Müllerian adenosarcoma with sarcomatous overgrowth and heterologous elements: A case report and literature review.

Uterine mullerian adenosarcoma (MA) is a rare biphasic tumour that accounts for less than 0.5% of uterine neoplasms. The age range of presentation is wide, with the median age in the 5th decade of life. It usually has a good prognosis; however, it worsens when it presents with sarcomatous overgrowth, heterologous elements or infiltrates the myometrium. We report the case of a 63-year-old woman presenting with abnormal vaginal bleeding and a sensation of solid material coming out of the cervical canal who was diagnosed with mullerian adenosarcoma with sarcomatous overgrowth (MASO) and presence of heterologous elements after performing a mass biopsy and subsequent hysterectomy. We reviewed the literature, focusing especially on the differential diagnoses to be evaluated, as well as the differences in prognosis and treatment according to whether or not they present histologic features of poor prognosis.

Clinicopathological characteristics and prognosis of uterine sarcoma: a 10-year retrospective single-center study in China.

BACKGROUND: Uterine sarcoma is a rare and heterogeneous gynecological malignancy characterized by aggressive progression and poor prognosis. The current study aimed to investigate the relationship between clinicopathological characteristics and the prognosis of uterine sarcoma in Chinese patients. METHODS: In this single-center retrospective study, we reviewed the medical records of 75 patients with histologically verified uterine sarcoma treated at the First Affiliated Hospital of Xi'an Jiaotong University between 2011 and 2020. Information on clinical characteristics, treatments, pathology and survival was collected. Progression-free survival (PFS) and overall survival (OS) were visualized in Kaplan-Meier curves. Prognostic factors were identified using the log-rank test for univariate analysis and Cox-proportional hazards regression models for multivariate analysis. RESULTS: The histopathological types included 36 endometrial stromal sarcomas (ESS,48%), 33 leiomyosarcomas (LMS,44%) and 6 adenosarcomas (8%). The mean age at diagnosis was 50.2 ± 10.7 years. Stage I and low-grade accounted for the majority. There were 26 recurrences and 25 deaths at the last follow-up. The mean PFS and OS were 89.41 (95% CI: 76.07-102.75) and 94.03 (95% CI: 81.67-106.38) months, respectively. Univariate analysis showed that > 50 years, post-menopause, advanced stage, ≥ 1/2 myometrial invasion, lymphovascular space invasion and high grade were associated with shorter survival (P < 0.05). Color Doppler flow imaging positive signals were associated with shorter PFS in the LMS group (P = 0.046). The ESS group had longer PFS than that of the LMS group (99.56 vs. 76.05 months, P = 0.043). The multivariate analysis showed that post-menopause and advanced stage were independent risk factors of both PFS and OS in the total cohort and LMS group. In the ESS group, diagnosis age > 50 years and high-grade were independent risk factors of PFS, while high-grade and lymphovascular space invasion were independent risk factors of OS. CONCLUSION: In Chinese patients with uterine sarcoma, post-menopause and advanced stage were associated with a significantly poorer prognosis. The prognosis of ESS was better than that of LMS. Color Doppler flow imaging positive signals of the tumor helped to identify LMS, which needs to be further tested in a larger sample in the future.

Mullerian adenosarcoma of the uterus with MASO: a case report of cervical adenosarcoma in a young female that never had sexual behavior.

BACKGROUND: Cervical mullerian adenosarcoma is a rare uterine sarcoma, especially in young women. Its pathological features are low-grade malignant tumors with bidirectional differentiation, and the degree of malignancy is similar to that of low-grade endometrial stromal sarcoma. This paper reports the case of a young asexual patient who has been closely followed up after tumor resection and has not had any recurrences. CASE PRESENTATION: A 20-year-old, young asexual woman was diagnosed with cervical mullerian adenosarcoma with sarcomatous overgrowth (MASO). Cervical tumor resection was performed after admission, and the resection margin was negative. After the operation, she refused to undergo secondary surgery due to fertility requirements and did not receive adjuvant treatment. The patient was closely followed up after the operation and has not yet relapsed. CONCLUSION: A young woman with cervical MASO did not receive adjuvant treatment after cervical tumor resection. For women with fertility requirements, close follow-ups should be conducted after the operation to guard against tumor recurrence and radical tumor resection should be performed as early as possible after the patient no longer requires their fertility.

Uterine adenosarcoma: Clinical significance of histological classification and SNP array analysis.

Mullerian adenosarcoma is a rare malignant biphasic tumor. The mesenchymal component may be low or high grade, with or without sarcomatous overgrowth (SO). Little is known about the molecular heterogeneity of these tumors. In this study, we aim to reclassify a large retrospective monocentric cohort of uterine adenosarcomas according to tumor grade and SO, to evaluate the clinical significance of pathological classification and to correlate with copy-number variations inferred from single nucleotide polymorphism array. Of the 67 uterine adenosarcomas, 18 (26.9%) were low grade without SO, 7 (10.4%) low grade with SO, 8 (11.9%) high grade without SO and 34 (50.7%) high grade with SO. SO, necrosis and RMS were more frequent in high grade than low grade adenosarcomas (p < 0.001). Low-rank test showed that recurrence-free survival was significantly shortened in high grade than low grade adenosarcomas (p = 0.035) and SO was associated with shortened overall and recurrence-free survival (p = 0.038 and p = 0.009, respectively). High-grade tumors displayed complex genomic profiles with multiple segmental losses including TP53, ATM and PTEN genes. The median genomic index was significantly higher in high grade than low grade tumors (27 [3-60] vs 5,3 [0-16], p < 0.0001) and was significantly higher in presence of SO in low grade tumors (12,8 [10-16] vs 2,6 [0-10], p = 0.0006). We propose to report sarcomatous overgrowth with the tumor grade for prognostication in adenosarcoma and representative sampling is crucial for evaluation of these histological criteria.

Clinicopathological analysis of 22 Müllerian adenosarcomas and the sequencing of DICER1 mutation.

BACKGROUND: Müllerian adenosarcoma, a rare malignancy, presents diagnostic and therapeutic challenges. In this study, we conducted an analysis of the clinicopathological characteristics of 22 adenosarcomas, with a particular focus on screening for DICER1 hot mutations. METHODS: The cohort consisted of patients with adenosarcoma who were registered at the West China Second Hospital between the years 2020 and June 2022. Sanger sequencing was employed to screen for somatic Hotspot mutations in the RNase IIIb domain of DICER1 in the 22 adenosarcomas. RESULTS: Only one patient exhibited a DICER1 mutation that was not a DICER1 Hotspot mutation. Among the 22 patients, all underwent total hysterectomy with bilateral salpingo-oophorectomy, and 14 out of these 22 patients received adjuvant treatment. CONCLUSION: In summary, our study of 22 Müllerian adenosarcomas focused on the clinicopathological features and the presence of DICER1 Hotspot mutations. Although our findings did not reveal any DICER1 mutations in the studied samples, this negative result provides valuable information for the field by narrowing down the genetic landscape of adenosarcomas and highlighting the need for further research into alternative molecular pathways driving this malignancy.

SMARCA4 / BRG1 -deficient Uterine Neoplasm With Hybrid Adenosarcoma and Carcinoma Features: Expanding the Molecular-morphologic Spectrum of SMARCA4 -driven Gynecologic Malignancies.

SMARCA4 gene encodes BRG1 , a member of the SWItch/sucrose non-fermentable protein family involved in epigenetic transcriptional regulation of important cellular processes. In the uterine corpus, SMARCA4 / BRG1 deficiency is associated with a novel class of undifferentiated uterine sarcomas, characterized by younger age onset, rhabdoid histology, focal phyllodiform architecture, high-risk pathologic findings, and dismal prognosis. Herein, we report a case of a 34-year-old Asian woman with a SMARCA4 / BRG1 -deficient uterine tumor fulfilling the clinicopathologic features of an undifferentiated uterine sarcoma. However, the tumor exhibited several unique features that have not been previously emphasized, including (1) conspicuous phyllodiform architecture recapitulating conventional adenosarcoma, (2) rhabdoid tumor cells forming cords and keratin-positive cohesive epithelial islands, and (3) cooccurrence with a spatially distinct and discrete endometrial complex atypical hyperplasia from the rest of the proliferation. By immunohistochemistry, the tumor cells were diffusely positive for synaptophysin, whereas BRG1 was lost. Pertinent molecular findings included frameshift mutations in the SMARCA4 gene, mutations in histone modification and chromatin remodeling genes, including KMT2C , ARID1B , KAT6A , and NCOR1 , and mutations in Wnt signaling involving APC and CTNNB1 . Copy number gain in MDM2 and CDK4 were also identified. The tumor mutation burden was intermediate (6.8/MB) and it was microsatellite stable. On balance, our case exhibited morphologic and molecular features that overlap with (1) an undifferentiated uterine sarcoma, (2) an adenosarcoma with sarcomatous overgrowth, and (3) a mixed adenosarcoma and undifferentiated endometrial carcinoma. These hybrid features further expand the molecular-morphologic spectrum of SMARCA4 / BRG1 -deficient uterine neoplasms.

Prognostic factors in patients with uterine sarcoma: the SARCUT study.

OBJECTIVE: Uterine sarcomas are a rare and heterogeneous group of malignancies that include different histological sub-types. The aim of this study was to identify and evaluate the impact of the different prognostic factors on overall survival and disease-free survival of patients with uterine sarcoma. METHODS: This international multicenter retrospective study included 683 patients diagnosed with uterine sarcoma at 46 different institutions between January 2001 and December 2007. RESULTS: The 5-year overall survival for leiomyosarcoma, endometrial stromal sarcoma, undifferentiated sarcoma, and adenosarcoma was 65.3%, 78.3%, 52.4%, and 89.5%, respectively, and the 5-year disease-free survival was 54.3%, 68.1%, 40.3%, and 85.3%, respectively. The 10-year overall survival for leiomyosarcoma, endometrial stromal sarcoma, undifferentiated sarcoma and adenosarcoma was 52.6%, 64.8%, 52.4%, and 79.5%, respectively, and the 10-year disease-free survival was 44.7%, 53.3%, 40.3%, and 77.5%, respectively. The most significant factor associated with overall survival in all types of sarcoma except for adenosarcoma was the presence of residual disease after primary treatment. In adenosarcoma, disease stage at diagnosis was the most important factor (hazard ratio 17.7; 95% CI 2.86 to 109.93). CONCLUSION: Incomplete cytoreduction, tumor persistence, advanced stage, extra-uterine and tumor margin involvement, and the presence of necrosis were relevant prognostic factors significantly affecting overall survival in uterine sarcoma. The presence of lymph vascular space involvement and administration of adjuvant chemotherapy were significantly associated with a higher risk of relapse.

Differential diagnosis of uterine adenosarcoma: identification of JAZF1-BCORL1 rearrangement by comprehensive cancer genomic profiling.

BACKGROUND: Uterine adenosarcoma is a rare malignant tumor that accounts for 8% of all uterine sarcomas, and less than 0.2% of all uterine malignancies. However, it is frequently misdiagnosed in clinical examinations, including pathological diagnosis, and imaging studies owing to its rare and non-specific nature, which is further compounded by the lack of specific diagnostic markers. CASE PRESENTATION: We report a case of uterine adenosarcoma for which a comprehensive genomic profiling (CGP) test provided a chance to reach the proper diagnosis. The patient, a woman in her 60s with a history of uterine leiomyoma was diagnosed with an intra-abdominal mass post presentation with abdominal distention and loss of appetite. She was suspected to have gastrointestinal stromal tumor (GIST); the laparotomically excised mass was found to comprise uniform spindle-shaped cells that grew in bundles with a herringbone architecture, and occasional myxomatous stroma. Immunostaining revealed no specific findings, and the tumor was diagnosed as a spindle cell tumor/suspicious adult fibrosarcoma. The tumor relapsed during postoperative follow-up, and showed size reduction with chemotherapy, prior to regrowth. CGP was performed to identify a possible treatment, which resulted in detection of a JAZF1-BCORL1 rearrangement. Since the rearrangement has been reported in uterine sarcomas, we reevaluated specimens of the preceding uterine leiomyoma, which revealed the presence of adenosarcoma components in the corpus uteri. Furthermore, both the uterine adenosarcoma and intra-abdominal mass were partially positive for CD10 and BCOR staining. CONCLUSION: These results led to the conclusive identification of the abdominal tumor as a metastasis of the uterine adenosarcoma. The JAZF1-BCORL1 rearrangement is predominantly associated with uterine stromal sarcomas; thus far, ours is the second report of the same in an adenosarcoma. Adenosarcomas are rare and difficult to diagnose, especially in atypical cases with scarce glandular epithelial components. Identification of rearrangements involving BCOR or BCORL1, will encourage BCOR staining analysis, thereby potentially resulting in better diagnostic outcomes. Given that platinum-based chemotherapy was proposed as the treatment choice for this patient post diagnosis with adenosarcoma, CGP also indirectly contributed to the designing of the best-suited treatment protocol.

Malignant Mixed Mullerian Tumor Arising from Endometriosis in the Groin: A Case Report and Literature Review.

This was a 57-year-old woman who presented with mild discomfort in the right groin. Physical examination revealed a mass in the right groin, and by ultrasound, the mass was hypoechoic and solid with some internal vascularity. The clinical differential diagnosis included lymphoma and others. The mass was excised for pathologic evaluation. Gross examination of the specimen revealed a 3 × 2.4 × 2 cm, solid and cystic mass. Microscopically, it was a biphasic tumor consisting of carcinomatous and sarcomatous components. The tumor was seen contiguous with endometriosis and atypical endometrioid hyperplasia. The histologic findings were consistent with malignant mixed Mullerian tumor (MMMT) arising from endometriosis in the right groin. The tumor involved the resection margin. Subsequent chest/abdominal/pelvic computed tomography did not reveal evidence of tumors, and diagnostic peritoneal/pelvic laparoscopy did not show diseases. Postoperatively, the patient received 6 cycles of chemotherapy consisting of carboplatin and paclitaxel, followed by radiation in the right groin. Malignant transformation from endometriosis occurs in less than 1% of endometriosis cases, and about 80% of the transformed tumors occur in the ovaries. The most commonly transformed malignant tumors are endometrioid and clear cell carcinomas, with rare adenosarcoma and endometrial stromal sarcoma reported. To our knowledge, we are reporting the first case of MMMT arising from endometriosis in the groin.

Epidemiology of adenosarcoma and the inverse probability of treatment weighting (IPTW) adjusted survival analysis of lymph node dissection in uterine adenosarcoma.

The objective for the study was to analysis the epidemiology of adenosarcoma, and independent prognostic factors and impact of lymph node dissection (LND) of uterine adenosarcoma. Cases of patients with primary adenosarcoma were obtained from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2016. Overall survival was analyzed by the Kaplan-Meier method and log-rank test. The differences in baseline covariates between the 2 groups were adjusted by inverse probability of treatment weighting method. The prognostic factors were identified by univariate and multivariate Cox regression analysis and hazard ratio and 95% confidence interval (CI) of covariates were also estimated. 1129 patients with pathological primary adenosarcoma between 2000 and 2016 were identified from the surveillance, epidemiology, and end results database. The only 4 patients were male. 1027 patients with primary uterine adenosarcoma, and 53.1% underwent LND and only 3.5% patients were with positive lymph node. Age, marital status, largest tumor size, tumor grade, T stage and chemotherapy were significantly correlated with survival. Race, tumor number, LND, and radiotherapy did not affect overall survival in patients. Inverse probability of treatment weighting-adjusted K-M curve showed that LND did not improve survival and lymph node metastasis (LNM) did not affect survival. The majority of primary adenosarcoma patients are female with high incidence of uterus and rare incidence of distant metastasis. Age, marital status, tumor size, T stage, grade, and chemotherapy are independent prognostic factors of uterine adenosarcoma. LNM was not a significant prognostic risk factor, and LND did not benefit survival.

Mullerian adenosarcoma: clinicopathologic and molecular characterization highlighting recurrent BAP1 loss and distinctive features of high-grade tumors.

Mullerian adenosarcoma is an uncommon mesenchymal tumor of the gynecologic tract. Most cases are low-grade, while high-grade adenosarcomas are rare and not well studied. Herein, we characterize the clinicopathologic and molecular features of 27 adenosarcomas of gynecologic origin, enriched for high-grade tumors subjected to targeted panel sequencing. Sarcomatous overgrowth was more frequently seen in high-grade compared to low-grade tumors (12/17, 71%, vs 1/10, 10%, p = 0.004) and heterologous elements were exclusive to high-grade cases (n = 7, p = 0.03). All deaths were from high-grade disease (advanced primary, n = 2, or recurrence, n = 5). Genetic alterations specific to high-grade adenosarcomas have known associations with chromosome instability, including TP53 mutations (n = 4) and amplifications of MDM2 (n = 2) and CCNE1 (n = 2). Somatic ATRX frameshift mutations were found in 2 patients with high-grade recurrences following a primary low-grade adenosarcoma and ATRX deletion in 1 high-grade adenosarcoma with an adjacent low-grade component. The fraction of genome altered by copy number alterations was significantly higher in high-grade compared to low-grade adenosarcomas (P = 0.001). Other recurrent genetic alterations across the entire cohort included BAP1 homozygous deletions (n = 4), DICER1 mutations (n = 4), ARID1A mutations (n = 3), TERT promoter mutations (n = 2) and amplification (n = 1), as well as alterations involving members of the PI3K and MAPK signaling pathways. One tumor harbored an ESR1-NCOA3 fusion and another had an MLH1 homozygous deletion. Immunohistochemical analysis for BAP1 revealed loss of nuclear expression in 6/24 (25%) cases, including all four tumors with BAP1 deletions. Notably, out of 196 mesenchymal neoplasms of gynecologic origin, BAP1 homozygous deletion was only found in adenosarcomas (P = 0.0003). This study demonstrates that high-grade adenosarcomas are heterogeneous at the molecular level and are characterized by genomic instability and TP53 mutations; ATRX loss may be involved in high-grade transformation of low-grade adenosarcoma; and BAP1 inactivation appears to be a specific pathogenic driver in a subset of adenosarcomas.

Uterine Adenosarcoma in a Teen Ager.

Uterine adenosarcoma is a rare tumor composed of benign epithelium in combination with malignant mesenchymal components. Misdiagnosis is common due to the lack of specific clinical manifestations and the rarity of such tumors in young age groups. The mean age at diagnosis is 58.6 years, and <10% of patients are younger than 40 years. Herein, we describe a case of a 19-year girl who presented with worsening menorrhagia. Her ultrasound revealed multiple heterogeneous masses in the uterine cavity. Intraoperatively, a small piece of grayish-white tumor tissue was sent for the frozen section, but the results did not confirm malignancy. She underwent hysteroscopy, laparoscopic hysterectomy, and bilateral salpingo-oophorectomy. Histopathologic examination finally confirmed uterine adenosarcoma. The patient had no evidence of residual tumor or recurrence during six months of follow-up. Key Words: Uterus, Adenosarcoma, Mixed tumor.

Atypical uterine polyps show morphologic and molecular overlap with mullerian adenosarcoma but follow a benign clinical course.

A subset of clinically benign uterine polyps shows atypical morphologic features worrisome for, but not diagnostic of, Mullerian adenosarcoma. We report clinicopathologic data for 63 polyps from 58 women with atypical morphologic features including abnormal architecture, abnormal periglandular stroma, stromal atypia, and mitoses >2 per 10 hpf. Four (11%) of 36 women with follow-up tissue sampling had residual/recurrent atypical polyp. Twelve (27%) of 44 women underwent hysterectomy subsequent to a diagnosis of atypical polyp. No patient developed adenosarcoma over median follow-up of 150 months. Twenty-one primary atypical polyps underwent molecular profiling. Five (24%) harbored chr 12q13-15 gain or amplification, 9/20 (45%) harbored chr 6q25.1 gain, and 7/21 (33%) had no significant copy number alterations. Gains of chr 1q, chr 8p12, and chr 10q11.21-23, amplifications of chr 12q24.12-13, chr 15p24.1-26.1, and chr 18q21.33, and loss of chr 7 and chr 11q21 were each seen in a single polyp. Mean tumor mutational burden was 3.1 (range, 0.76-8.365) mutations/Mb. Pathogenic point mutations were identified in 12/20 (60%) primary atypical polyps. We propose the term "atypical uterine polyps" for these lesions, which show biologic overlap with early Mullerian adenosarcoma but lack molecular alterations characteristic of clinically aggressive adenosarcoma and appear to follow a benign clinical course. Conservative management with close clinical follow-up and repeat sampling can be considered for these lesions, when clinically appropriate.

Imaging findings of uterine adenosarcoma with sarcomatous overgrowth: two case reports, emphasizing restricted diffusion on diffusion weighted imaging.

BACKGROUND: Adenosarcoma is classified as a mixed epithelial and mesenchymal tumor composed of a benign epithelial component and a malignant stromal component. The stromal component in adenosarcoma is usually low grade, and consequently the prognosis is relatively favorable. While, adenosarcoma with sarcomatous overgrowth (SO) is defined as an adenosarcoma in which the sarcomatous component constitutes more than 25% of the tumor. The stromal component is also high-grade sarcoma showing greater nuclear pleomorphism and mitotic activity, thus, it is associated with worse prognosis. MRI findings of adenosarcoma without SO have been described in previous literatures but the imaging findings in adenosarcoma with SO may be poorly defined. Therefore we present two cases of uterine adenosarcoma with SO. CASE PRESENTATION: Patient 1 was a 76-year-old woman referred to our hospital with complaint of abdominal distension and postmenopausal bleeding. Patient 2 was a 57-year-old woman with complaint of lower abdominal pain and abnormal uterine bleeding. On magnetic resonance imaging (MRI), T2 weighted imaging showed a large, heterogeneous high-intensity mass with hyperintense tiny cysts that expanded the uterine cavity and extended into the cervical canal for both patients. On diffusion-weighted imaging (DWI), both masses appeared as high signal intensity. Patient 2 also had a right ovarian adult granulosa cell tumor that may have contributed to development of the adenosarcoma. Patient 1 recurred with peritoneal sarcomatosis 6 months after surgery and died of the disease. Patient 2 also recurred with a left upper lung metastasis 3 months after surgery. CONCLUSIONS: DWI may depict pathological changes produced by SO of adenosarcoma as high signal intensity, even though SO does not seem to change MRI findings of adenosarcoma on other sequences. Therefore, DWI could potentially predict SO in presumptive adenosarcoma on MRI and the patient's prognosis. It is also important for pathologists to know if SO can arise in adenosarcoma because they need to examine the tumor thoroughly to determine the percentage of SO component in the tumor volume when SO is present.

SATB2 Expression in Uterine Sarcoma: A Multicenter Retrospective Study.

Uterine sarcomas represent a clinical challenge because of their difficult diagnosis and the poor prognosis of certain subtypes. The aim of this study was to evaluate the expression of the special AT-rich sequence-binding protein 2 (SATB2) in endometrial stromal sarcoma (ESS) and other types of uterine sarcoma by immunohistochemistry. We studied the expression of SATB2 on 71 full tissue sections of endometrial stromal nodule, low-grade ESS, uterine leiomyomas and leiomyosarcoma, undifferentiated uterine sarcoma, adenosarcoma, and carcinosarcoma samples. Nuclear SATB2 expression was then evaluated in an extended sample set using a tissue microarray, including 78 additional uterine tumor samples. Overall, with a cut-off of ≥10% of tumor cell staining as positive, the nuclear SATB2 score was negative in all endometrial stromal nodule samples (n=10) and positive in 83% of low-grade ESS samples (n=29/35), 40% of undifferentiated uterine sarcoma (n=4/10), 13% of leiomyosarcoma (n=2/16), 14% of adenosarcoma (n=3/22), and 8% carcinosarcoma (n=2/25) samples. Furthermore, in ESS patients, direct comparison of nuclear SATB2 scores with clinicopathologic parameters and other reported biomarkers such as progesterone receptor and estrogen receptor showed that nuclear SATB2 was associated with PR expression and a decreased risk of disease-specific death (odds ratio=0.06, 95% confidence interval=0.04-0.81, P=0.04). Our data suggest that SATB2 could be a marker with relative sensitivity (83%) for distinguishing between endometrial stromal nodule and ESS with potential prognostic value.

Mixed Endometrioid Adenocarcinoma and Müllerian Adenosarcoma of the Uterus and Ovary: Clinicopathologic Characterization With Emphasis on its Distinction From Carcinosarcoma.

Mullerian adenosarcoma is a biphasic neoplasm composed of benign or atypical Müllerian epithelium and a malignant mesenchymal component that is usually, but not always, of low grade. Focal architectural or cytologic atypia of the epithelial component resembling atypical hyperplasia may uncommonly be present and foci of adenocarcinoma have been rarely reported. Whether the coexistence of these 2 tumor components is a result of independent primaries (collision tumor), adenocarcinoma arising from the epithelial component of the adenosarcoma, an unusual form of carcinosarcoma or some other mechanism is uncertain. To establish the diagnostic criteria and clinical significance of the coexistence of adenocarcinoma in close association with Müllerian adenosarcoma, we conducted a multi-institutional study of these rare tumors. Twenty-six patients were identified with "mixed" adenosarcoma and adenocarcinoma; they ranged in age from 43 to 87 years (median: 66 y). Tumors occurred in the uterine corpus (n=22), ovary (n=2), and the pelvis (n=2). All but 6 had International Federation of Gynecology and Obstetrics (FIGO) stage I disease. All extrauterine tumors were associated with endometriosis. The tumor size ranged from 2 to 25 cm (median: 7.9 cm). The sarcomatous component was of low grade in 18 and high grade in 8 (the majority demonstrating rhabdomyoblastic differentiation); 9 had stromal overgrowth. Twenty-five carcinomas were endometrioid in type (23 FIGO grade 1; 3 FIGO grade 2) and 1 carcinoma was dedifferentiated with FIGO grade 1 endometrioid adenocarcinoma component; 33% of the uterine neoplasms were associated with adjacent endometrial hyperplasia. Next-generation sequencing in 2 tumors identified similar molecular abnormalities in the sarcomatous and carcinomatous components supporting a clonal relationship. Of 10 patients with available follow-up (median: 18 mo), 8 had no evidence of disease and 2 died of recurrent sarcoma at 7 and 8 months. Endometrioid adenocarcinomas that arise in close spatial association with Müllerian adenosarcoma appear to be clonally related to the sarcoma. Unlike carcinosarcomas, these tumors are usually early stage at presentation. The prognosis appears to be driven by the sarcomatous component. These tumors should be distinguished from carcinosarcomas, dedifferentiated endometrial carcinomas, and corded and hyalinized endometrioid carcinomas.

PAX8-positive, Cytokeratin-positive Intra-abdominal Ewing Sarcoma Masquerading as a Mullerian Carcinoma in a Postmenopausal Female.

Extraskeletal Ewing sarcoma presenting as intra-abdominal or pelvic disease in adult female patients is very rare and may lead to diagnostic difficulty due to clinical and histologic overlap with Mullerian adenocarcinomas, which are far more common. We report a case of an intra-abdominal Ewing sarcoma in a postmenopausal female patient whose clinical and radiological presentation closely resembled that of peritoneal carcinomatosis. Biopsy of an omental nodule revealed numerous histologic features suggestive of a Mullerian carcinoma, including gland-like rosettes, strong, diffuse PAX8 immunoreactivity and cytokeratin expression. After excluding other differential diagnostic considerations, the possibility that this might represent an intra-abdominal Ewing sarcoma was entertained. Reverse transcriptase polymerase chain reaction testing demonstrated the presence of an EWSR1-ERG fusion transcript, confirming the diagnosis. The differential diagnostic considerations when dealing with this unusual clinical scenario and the uncommon yet important pitfall of PAX8 immunoreactivity in Ewing sarcoma are discussed.

Uterine Adenosarcoma Originating in Adenomyosis: Report of an Extremely Rare Phenomenon and Review of Published Literature.

Müllerian adenosarcoma is an uncommon biphasic malignant tumor most often occurring in the uterine corpus and derived from native surface endometrium. We report a case of intramural uterine adenosarcoma arising in association with adenomyosis, in the absence of tumor involving the surface endometrium. This is an extremely rare phenomenon, with only 8 other published cases of uterine corpus adenosarcoma in the absence of surface endometrial involvement, 5 originating in adenomyosis and 3 in adenomyomas. We review these cases. The current FIGO staging system for uterine adenosarcoma assumes origin from the surface endometrium and does not address the rare occurrence of intramural tumors without a surface endometrial component. Such tumors are problematic to stage and could potentially be overtreated, particularly if there is deep myometrial involvement.

DICER1-associated embryonal rhabdomyosarcoma and adenosarcoma of the gynecologic tract: Pathology, molecular genetics, and indications for molecular testing.

Gynecologic sarcomas are uncommon neoplasms, the majority occurring in the uterus. Due to the diverse nature of these, the description of "new" morphological types and the rarity of some of them, pathological diagnosis and treatment is often challenging. Finding genetic alterations specific to, and frequently occurring, in a certain type can aid in the diagnosis. DICER1 is a highly conserved ribonuclease crucial in the biogenesis of microRNAs and mutations in DICER1 (either somatic or germline) have been detected in a wide range of sarcomas including genitourinary embryonal rhabdomyosarcomas (ERMS) and adenosarcomas. Importantly, DICER1-associated sarcomas share morphological features irrespective of the site of origin such that the pathologist can strongly suspect a DICER1 association. A review of the literature shows that almost all gynecologic ERMS reported (outside of the vagina) harbor DICER1 alterations, while approximately 20% of adenosarcomas also do so. These two tumor types exhibit significant morphological overlap and DICER1 tumor testing may be helpful in distinguishing between them, because a negative result makes ERMS unlikely. Given that germline pathogenic DICER1 variants are frequent in uterine (corpus and cervix) ERMS and pathogenic germline variants in this gene cause a hereditary cancer predisposition syndrome (DICER1 syndrome), patients diagnosed with these neoplasms should be referred to medical genetic services. Cooperation between pathologists and geneticists is crucial and will help in improving the diagnosis and management of these uncommon sarcomas.

Immunohistochemical markers and the clinical course of adenosarcoma: a series of seven cases.

BACKGROUND: Uterine adenosarcoma, a rare uterine tumor subtype, is a biphasic tumor consisting of epithelial and mesenchymal elements. To date, there is no research comparing the histopathological features and immunohistochemistry of primary and recurrent tumors; furthermore, the relationship between pathology and the clinical course remains unclear. We reviewed the pathology and immunohistochemical features of patients with adenosarcoma and investigated the relevance of the histomorphological features to the clinical course. We also compared the immunohistochemical features of the primary and recurrent tumors. METHODS: The data of seven patients with adenosarcoma who underwent surgery in our hospital were evaluated. We performed immunohistochemical staining for the progesterone receptor, estrogen receptor, p53, and two Switch/Sucrose Non-Fermentable chromatin remodeling proteins (SMARCA4, BCOR), which were recently developed for the undifferentiated sarcoma diagnosis in addition to conventional staining methods. RESULTS: All patients had International Federation of Gynecology and Obstetrics stage IB-IC diseases. All tumors were polypoid and every patient presented with abnormal uterine bleeding. Six patients aged over 50 years and were menopausal; one patient aged under 50 years and was non-menopausal (average age: 59.1 years). Histologically, the sarcomatous components were homologous and heterogenous in six and one patient, respectively. Four and three cases were recurrent and non-recurrent, respectively. The recurrent patients showed high-grade morphology with sarcomatous overgrowth and were negative for ER and PR. Three recurrences could be evaluated by imaging, showing recurrence only in a distant area; biopsy specimens from these tissues revealed the identical mesenchymal component found in the primary tumor without a benign epithelial component. Immunohistochemical staining results were also similar to the corresponding of the original tumor, except for the p53 expression in one patient. At the primary site, p53 was overexpressed in two recurrent patients and had a wild-type level in one recurrent patient; however, all three recurrent tissues showed p53 overexpression. None of our patients showed SMARCA4 loss, and BCOR expression was positive in one case. CONCLUSIONS: Initial pathological adenosarcoma analysis with appropriate immunohistochemical staining is vital for prognostic assessment. p53 expression might increase at recurrence. SMARCA4 and BCOR might not be an index of malignancy.