fourteen patients were newly diagnosed and three were recurrent. The tumors were located in vulva (58.8 %), vagina (23.5 %), buttock (11.8 %), and cervix (5.9 %). The tumors size were 2 to 15 cm in greatest dimension (mean 8 ± 4.4 cm, median 6 cm). Follow-up data was available for nine patients, which ranged from 25 to 124 months (mean, 82 months; median, 80 months). At the end of follow-up, no other recurrence or metastasis was reported. Immunohistochemical analysis showed immunoreactive for estrogen (10/11) and progesterone (8/11) receptor, desmin (6/8), smooth muscle actin (4/10), and vimentin (4/4), S-100 (1/8) and CD34 (1/7). The Ki67 level was less than 5 % in five cases.

CONCLUSIONS

AAM is a hormone-sensitive, distinct rare mesenchymal neoplasm with high incidence of local recurrence. Surgery is the preferred treatment, with complete resection being an essential prerequisite for minimizing the risk of recurrence.

Aggressive Angiomyxoma of the Lower Female Genital Tract: A Review of the MITO Rare Tumors Group

Aggressive angiomyxoma (AAM) is a rare, locally aggressive, myxoid mesenchymal neoplasm primarily found in the pelvic and perineal regions of young adult females. It is a slow growing and locally infiltrating tumor. Preoperative diagnosis is difficult due to the rarity of these tumors and absence of characteristic signs and symptoms. The primary management is tumor excision. Incomplete excision is common because of the infiltrating nature of the neoplasm and absence of a definite capsule. Other non- surgical modalities have been employed, such as radiotherapy, embolization, GnRH analogues or other anti-estrogenic agents. Local relapses occur in 30-40% of the cases, and often appear many years (sometimes decades) after the first excision. Occasional distant metastasis has also been reported. A limited number of cases have been reported in the literature, mostly in the form of small case series or isolated case reports. Therefore, the aim of this paper by a team of experts from the MITO rare tumors group is to review clinical findings, pathologic characteristics and outcome of patients affected by this rare condition in order to be able to offer up-to-date guidance on the management of these cases.

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.

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.

Plexiform fibromyxoma: Review of rare mesenchymal gastric neoplasm and its differential diagnosis

Plexiform fibromyxoma (PF) is a very rare mesenchymal neoplasm of the stomach that was first described in 2007 and was officially recognized as a subtype of gastric mesenchymal neoplasm by World Health Organization (WHO) in 2010. Histologically, PF is characterized by a plexiform growth of bland spindle to ovoid cells embedded in a myxoid stroma that is rich in small vessels. The lesion is usually paucicellular. While mucosal and vascular invasion have been documented, no metastasis or malignant transformation has been reported. Its pathogenesis is largely unknown and defining molecular alterations are not currently available. There are other mesenchymal tumors arising in the gastrointestinal tract that need to be differentiated from PF given their differing biologic behaviors and malignant potential. Histologic mimics with spindle cells include gastrointestinal stromal tumor, smooth muscle tumor, and nerve sheath tumor. Histologic mimics with myxoid stroma include myxoma and aggressive angiomyxoma. Molecular alterations that have been described in a subset of PF may be seen in gastroblastoma and malignant epithelioid tumor with glioma-associated oncogene homologue 1 (GLI1) rearrangement. The recent increase in publications on PF reflects growing recognition of this entity with expansion of clinical and pathologic findings in these cases. Herein we provide a review of PF in comparison to other mesenchymal tumors with histologic and molecular resemblance to raise the awareness of this enigmatic neoplasm. Also, we highlight the challenges pathologists face when the sample is small, or such rare entity is encountered intraoperatively.

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.

Retrospective analysis of clinicopathological features and prognosis for aggressive angiomyxoma of 27 cases in a tertiary center: a 14-year survey and related literature review

PURPOSE

Aggressive angiomyxoma (AAM) is a rare and often misdiagnosed tumor that is characterized by frequent local recurrences. This study aimed to investigate the clinicopathological characteristics, surgical experiences, and prognosis for aggressive angiomyxoma to improve the accuracy of diagnosis and develop treatment strategies for decreasing recurrence rates.

METHODS

Clinicopathological data and follow-up information for 27 patients with AAM diagnosed and treated at the Shengjing Hospital of China Medical University between January 2006 and October 2019 were retrospectively analyzed.

RESULTS

The median age at disease onset among 27 patients was 39 years. The male to female ratio was 1:4.4. Painless and slow-growing mass was the most common symptom. Masses occurring in the perineum and pelvic cavity accounted for 81.5% (22/27). All of the 27 patients underwent surgical treatment. Surgical approaches included transperineal and transvaginal resection. Large pelvic masses were treated with combined abdominoperineal surgery. The postoperative recurrence rate was 37%. Kaplan-Meier survival analysis revealed that 5-year progression-free survival (PFS) rate was 64.4% and the median PFS was 132.0 ± 29.6 (95% CI 72.9-190.1). Multivariate Cox proportional analysis found that surgical margin is an independent prognostic factor for PFS (P = 0.018). None of the patients experienced distant metastasis.

CONCLUSIONS

Clinical manifestations of AAM are non-specific. Laboratory testing, imaging examinations, and immunohistochemistry are helpful for diagnosis and differential diagnosis. Surgical approach can be determined according to the relationship between the tumor and adjacent organs and infiltration degree. The development of personalized treatment strategies should aim to achieve a complete resection on the premise of preserving the structure and function of important organs to maintain patient quality of life.

Radiomic features from MRI distinguish myxomas from myxofibrosarcomas

BACKGROUND

Myxoid tumors pose diagnostic challenges for radiologists and pathologists. All myxoid tumors can be differentiated from each other using fluorescent in-situ hybridization (FISH) or immunohistochemical markers, except for myxomas and myxofibrosarcomas. Myxomas and myxofibrosarcomas are rare tumors. Myxomas are benign and histologically bland, whereas myxofibrosarcomas are malignant and histologically heterogenous. Because of the histological heterogeneity, low grade myxofibrosarcomas may be mistaken for myxomas on core needle biopsies. We evaluated the performance of T1-weighted signal intensity (T1SI), tumor volume, and radiomic features extracted from magnetic resonance imaging (MRI) to differentiate myxomas from myxofibrosarcomas.

METHODS

The MRIs of 56 patients (29 with myxomas, 27 with myxofibrosarcomas) were analyzed. We extracted 89 radiomic features. Random forests based classifiers using the T1SI, volume features, and radiomic features were used to differentiate myxomas from myxofibrosarcomas. The classifiers were validated using a leave-one-out cross-validation. The performances of the classifiers were then compared.

RESULTS

Myxomas had lower normalized T1SI than myxofibrosaromas (p = 0.006) and the AUC using the T1SI was 0.713. However, the classification model using radiomic features had an AUC of 0.885 (accuracy = 0.839, sensitivity = 0.852, specificity = 0.828), and outperformed the classification models using T1SI (AUC = 0.713) and tumor volume (AUC = 0.838). The classification model using radiomic features was significantly better than the classifier using T1SI values (p = 0.039).

CONCLUSIONS

Myxofibrosarcomas are on average higher in T1-weighted signal intensity than myxomas. Myxofibrosarcomas are larger and have shape differences compared to myxomas. Radiomic features performed best for differentiating myxomas from myxofibrosarcomas compared to T1-weighted signal intensity and tumor volume features.

Novel HMGA2-YAP1 fusion gene in aggressive angiomyxoma

We describe a case of a 44-year-old woman with locally advanced aggressive angiomyxoma with a novel translocation high-mobility group AT-hook 2-yes-associated protein 1 (HMGA2-YAP1) fusion, implying a t(11;12)(q22.1;q14.3) translocation. She was started on gonadotropin-releasing hormone agonist injection and an aromatase inhibitor for persistent disease, which responded to treatment; she was subsequently treated with radiation before a more definitive operation was conducted. This case report indicates that HGMA2-YAP1-translocated aggressive angiomyxoma is responsive to oestrogen antagonism and hopefully will allow for the development of diagnostics useful for this rare but often morbid neoplasm. This case also highlights the importance of appropriate workup of a soft tissue mass.

A giant aggressive angiomyxoma of vulva in a young woman: A case report

RATIONALE

Aggressive angiomyxoma (AAM) is a rare and benign invasive mesenchymal stromal tumor predominantly in women at reproductive age. AAM tends to relapse locally and should be differentially diagnosed from other mesenchymal tumors.

PATIENT CONCERNS

We report here a rare case of massive vulvar AAM in a 22-year-old Chinese woman with left labia majora mass with ulcer.

DIAGNOSES

The diagnosis "aggressive angiomyxoma of vulva" was based on clinicopathologic and immunohistochemical features.

INTERVENTIONS

A surgery with local excision of the mass was performed.

OUTCOMES

The patient was discharged 12 days after the surgery. There was no AAM recurrence or metastasis in a period of 12-month follow-up.

LESSONS

The vulvar AAM is a benign and aggressive mesenchymal tumor. In this case, we present the diagnosis, treatment, and prognosis for vulvar AAM. The tumor was removed completely by the surgery, but a long-term follow-up is requisite for surveilling on recurrence.

A Case Report of Aggressive Angiomyxoma in Pregnancy: Do Hormones Play a Role?

Aggressive angiomyxoma is a rare, locally invasive tumor that generally affects the perineum and pelvis of reproductive age females. Aggressive angiomyxoma is often misdiagnosed, resulting in the delay of the treatment. Case reports show increased growth of the tumor during pregnancy, thus suggesting a hormonal dependency. We report this rare condition in a 29-year-old primigravid female with a growing mass on the right labium majus at 20 weeks' gestation. The patient also developed a smaller mass on the left labium majus at 37 weeks' gestation. The patient underwent a primary cesarean section with resection of the right labial mass, with a final diagnosis of aggressive angiomyxoma. The lesion on her left labium majus resolved spontaneously postpartum. This case report supports a hormonal involvement in this tumor.

Analysis of MDM2 Amplification in 43 Endometrial Stromal Tumors: A Potential Diagnostic Pitfall

MDM2 amplification is known to occur in a variety of neoplasms and its detection by fluorescence in situ hybridization is helpful in distinguishing well-differentiated and dedifferentated liposarcoma from classic lipoma. We recently evaluated a mesenteric mass initially diagnosed as dedifferentiated liposarcoma, largely due to the neoplasm's myxoid morphology and MDM2 expression by immunohistochemistry, from a 46-yr-old woman with a history of uterine low-grade endometrial stromal sarcoma (LG-ESS) with a JAZF1 rearrangement. Our workup of the mesenteric mass revealed a JAZF1 rearrangement and a revised diagnosis of metastatic LG-ESS with myxoid change was rendered. Retrospective testing of the mesenteric mass was negative for MDM2 amplification, an uncommon, but known diagnostic pitfall in MDM2 expression by immunohistochemistry. As MDM2 amplification is not specific for the diagnosis of liposarcoma, we investigated its occurrence in 43 cases of endometrial stromal tumors: 14 uterine LG-ESS, 11 metastatic or recurrent uterine LG-ESS, 8 undifferentiated uterine sarcomas, 5 endometrial stromal nodules, and 4 high-grade ESS with YHWAE rearrangement. In addition, 40 of the 43 cases had previously undergone fluorescence in situ hybridization analysis of JAZF1, PHF1, and YHWAE. Two of the 43 cases (5%) had MDM2 amplification: one was a uterine LG-ESS (JAZF1 rearrangement) and the other was a undifferentiated uterine sarcoma (polysomy intact JAZF1, PHF1, and YHWAE), both metastatic to the lung. Both cases positive for MDM2 amplification showed MDM2 expression by immunohistochemistry. At last follow-up, both patients had died of disease (19 and 60 mo). Our study is the first to demonstrate MDM2 amplification in endometrial stromal tumor. Awareness of MDM2 amplification in endometrial stromal tumor is critical; particularly in locations more common to liposarcoma, to avoid diagnostic errors.

Intravenous leiomyomatosis: an unusual intermediate between benign and malignant uterine smooth muscle tumors

Intravenous leiomyomatosis is an unusual smooth muscle neoplasm with quasi-malignant intravascular growth but a histologically banal appearance. Herein, we report expression and molecular cytogenetic analyses of a series of 12 intravenous leiomyomatosis cases to better understand the pathogenesis of intravenous leiomyomatosis. All cases were analyzed for the expression of HMGA2, MDM2, and CDK4 proteins by immunohistochemistry based on our previous finding of der(14)t(12;14)(q14.3;q24) in intravenous leiomyomatosis. Seven of 12 (58%) intravenous leiomyomatosis cases expressed HMGA2, and none expressed MDM2 or CDK4. Colocalization of hybridization signals for probes from the HMGA2 locus (12q14.3) and from 14q24 by interphase fluorescence in situ hybridization (FISH) was detected in a mean of 89.2% of nuclei in HMGA2-positive cases by immunohistochemistry, but in only 12.4% of nuclei in negative cases, indicating an association of HMGA2 expression and this chromosomal rearrangement (P=8.24 × 10(-10)). Four HMGA2-positive cases had greater than two HMGA2 hybridization signals per cell. No cases showed loss of a hybridization signal by interphase FISH for the frequently deleted region of 7q22 in uterine leiomyomata. One intravenous leiomyomatosis case analyzed by array comparative genomic hybridization revealed complex copy number variations. Finally, expression profiling was performed on three intravenous leiomyomatosis cases. Interestingly, hierarchical cluster analysis of the expression profiles revealed segregation of the intravenous leiomyomatosis cases with leiomyosarcoma rather than with myometrium, uterine leiomyoma of the usual histological type, or plexiform leiomyoma. These findings suggest that intravenous leiomyomatosis cases share some molecular cytogenetic characteristics with uterine leiomyoma, and expression profiles similar to that of leiomyosarcoma cases, further supporting their intermediate, quasi-malignant behavior.

Aggressive angiomyxoma of the vulva: case report

Female patient, 42-years-old, complaining of difficulty in urinating and swelling in the vulvar area for one year. Her gynecological examination showed extensive injury in the vulvar region and the biopsy done was inconclusive. The removal of the lesion was conducted. After the procedure, the patient remains free of recurrence for 15 months. This case highlights the need to consider angiomyxoma in the differential diagnosis for tumors of unknown cause in the vulvar region.

Aggressive angiomyxoma of the vulva: a bizarre perineal lesion

Introduction. Aggressive angiomyxoma is a rare, slowly growing, and benign tumour of mesenchymal origin, which affects women of reproductive age and is associated with a high risk of local recurrence. Case Presentation. A case of a 47-year-old white female is presented herein, with a large polypoid, gelatinous mass on the right labia majora, measuring 26 × 21 × 6 cm. Histopathologically, the lesion was composed of spindle and stellate-shaped cells embedded in a myxoid matrix. Another specific feature was the presence of variable-sized thin-walled capillaries and thick-walled vascular channels. The patient underwent wide local excision of the tumour with clear margins and developed local recurrence 18 months later. Discussion. Aggressive angiomyxoma of the vulva needs to be distinguished from benign myxoid tumors with a low risk of local recurrence as well as from malignant myxoid neoplasms. Usually wide local excision with tumour-free margins and occasionally hormonal manipulation is the treatment of choice.

Targeted genomic analysis of Müllerian adenosarcoma

Müllerian adenosarcoma (MA) is a rare mixed mesenchymal tumour of the female genital tract, composed of malignant stroma and benign-appearing epithelium. Sarcomatous overgrowth (SO) is the only established histological variable associated with higher stage and shorter survival. Specific molecular or immunohistochemistry (IHC) tools for the diagnosis of MA are lacking. Our goal was to study genomic mutations and copy number variations (CNVs) in MA to understand better its pathobiology, and develop specific diagnostic and prognostic tools. DNA was extracted from 20 samples of MA from 18 subjects (12 without SO and 6 with SO), including two in which areas of both typical MA histology and SO were independently tested. Samples were analysed using a targeted next-generation sequencing assay interrogating exonic sequences of 275 cancer genes for mutations and CNVs as well as 91 introns across 30 genes for cancer-associated rearrangements. The mean number of mutations in MA with SO (mean 9.7; range 3-14) did not differ significantly from that in MA without SO (mean 9.6; range 5-16). MA with SO had significantly higher mean numbers of gene-level CNVs (24.6) compared to MA without SO (5; p = 0.0002). The most frequent amplification involved MDM2 and CDK4 (5/18; 28%), accompanied by focal CDK4 and MDM2 and diffuse HMGA2 expression using immunohistochemistry. MYBL1 amplification was seen in 4/18 (22%), predominantly in SO. Alterations in PIK3CA/AKT/PTEN pathway members were seen in 13/18 (72%). Notably, TP53 mutations were uncommon, present in only two cases with SO. Three out of 18 (17%) had mutations in ATRX, all associated with SO. No chromosomal rearrangements were identified. We have identified a number of recurrent genomic alterations in MA, including some associated with SO. Although further investigation of these findings is needed, confirmation of one or more may lead to new mechanistic insights and novel markers for this often difficult-to-diagnose tumour.

HMGA2 and high-grade serous ovarian carcinoma

HMGA2, the High Mobility Group A2 gene, plays a very important role in fetal development and carcinogenesis. As an oncofetal gene, it is upregulated in tumors of both epithelial and mesenchymal tissue origin. Chromosomal translocations of HMGA2 are common in mesenchymal tumors, whereas the regulatory mechanisms of HMGA2 in malignant epithelial tumors are much more complex. As an architectural transcription factor, it is involved in multiple biological pathways by targeting different downstream genes in different cancers. HMGA2 is upregulated in both the early and late stages of high-grade serous ovarian carcinoma (HGSOC) and, according to The Cancer Genomic Atlas, is among a signature of genes overexpressed in ovarian cancer. Recent identification of miR-182 as a mediator of BRCA1 and HMGA2 deregulation in ovarian cancer cells may guide us toward a better understanding of the roles of HMGA2 in ovarian carcinogenesis. In this article, we will review recent developments and findings related to HMGA2, including its regulation, oncogenic properties, major functional pathways associated with the tumorigenesis of HGSOC, and its potential role as a biomarker for clinical application.

Aggressive angiomyxoma of the vulva: case report and literature review

Aggressive angiomyxoma is a rare softtissue tumour, typically occurring in the female pelvis and carrying a high risk of local infiltration and relapse. Surgery remains the first line of treatment, however some adjuvant treatments, such as gonadotrophin-releasing hormone (GnRH) agonists, have been used for primary treatment and for treatment against tumour recurrence. We describe a case of vulvar aggressive angiomyxoma in a 31-year old woman who underwent surgical excision of the tumour. Diagnosis was made on the basis of histopathological examination and positive immunohistochemical staining with oestrogen and progesterone receptors. Postsurgery, a GnRH agonist (3.75 mg triptorelin) was injected intramuscularly every month for 3 months to prevent tumour recurrence and, to date, no relapse has been observed. Whether treatment is with surgery, hormone therapy or both, it is clear that aggressive angiomyxoma requires close, long-term follow-up to monitor for disease recurrence and that the individualization of each case is essential for adequate management.

Value and limitation of immunohistochemical expression of HMGA2 in mesenchymal tumors: about a series of 1052 cases

The high mobility group A (HMGA2) gene encodes a protein that alters chromatin structure and regulates the transcription of many genes; it is implicated in both benign and malignant neoplasias, but its rearrangements are a feature of development of several mesenchymal tumors. Given its implication in these tumors and particularly adipocytic tumors, and the availability of antibodies usable on paraffin-embedded tissues, we evaluated the immunohistochemical expression of this gene in a series of 1052 mesenchymal tumors. The objective was to define the value and limitations of HMGA2 immunohistochemical expression for histotyping, and compare with molecular data reported in the literature. We thus analyzed 880 cases on tissue microarray and 182 cases on whole sections (211 adipocytic tumors, 628 sarcomas, 213 benign mesenchymal tumors, and 10 normal adipose tissues). A nuclear immunostaining was detected in 86% of conventional and intramuscular lipomas, in 86% of well-differentiated liposarcomas and in 67% of dedifferentiated liposarcomas, as opposed to 16% of other benign adipose tumors and to 15% of non-well-differentiated liposarcoma/dedifferentiated liposarcoma sarcomas. Among benign mesenchymal tumors and lesions, it was detected in 90% of nodular fasciitis and in 88% of benign fibrous histiocytomas with respective specificities of 85 and 100%, and in 90% of aggressive angiomyxoma, contrary to other vulvovaginal tumor types, which expressed HMGA2 only rarely. The normal adipose tissue was always negative for HMGA2. Although not specific, immunohistochemical detection of the HMGA2 protein is helpful for the distinction of normal adipose tissue from well-differentiated lesions, particularly on biopsy or on re-excision. It is less sensitive than MDM2/CDK4 for dedifferentiated liposarcomas diagnosis, but it appears more specific to distinguish dedifferentiated liposarcomas from other poorly differentiated sarcomas. Finally, and may be more importantly, HMGA2 is useful for the diagnosis of benign fibrous histiocytoma, nodular fasciitis and vulvovaginal benign mesenchymal tumors.

Clinical experiences on aggressive angiomyxoma in China (report of 93 cases)

OBJECTIVE

To discuss the clinical experiences of aggressive angiomyxoma (AAM) by summarizing clinical information of patients with this disease in China.

METHODS

Chinese articles concerning AAM were retrospectively reviewed and analyzed.

RESULTS

A total of 93 cases in 44 well-documented articles had been reported, among which 11 were male and 82 were female, with a male to female ratio of 1:7.45. The age of the females varied from 14 to 55 years (mean [SD], 37.17 [10.39] years; median, 38.5 years), whereas that of the males ranged from 15 to 65 years (mean [SD], 44.75 [17.61] years; median, 55 years), which was significantly higher than that of the females (t = 2.082, P = 0.041). The most common sites were the perineum in females and the scrotum in males. None of the cases could be accurately diagnosed as AAM preoperatively. The mean minimum diameter of the tumors was 4.62 (3.51) cm, and the maximum was 9.12 (8.23) cm. All the specimens showed typical pathological features of AAM as reported previously. Immunohistochemistry indicated that AAM tended to be strongly positive for vimentin, smooth-muscle actin, and CD34 but mostly negative for S-100 and CD68. The duration of the postoperative follow-up was 3 to 96 months (mean [SD], 28.5 [18.86] months; median, 9.5 months) in 44 cases, with a recurrence rate of 31.82%.

CONCLUSIONS

Aggressive angiomyxoma must be considered in the differential diagnosis of any female with an asymptomatic perineal mass. A complete margin-free excision should be achieved to avoid recurrence. Long-term follow-up is quite necessary because of the high rate of local recurrence.

Aggressive angiomyxoma of larynx: case report and literature review

Objective:

We report the second known case of aggressive angiomyxoma of the larynx.

Method:

Case report and a review of the world literature concerning angiomyxoma of the larynx and recent advances in the immunohistochemical, cytogenic and clinical study of its female pelvic counterpart.

Results:

Aggressive angiomyxoma is a rare mesenchymal tumour originally thought only to occur in the female pelvis and peritoneum, or rarely in the male genital tract. A 47-year-old man presented with a one-month history of dysphonia. He was found to have a supraglottic mass on endoscopic examination, and underwent a laryngofissure approach excision biopsy and covering tracheostomy. Histological analysis showed a characteristic proliferation of spindle cells widely separated by loose, myxoid stroma with a prominent vascular component. Aggressive angiomyxoma was diagnosed.

Conclusion:

To our knowledge, this is the second report in the world literature of aggressive angiomyxoma of the larynx. Comparison with the female pelvic counterpart facilitates diagnosis, aided by recent advances, and suggests that complete surgical excision with a wide margin is the treatment of choice.

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.

Cytogenetics of Mesenchymal Tumors of the Female Genital Tract

A great diversity of chromosome alterations have been reported in mesenchymal tumors of the female genital tract, particularly in the uterus. Some of these alterations specifically identify a certain tumor type. Cytogenetic studies on benign proliferations have not only demonstrated clonal chromosome changes, but have also pointed out clustering of aberrations to specific chromosome regions. For example, distinct cytogenetic subgroups have been described in uterine leiomyomas with overlapping histologic features. These findings may ultimately correlate with specific parameters, such as course of the disease, response to therapy, and recurrence. Moreover, such data may give a clue to an understanding of the biologic basis for distinctive behavior of benign versus malignant mesenchymal proliferations. No specific chromosomal abnormalities have been described in malignant mesenchymal tumors, with the exception of low-grade endometrial stromal sarcomas. This article reviews the information currently available on genetic changes in mesenchymal tumors of the female genital tract and, more specifically, those reported in the uterus, where they have been more frequently studied.

Molecular Genetics of Mesenchymal Tumors of the Female Genital Tract

Mesenchymal tumors of the female genital tract are a heterogeneous group of neoplasms that can be classified based on cellular differentiation into 3 main groups: smooth muscle tumors, endometrial stromal tumors, and other differentiated and undifferentiated tumors. Genomic analysis techniques have revealed important genetic aberrations such as the t(7;17) translocation, resulting in JAZF1-JJAZ1 gene fusion, characteristic of endometrial stromal tumors. These analyses have demonstrated genetic complexity and heterogeneity in many mesenchymal tumor types. This article focuses on current understanding of the molecular genetics of mesenchymal tumors of the female genital tract, with emphasis on diagnostic and prognostic molecular features.

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.

Myxomatous neoplasms in the perineal region of baboons

BACKGROUND

In baboons, Papio sp. neoplasms tend to affect the hematopoietic system most commonly, with rare documentation of myxomatous neoplasms. In contrast, women can develop myxomatous masses within deep peripelvic tissues with some frequency during their reproductive years.

METHODS

We have identified and examined, retrospectively, myxomatous perineal masses in twelve female baboons within one research facility and compared their histopathologic, immunohistochemical and electron microscopic features to their human variants.

RESULTS

Our results indicate that these myxomatous neoplasms, in humans and non-human primates, share common features.

CONCLUSION

Further research, particularly molecular genetic analysis, may be needed to identify the baboon as a true animal model for myxomatous perineal neoplasms.

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.

Aggressive angiomyxoma with t(12;21) and HMGA2 rearrangement: report of a case and review of the literature

Conventional cytogenetic analysis of an aggressive angiomyxoma of the rectal wall of a 72-year-old woman revealed a translocation between the long arms of chromosomes 12 and 21, with the karyotype 46,XX,t(12;21)(q15;q21.1). Involvement of the HMGA2 gene locus (12q15) was confirmed by fluorescence in situ hybridization using an HMGA2 breakpoint flanking probe set performed on metaphase and interphase cells from an in situ culture of fresh lesional tissue. Karyotypic rearrangements of 12q13 approximately q15 are considered recurrent in aggressive angiomyxoma, although reported in only five previous cases. Translocation partner chromosome 21 is unique to the present case.

Frequency and characterization of HMGA2 and HMGA1 rearrangements in mesenchymal tumors of the lower genital tract

Mesenchymal tumors of the lower genital tract predominantly occur in women of reproductive age and are mainly represented by aggressive angiomyxoma (AAM) and angiomyofibroblastoma (AMF). Whether these tumors are different phenotypic expressions of the same biological entity is still debatable. Genetic rearrangements of HMGA2 have been reported in a few cases of AAM but its frequency and clinicobiological implications have not been studied systematically. We evaluated 90 cases of mesenchymal tumors of the lower genital tract that comprised 42 AAMs, 18 AMFs, 6 cellular angiofibromas, 5 fibroepithelial stromal polyps, 15 genital leiomyomas, 3 superficial angiomyxomas, and 1 spindle cell lipoma. Fluorescence in situ hybridization was used to identify rearrangements of HMGA2 and its homologue HMGA1. HMGA2 rearrangements were identified in 14 AAMs (33%) and in 1 vaginal leiomyoma. All other tumors were negative for HMGA2 rearrangements. HMGA1 rearrangement was not found in any of the cases. RT-PCR confirmed transcriptional upregulation of HMGA2 only in tumors with HMGA2 rearrangements. Standard cytogenetic analyses were performed in two AAMs and one AMF. One AAM had a t(1;12)(p32;q15); the other tumors had normal karyotypes. Mapping and sequence analysis of the breakpoint showed fusion to the 3' untranslated region of HMGA2 to genomic sequences derived from the contig NT 032977.8 on chromosome 1p32. Our findings support the hypothesis that AAM and AMF are distinct biological entities. The diagnostic usefulness of HMGA2 rearrangements to differentiate between AAM and other tumors of the lower genital tract may be limited due to the their low frequency.

Aggressive Angiomyxoma of the Vulva With a Sole t(5;8)(p15;q22) Chromosome Change

Aggressive angiomyxoma of the vulva is uncommon and the pathogenesis remains unclear. Recently, a few cytogenetic studies demonstrated chromosomal abnormalities in aggressive angiomyxoma of the vulva. A 45-year-old Japanese woman complaining of right-side vulva tumor measuring 3 cm in diameter was referred to our hospital. The mass was located at the right side of the rectovaginal septum and was closely adherent to the rectal serosa and the levator muscle ani. The tumor was completely resected. A pathological examination demonstrated aggressive angiomyxoma of the vulva. Chromosomal analysis of the tumor demonstrated a sole t(5;8)(p15;q22) translocation. This is the first case of an aggressive angiomyxoma of the vulva with a sole t(5;8)(p15;q22) translocation.

Angiomyxoma diagnosed in a man presenting for abdominal lipectomy

Aggressive angiomyxoma is a rare tumour that is locally infiltrative but nonmetastasizing. It occurs nearly exclusively in adult women of childbearing age and almost always arises in the perineum and pelvic area. A case of angiomyxoma occurring in a middle-aged, morbidly obese man is reported. The clinical presentation was one of progressing scrotal edema and enlargement with subsequent development of scrotal abscesses, requiring several incisions and drainages as well as oral and intravenous antibiotics. His symptoms and body habitus left him in a significantly debilitated state, prompting him to seek treatment for his conditions. He initially presented for abdominal lipectomy. However, due to the chronic scrotal infections and enlargement, scrotectomy was recommended before any other surgical procedures. A scrotectomy was performed by the urology service. Pathological diagnosis of the excised tumour was an aggressive angiomyxoma. Given the rarity of this tumour, especially in males, the proper diagnosis and treatment of angiomyxoma is still being investigated. With this in mind, the physical signs and symptoms that characterize this condition are presented and treatment options are reviewed.

HMGA2 rearrangement in a case of vulvar aggressive angiomyxoma

The histogenesis of aggressive angiomyxoma, an uncommon mesenchymal neoplasm of the vulvar, pelvic, and perineal soft tissues, is poorly understood, although the neoplastic cells exhibit a myofibroblastic phenotype. Cytogenetic studies of aggressive angiomyxoma are scarce; however, a nonrandom involvement of the 12q15 region where the high mobility group (HMG) protein HMGA2, an architectural transcription factor expressed primarily during embryogenesis, is located has been suggested. HMGA2 involvement has also been described in a variety of benign gynecologic mesenchymal neoplasms. We report an additional case of HMGA2 rearrangement in vulvar aggressive angiomyxoma, using fluorescence in situ hybridization.

Aggressive angiomyxoma of male genital region. Report of 4 cases with immunohistochemical evaluation including hormone receptor status

Aggressive angiomyxoma (AA), first described by Steeper and Rosai (Am J SurgPathol. 1983;7:463-475), is a rare locally infiltrative tumor that usually arises in the pelvic and perineal soft tissues of young women. Approximately 150 cases have been reported in women. Aggressive angiomyxoma has a high rate of local recurrence because of its infiltrative growth and anatomical location making complete excision with wide margins difficult. To our knowledge, 39 cases of AA occurring in men have been reported in the literature. Sites frequently involved include the scrotum, spermatic cord, inguinal region, and perineum. The gross and microscopic appearances and clinical course are similar to those described in female cases. Immunohistochemistry evaluating estrogen and progesterone receptors (ER and PR, respectively), although frequently positive in the female cases, has rarely been studied in the male cases. We report the clinicopathologic features of 4 additional cases of AA in men with particular emphasis on hormone (ER/PR) receptor status. Hormone reactivity is significant in that AA may arise from specialized hormonally responsive stromal cells of the perineum and may potentially play a therapeutic role in unresectable tumors. From our small series, hormone positivity (1 case of ER+, 3 cases of PR+) does occur in the male cases of AA, and a large number of cases should be examined to determine the frequency at which these tumors express hormone receptors.

The genetic heterogeneity of uterine leiomyomata

Research investigating the genetics of UL has already been successful in gathering epidemiologic evidence for heritability, establishing the clonal and mosaic nature of these tumors, correlating genotypic and phenotypic characteristics, defining cytogenetic subgroups, and identifying specific genes involved in tumorigenesis. Although UL are known to be benign tumors, the impact they have on the lives of so many women can only be described as "malignant". For this reason, continuing the quest to ascertain the genes, functions, and mechanisms integral to UL development is absolutely imperative. Genetic tests for personalized medical management of women with fibroids is at the threshold for providing the most appropriate treatments (Fig. 3), and combined with developing less invasive therapies portends a brighter future for a major health problem for women.

Deregulation of HMGA2 in an aggressive angiomyxoma with t(11;12)(q23;q15)

Aggressive angiomyxoma is a soft-tissue neoplasm with a predilection for the pelvic and perineal regions and a tendency to recur locally. Cytogenetic data on this tumor type are limited to five cases, three of which showed rearrangement of chromosomal bands 12q13-15. Molecular investigation of two of the tumors identified the HMGA2 gene as the target of the 12q rearrangements. However, the two previously analyzed tumors were different at the molecular level: in one, the rearrangement of 12q13-15 resulted in a fusion product, whereas, in the second case, the breakpoint was telomeric (3') to the HMGA2, leaving the gene intact although expressed in its entire length. To shed more light on the pathobiology of aggressive angiomyxoma and to investigate the molecular mechanisms behind the involvement of the HMGA2 gene in this tumor type (fusion transcript vs deregulated expression), we investigated, cytogenetically and with molecular techniques, one such tumor which presented a t(11;12)(q23;q15) as the sole karyotypic aberration. FISH analyses demonstrated no structural alteration of HMGA2 at the cytogenetic level; however, expression of the full-length gene was detected molecularly.

Aggressive angiomyxoma of the female pelvis and perineum: a case series

Aggressive angiomyxoma (AA) was first described in 1983, and fewer than 150 cases have been reported in the world medical literature. These tumors are benign, locally infiltrative mesenchymal neoplasms with a predilection for the female pelvis and perineum and a tendency to recur. The size of AAs at presentation varies considerably; however, these tumors often achieve large dimensions before becoming clinically symptomatic. Surgical excision remains the mainstay of treatment, but whether clear, tumor-free surgical margins are necessary is controversial. We report a cohort of six patients treated surgically during the past 20 years for primary or recurrent AA. Treatment, surgical margin status, estrogen and progesterone receptor status, and outcomes are reviewed.