Uterine tumors with neuroectodermal differentiation: a series of 17 cases and review of the literature. Am J Surg Pathol. 2008;32:219-228. [PMID: 18223324 DOI: 10.1097/pas.0b013e318093e421]

Clinicopathologic and molecular characterization of primitive neuroectodermal tumors (PNET) in the female genital tract: a retrospective study of 8 cases

AIMS

This study aimed to investigate the molecular alterations in primitive neuroectodermal tumors (PNET) of the female genital tract.

METHODS

We retrospectively analyzed the clinicopathologic and immunohistochemical features of 8 gynecologic PNET cases (3 cervical, 1 vaginal, and 4 ovarian). Fluorescence in situ hybridization and targeted next-generation sequencing (NGS) were performed to identify molecular alterations in these tumors.

RESULTS

The cohort included 5 FIGO stage I, 1 stage III, and 2 stage IV tumors. Two patients with stage IV disease died at 8 and 12 months. The cervical/vaginal tumors consisted of small round blue cells arranged in sheets, with EWSR1 rearrangements and concurrent diffuse expression of membranous CD99 and nuclear FLI1. The ovarian tumors displayed diverse morphologic features resembling central nervous system (CNS) tumors, including embryonal tumor with multilayered rosettes (case 5), medulloblastoma (case 6), glioblastoma (case 7), and ependymoma (case 8). Three ovarian tumors were associated with teratomas. None of the ovarian tumors exhibited EWSR1 rearrangements or i(12p)/12p overrepresentation. NGS identified an EWSR1::exon11∼FLI1::exon6 fusion in one cervical PNET, with no additional molecular alterations. In contrast, three ovarian tumors lacked common genetic changes seen in CNS tumors but harbored several significant variants, including NTRK2 exon11 c.1019C > T (p.T340 M) (case 6), INPP4B exon23 c.2221G > A (p.V741 M) (case 7), and FANCG exon7 c.882_883insA (p.D295Rfs∗14) with MET 7q31 polysomy (case 8).

CONCLUSIONS

Our findings confirm that cervical/vaginal and ovarian PNET represent two distinct tumor types. Ovarian PNET have different pathogenetic pathways from their CNS and testicular counterparts most likely.

The Spectrum of Fusions Occurring in Non-Smooth Muscle Mesenchymal Uterine Tumors: A Review of the Current Knowledge

CONTEXT.—

Non-smooth muscle uterine sarcomas are mostly represented by low-grade endometrial stromal sarcoma. However, several other rare, distinct types of uterine sarcoma are recognized, including high-grade endometrial stromal sarcoma, tumors with kinase fusions, uterine tumors resembling ovarian sex cord tumors, soft tissue-type sarcoma, and emerging entities such as KAT6A/B-rearranged tumors. The landscape of uterine sarcomas has changed, mostly because of the increasing knowledge concerning their molecular aberrations.

OBJECTIVE.—

To offer a comprehensive review of the literature focusing on fusions occurring in tumors other than smooth muscle mesenchymal uterine tumors with respect to their type, frequency, and overlap between diagnostic categories and entities.

DATA SOURCES.—

The data were mined from the PubMed/MEDLINE database covering the time period from January 1988 to June 2023. In total, 156 studies focusing on the problematics of fusions occurring in non-smooth muscle mesenchymal uterine tumors were selected, and thus became the basis for this review.

CONCLUSIONS.—

One hundred ten fusions were identified in 703 tumors. The diagnostic significance of the molecular aberrations occurring in these tumors can be unclear in some cases. This can be related to the rare aberrations with a limited number of reported cases. Additionally, even well-known aberrations considered as specific for a certain distinct entity can occur in other lesions, the biological behavior and clinical significance of which can differ substantially.

Uterine carcinosarcoma showing immature teratoid-like differentiation

A carcinosarcoma is a rare form of cancer characterised by the presence of both carcinomatous and sarcomatous components. Here, we present our experience with an extremely rare case of an uterine carcinosarcoma with immature teratoid-like differentiation. The patient was a woman in her 60s. She was referred for the evaluation of a uterine tumour. She underwent total abdominal hysterectomy with bilateral adnexectomy and received postoperative treatment with paclitaxel and carboplatin. On microscopic examination, the tumour had a heterogeneous appearance with a combination of carcinomatous and sarcomatous elements, and teratoid features. The tumour included immature squamous epithelial cells and immature epithelial glands, and focal atypical fused glands, which are consistent with endometrioid carcinoma, were identified in the endometrium. Pathological differentiation from extrarenal Wilms' tumour and teratocarcinosarcoma was challenging. The final pathological diagnosis was uterine carcinosarcoma with immature teratoid-like differentiation. At 14 months after the surgery, the patient has not experienced recurrence.

Uterine Tumors Resembling Ovarian Sex Cord Tumors: A Clinicopathologic Study of 75 Cases Emphasizing Features Predicting Adverse Outcome and Differential Diagnosis

Uterine tumors resembling ovarian sex cord tumors (UTROSCTs), first characterized by Drs Clement and Scully in 1976, are rare neoplasms showing clinical, morphologic, and immunohistochemical overlap with a number of other uterine tumors, most being mesenchymal. Criteria for aggressive behavior are not clearly established. We report 75 tumors from patients ranging from 21 to 84 (mean=52.4) years. Seventy-one patients were treated by hysterectomy and 4 by conservative total excision. Thirty-eight tumors were intramyometrial, 34 submucosal, and 3 cervical; they ranged from 0.6 to 20 (mean=4.9) cm and were typically tan-yellow. Sixty-eight neoplasms were well-circumscribed and 7 had infiltrative borders (4 only minimally). In 56 tumors, a smooth muscle component was intimately admixed with the neoplastic cells ("pseudoinfiltration"; extensive in 29). Architectural patterns included cords (n=53), diffuse (n=51), hollow tubules (n=48), nests (n=38), trabeculae (n=37), retiform (n=23), solid tubules (n=21), pseudoangiomatoid (n=11), pseudopapillary (n=4), and whorled (n=2); typically, more than 1 pattern was seen. Tumor cells were epithelioid (n=62), epithelioid and spindled (n=12), or spindled (n=1) and/or rhabdoid (n=20; extensive in 2). Cytologic atypia was absent to mild in 57, moderate in 16, and moderate to severe in 2 tumors. Fifty-seven UTROSCTs had ≤2mitoses/10 high power fields (HPF), 12 had 3 to 5/10 HPF, and 6 >5/10 HPF. Necrosis was present in 3 and lymphovascular invasion in 1. Tumor cells showed a polyphenotypic immunohistochemical profile (with positivity for sex cord, smooth muscle, and epithelial markers), most commonly inhibin (17/33+) and calretinin (22/31+) positive. Five of 58 patients with follow-up (22 to 192; mean=73.2 mo) had recurrences/metastases from 30 to 144 months, and 2 died of disease. Malignant tumors showed >3 of the following 5 features compared with benign tumors: size >5 cm, at least moderate cytologic atypia, ≥3 mitoses/10 HPF, infiltrative borders, and necrosis. One of the 5 malignant tumors showed an extensive rhabdoid morphology. UTROSCTs are uncommon, show a wide morphologic spectrum, often pose problems in differential diagnosis, and typically have a benign outcome. Rare tumors are associated with late recurrences and a combination of more than 3 of the 5 features listed above predicted aggressive behavior in this series.

Germ Cell Tumors of the Ovary: A Review

Ovarian germ cell tumors are a diverse group of benign and malignant neoplasms that occur in a wide age range, but with a predilection for younger age group. The majority are represented by the frequently encountered mature cystic teratomas. Malignant germ cell tumors are uncommon, and in some cases have a characteristic clinical presentation. However, from a histologic standpoint these tumors can sometimes be challenging to diagnose due to overlapping morphology with epithelial, and in some cases sex cord tumors. In these cases, a panel of immunohistochemical stains often facilitates the correct diagnosis. This review article discusses the clinicopathologic findings and pertinent ancillary studies of both common and uncommon germ cell tumors of the ovary.

Embryonal Rhabdomyosarcoma of the Uterine Cervix: A Clinicopathologic Study of 94 Cases Emphasizing Issues in Differential Diagnosis Staging, and Prognostic Factors

Embryonal rhabdomyosarcoma of the uterine cervix (cERMS) is rare and frequently associated with DICER1 mutations. We report 94 tumors that arose in patients aged 7 to 59 (median=23) years and presented with vaginal bleeding (52), protruding vaginal mass (17), cervical polyp (8), or expelled tumor fragments per vagina (5). Nine had DICER1 syndrome, 8 of whom had other syndromic manifestations including ovarian Sertoli-Leydig cell tumor (7), multinodular goiter (3), pleuropulmonary blastoma (2), pineoblastoma (1), and osteosarcoma (1). Syndromic patients were younger than nonsyndromic patients (16 vs. 24 y). Tumor size ranged from 2 to 24 (median=4.5) cm. Ninety-two tumors were polypoid, most being grape-like (77 of 92). They were characterized by aggregates of primitive cells, almost always exhibiting a cambium layer, within a variably myxoedematous stroma and were hypocellular (63), moderately cellular (22), or hypercellular (9). Entrapped glands, typically scant, were present in 84 tumors. Primitive hyperchromatic ovoid to spindled cells with minimal cytoplasm predominated but differentiated rhabdomyoblasts with abundant eosinophilic cytoplasm (having cross-striations in 30) were seen in 83 tumors; they were often sparse but predominated in three. Nine tumors showed areas of intersecting fascicles and 4 zones with densely cellular (solid) growth. Cartilage was present in 38. Anaplasia was seen in 15 tumors, as was necrosis. Mitotic activity ranged from 1 to 58/10 high-power fields (median=8). The varied microscopic features resulted in a spectrum of differential diagnostic considerations, mainly typical and cellular forms of fibroepithelial polyps, Mullerian adenosarcoma, and other sarcomas. Follow-up was available for 79 patients ranging from 6 to 492 (median=90) months. Treatment information was available in 62 and included polypectomy in 6 patients (2 also received chemotherapy), limited resection in 26 (14 also received chemotherapy), hysterectomy in 29 (15 with adjuvant chemotherapy), and biopsies only in 1 (with chemotherapy). Staging was possible in 56 tumors; according to the "uterine sarcoma" system (tumor size and extent) they were: stage I (10/56; could not be further subclassified as size not available), IA (22/56), IB (18/56), IIA (2/56), IIB 3/56), IIIC (1/56). According to the "adenosarcoma" system (depth of invasion and extent) they were: stage IA (26/56), IB (14/56), IC (10/56), IIA (2/56), IIB (3/56), IIIC (1/56). Eight patients had local recurrence following incomplete excision (10%). Eleven of 79 patients had extrauterine recurrences (14%) and 9 died of disease (11%). Older age was associated with extrauterine recurrence (median 44 vs. 22; P=0.002) and decreased disease-specific survival (median 44 vs. 22; P=0.02). For patients with tumors initially confined to the cervix, the adenosarcoma staging system was superior to the uterine sarcoma staging system for predicting survival (P=0.02). Three patients with DICER1 syndrome who underwent fertility-preserving surgery developed a second primary cERMS 7, 7, and 12 years after their primary tumor. All 9 patients with DICER1 syndrome had tumors confined to the cervix and none died of disease. This study highlights the intriguing clinical aspects of cERMS including its long-known tendency to occur in the young but also more recently appreciated association with DICER1 syndrome. Establishing the diagnosis may still be difficult because of the hazard of sampling a neoplasm which in areas may appear remarkably bland and also because of its potential confusion with other neoplasms. This study indicates that this tumor has a good prognosis at this site and in selected cases a conservative surgical approach is a realistic consideration.

Addressing the diagnostic and therapeutic dilemmas of ovarian immature teratoma: Report from a clinicopathologic consensus conference

Ovarian immature teratoma is a rare subtype of germ cell tumour that can be pure or associated with non-teratomatous germ cell tumour elements and is graded based on extent of the immature neuroectodermal component. Immature teratoma (IT) can also be associated with somatic differentiation in the form of sarcoma, carcinoma, or extensive immature neuroectodermal elements and may produce low levels of serum alpha-fetoprotein. Variable interpretation of these issues underlies diagnostic and management dilemmas, resulting in substantial practice differences between paediatric and adult women with IT. The Malignant Germ Cell International Consortium (MaGIC) convened oncologists, surgeons, and pathologists to address the following crucial clinicopathologic issues related to IT: (1) grading of IT, (2) definition and significance of 'microscopic' yolk sac tumour, (3) transformation to a somatic malignancy, and (4) interpretation of serum tumour biomarkers. This review highlights the discussion, conclusions, and suggested next steps from this clinicopathologic conference.

Germ cell tumors with neuroglial differentiation do not show molecular features akin to their central nervous system counterpart: experience from extra-gynecological sites

Teratomas with secondary somatic malignancy showing neuroglial differentiation (central nervous system (CNS)-type tumors) arising from a glial or neuroepithelial component is a very uncommon event and primarily described in the ovary. We aimed to describe the morphological spectrum and molecular features of CNS type of neuroepithelial tumors arising from the germ cell tumors (GCT) in the extra-gynecological sites. All cases of teratoma and mixed GCT arising from the non-gynecological sites over 7 years were screened for CNS type of neuroepithelial tumors. Detailed histological and immunohistochemical analysis was performed. IDH1 and 2 sequencings were performed in the glial tumors. Fluorescent in situ hybridization (FISH) was performed for EWSR1 rearrangement, 19/19q co-deletion, CDKN2A homozygous deletion, EGFR amplification, and C19MC amplification, wherever required. Out of 302 GCTs examined, the neuroglial tumor was detected in 15 cases. It included nine cases of glial tumors (including one pilocytic astrocytoma (grade I), two diffuse astrocytomas (grade II), one oligodendroglioma (grade II), one gemistocytic astrocytoma (grade II), three anaplastic astrocytomas (grade III), and one case of glioblastoma (grade IV)) and six cases of the embryonal tumor with multilayered rosettes (ETMR). None of the gliomas showed IDH mutation by immunohistochemistry or sequencing. The ETMR cases did not show Lin28 expression or C19MC amplification. To conclude, the spectrum of neuroglial tumors arising from teratoma in the extragonadal sites is vast and most commonly includes glial neoplasms and embryonal tumors. Our findings indicate that the genotype and pathogenesis of tumors with neuroglial differentiation in teratoma are distinct from their CNS counterpart.

Desmoplastic Small Round Cell Tumor of the Uterus: A Report of Molecularly Confirmed Case with EWSR1-WT1 Fusion

We report a case of a 49-year-old female with desmoplastic small round cell tumor of the uterus (DSRCT). Histologically, in some areas the tumor showed typical features with ample desmoplastic stroma, while in other areas the tumor cells diffusely infiltrated myometrium with only focal desmoplastic reaction. Immunohistochemically, the tumor cells showed diffuse positivity for desmin, CD56, CD57, EMA and cyclin D1. Focal positivity was present for antibodies against cytokeratin AE1/3, BerEP4, NSE, IFITM1 and CD10. The WT-1 antibody (against the N-terminus) showed cytoplasmic positivity in some tumor cells, while the nuclei were negative. P53 expression was wild-type. The Ki-67 index (MIB1 antibody) was about 55%. Other markers examined including transgelin, myogenin, synaptophysin, chromogranin, h-caldesmon, PAX8, and CD117 were all negative. NGS analysis revealed a fusion transcript of the EWSR1 and WT1 genes. DSRCT of the uterus is a rare neoplasm, as only two cases have been reported so far. However, only one of these cases was examined molecularly with a confirmation of the characteristic EWSR1-WT1 fusion. We report a second case of molecularly confirmed DSRCT of the uterus and discuss its clinical features, differential diagnosis and the significance of molecular testing.

NEUROECTODERMAL ELEMENTS ARE PART OF THE MORPHOLOGICAL SPECTRUM OF DICER1-ASSOCIATED NEOPLASMS

Many sarcomas with DICER1 pathogenic variants (PVs) exhibit a characteristic morphology, including a subepithelial layer of malignant mesenchymal cells, areas of rhabdomyoblastic differentiation and cartilaginous and/ or osseous elements. We report 5 DICER1-associated neoplasms (1 moderately to poorly differentiated Sertoli Leydig cell tumour and 4 sarcomas) containing variable amounts of neuroectodermal elements. The neoplasms predominantly involved or were in close proximity to the female genital tract (ovary, uterine corpus, abdominal and pelvic cavity) and occurred in females aged 14 months to 54 years. The neuroectodermal elements were characterised by solid and tubular/ rosette-like patterns and variable immunoreactivity with SALL4 and neuroendocrine markers. In some cases, the neuroectodermal component was focal while in others it was exclusive. In one case, the focal neuroectodermal component within an ovarian Sertoli Leydig cell tumour resulted in extraovarian metastasis. In reporting these cases, we suggest that neuroectodermal elements, including pure neuroectodermal tumours, are part of the morphological spectrum of DICER1-associated neoplasms. It is important that pathologists recognize that a neuroectodermal component (often admixed with other elements) may be a feature of such neoplasms. This will facilitate appropriate tumour and/ or germline testing which could lead to the identification of germline DICER1 PVs (DICER1 syndrome). Three of the patients we report were subsequently shown to have a germline DICER1 PV.

Uterine Primitive Neuroectodermal Tumor

Uterine primitive neuroectodermal tumors (PNETs) are rare entities, with only around 70 cases published in the literature. Most of them are diagnosed in advanced stages with rapid progression and poor prognosis. Herein, we present a case of a 71-year-old patient with postmenopausal metrorrhagia and an ultrasound finding of endometrial thickening. The pathological diagnosis after an endometrial biopsy showed PNET. In the study of extension, possible distant dissemination with infiltration of the sigmoid and liver was observed. Chemotherapy treatment was proposed, but not begun due to the rapid progression of the disease. Four months after the initial diagnosis, the patient died of multiple organ failure. While there is no optimal chemotherapy treatment regimen for PNET, some studies have reported encouraging results. It is necessary to publish more studies emphasizing the follow-up and survival of the disease to establish which may be the best treatment option and thus improve the current poor prognosis.

Uterine carcinosarcoma: An overview

Uterine carcinosarcoma (UCS), also known as malignant mixed Müllerian tumor, is a rare gynecological malignancy characterized by poor prognosis. This "biphasic" neoplasm presents an admixture of epithelial and mesenchymal/sarcomatoid tumor cells which partially share their molecular signature and exhibit a typical epithelial-to-mesenchymal transition gene expression profile. Due to the rarity of this cancer, at present there is a scarcity of specific treatment guidelines. Surgical resection remains the best curative option for localized disease, whereas the addition of peri-operative radiotherapy, chemotherapy and chemoradiation has been shown to further improve disease outcomes. In the metastatic setting, palliative chemotherapy is currently the treatment of choice, although no consensus exists about the best regimen to be delivered. Besides standard treatment options for the advanced disease, mechanistic insights into UCS pathogenesis and identification of its histopathological and molecular features boosted the development of novel, and potentially more effective, therapeutic agents, that will be here discussed.

Pure large cell neuroendocrine carcinoma originating from the endometrium: A case report

BACKGROUND

Large cell neuroendocrine carcinoma (LCNEC) of the endometrium is an uncommon and highly aggressive tumor that has not been comprehensively characterized. We report a case of pure endometrial LCNEC and review the current literature of similar cases to raise awareness of the histological features, treatment, and prognosis of this tumor.

CASE SUMMARY

We report the case of a 73-year-old woman who presented with irregular postmenopausal vaginal bleeding. Ultrasonography showed an enlarged uterus and a 5.1 cm × 3.3 cm area of medium and low echogenicity in the uterine cavity. Biopsy by dilatation and curettage suggested poorly differentiated carcinoma. Magnetic resonance imaging revealed a heterogeneously enhanced uterine tumor with diffuse infiltration of the posterior wall of the uterine myometrium and enlarged pelvic lymph nodes. The patient underwent a hysterectomy and bilateral adnexal resection. Gross observation revealed an ill-defined white solid mass of the posterior wall of the uterus infiltrating into the serosa with multiple solid nodules on the serous surface. Microscopically, the tumor cells showed neuroendocrine morphology (organoid nesting). Immunohistochemistry revealed the tumor cells were diffusely positive for the neuroendocrine markers CD56, chromogranin A, and synaptophysin. Thus, the tumor was diagnosed as stage IIIC endometrial LCNEC.

CONCLUSION

Pathologic findings and immunohistochemistry are essential in making a diagnosis of endometrial LCNEC.

Ovarian primary primitive neuroectodermal tumor: a review of cases at PUMCH and in the published literature

Background

The pathological characteristics, treatment strategies and prognosis of ovarian primary primitive neuroectodermal tumor (PNET) were unclear due to the rarity of PNET. All cases treated at Peking Union Medical College Hospital (PUMCH) between 1975 and 2016 and published in the English literature between 1980 to 2017 were reviewed.

Results

Finally four cases from PUMCH and 15 cases in the literature were included. The median age was 25 years (range 13–79), and the median diameter of the tumors was 13.4 cm (range 5.0–30.0). The most common initial symptoms were abdominal pain, bloating and a pelvic mass. Diagnosis primarily depended on immunohistochemical and fluorescence in situ hybridization data. Treatment consisted of surgery, various chemotherapy regimens and/or radiotherapy. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 15 and 52%, respectively. For patients with OS and PFS > 12 months, the median ages were 21 years (range 13–35) and 17 years (range 13–35), respectively, while for patients with OS < 12 months and PFS < 12 months, the median ages were 48 years (range 14–79) and 25 years (range 18–79), respectively.

Conclusions

No standard therapy for ovarian primary PNET exists, and an individualized strategy is recommended. Young patients seem to have better prognoses.

High grade sarcoma, with predominant neuroectodermal and minor embryonal rhabdomyosarcomatous tumor of the uterus: A case report

Background

There have been few documented cases of combined primitive neuroectodermal and embryonal rhabdomyosarcomas (ERMS) in the uterus. Due to their rarity, there is no consensus on the optimal treatment for patients with primitive neuroectodermal tumor (PNET) and ERMS of the uterus. Studies on treatment and outcome are limited.

Case presentation

A 32 year-old female presented with heavy vaginal bleeding. Ultrasound revealed an 18 cm uterus with thickened endometrium. Histopathology revealed embryonal rhabdomyosarcoma. She underwent a total abdominal hysterectomy, bilateral salpingectomy, lymph node dissection, and omentectomy. Pathologic review confirmed a tumor with mainly central-type PNET and focally ERMS within the uterus and cervix. She was treated with adjuvant chemoradiation.

Conclusion

Treatment of the predominant tumor, PNET, should be the primary goal of therapy. Vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide with tumor directed radiation may be efficacious for the treatment of this specific high grade uterine sarcoma.

Rare case of undifferentiated uterine sarcoma with neuroectodermal differentiation and osteoclast-like giant cells

OBJECTIVE

We describe the first case of a rare undifferentiated uterine sarcoma exhibiting both neuroectodermal differentiation and osteoclast-like giant cells, and elaborate its morphology.

CASE REPORT

A 54-year-old woman presented with suprapubic pain, frequent urination, and perimenopausal abnormal vaginal bleeding. Computed tomography revealed a large heterogeneous uterine mass and multiple lung nodules. She received a staging surgery. The tumor pathology examination revealed an undifferentiated uterine sarcoma (UUS) with neuroectodermal differentiation and osteoclast-like giant cells (OGCs). The patient was managed with palliative hospice care; however, she died within 1.5 months of diagnosis.

CONCLUSION

UUSs are rare high-grade tumors observed in elderly women. These women typically present with postmenopausal bleeding and extrauterine diseases and have a poor prognosis. Neuroectodermal differentiation in UUSs has a müllerian origin. The presence of OGCs may suggest a poor prognosis; however, further studies are necessary to determine the exact nature of such neoplasms.

Uterine corpus tumor with neuroectodermal differentiation and frequent ganglion-like cells in a postmenopausal woman

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Uterine neuroectodermal tumors (NETs) are uncommon malignant neoplasm with poor prognosis.

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Ganglion-like cells with fibrillary background as major component of uterine NETs are extremely rare.

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We present a patient affected by uterine NET with frequent ganglion-like cells, resembling ganglioneuroblastoma.

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This case report is important to define the pathogenesis and establish better treatments for neuroectodermal tumors.

Clinical management of a unique case of PNET of the uterus during pregnancy, and review of the literature

RATIONALE

PNETs (primitive neuroectodermal tumors) are a family of highly malignant neoplasms characterized by small round cells of neuroepithelial origin. They usually involve bone and soft tissues, and have a higher incidence in childhood.

PATIENT CONCERNS

In this case report, we describe the obstetric and oncological outcome of a huge mass diagnosed as a leiomyoma in a 39-year-old pregnant woman who complained of low back pain, dysuria, and urinary frequency at 22 weeks of gestation.

DIAGNOSES

During the 25th week of pregnancy, the patient was referred to our hospital at night with severe anemia and suspected hemoperitoneum. She underwent an emergency caesarean section, delivering a female fetus weighing 400 g, with an Apgar score of 7 at 1 minute and 9 at 5 minutes.

INTERVENTION

During surgery, we found a huge uterine sarcoma-like metastatic tumor, invading the pelvic peritoneum and parametria bilaterally; the adnexae seemed disease-free. We performed a type B radical hysterectomy, bilateral salpingo-oophorectomy, pelvic peritonectomy, omentectomy, appendectomy, and excision of a bulky lymph node. Seven days after delivery, staging computed tomography (CT) scan demonstrated a large lombo-aortic lymph node compressing the left renal vein and we completed debulking with a second surgery, including diaphragmatic peritonectomy and excision of a huge lymph node by lombo-aortic lymphadenectomy, requiring partial reconstruction of an infiltrated renal vein.

OUTCOME

Ten days after the second surgery, echo-color Doppler showed a regular microcirculation in the left kidney. The patient was discharged after 10 days, and the baby after 1 month, both in good health.Histological examination revealed a uterine body cPNET (central primitive neuroectodermal tumor) orienting the clinical management toward chemotherapy with cisplatin and etoposide.

LESSONS

PNETs are aggressive neoplasms, usually diagnosed at an advanced stage. Due to their low incidence, universally accepted guidelines are still unavailable. Radical surgery leaving no macroscopic residual disease is mandatory in advanced stages. A good fertility-sparing procedure can be performed only in young women at early stages of disease, when the wish for childbearing is not yet fulfilled.

Primitive Neuroectodermal Tumors of the Female Genital Tract: A Morphologic, Immunohistochemical, and Molecular Study of 19 Cases

Primary primitive neuroectodermal tumor (PNET) of the female genital tract is rare, and its proper classification remains unclear. The clinical, histologic, and immunophenotypic features as well as EWSR1 rearrangement status of 19 gynecologic PNETs, including 10 ovarian, 8 uterine, and 1 vulvar tumors, are herein reported. Patient age ranged from 12 to 68 years, with a median age of 20 and 51 years among those with ovarian and uterine PNETs, respectively. Morphologic features of central nervous system (CNS) tumors were seen in 15 PNETs, including 9 medulloblastomas, 3 ependymomas, 2 medulloepitheliomas, and 1 glioblastoma, consistent with central PNET. The remaining 4 PNETs were composed entirely of undifferentiated small round blue cells and were classified as Ewing sarcoma/peripheral PNET. Eight PNETs were associated with another tumor type, including 5 ovarian mature cystic teratomas, 2 endometrial low-grade endometrioid carcinomas, and a uterine carcinosarcoma. By immunohistochemistry, 17 PNETs expressed at least 1 marker of neuronal differentiation, including synaptophysin, NSE, CD56, S100, and chromogranin in 10, 8, 14, 8, and 1 tumors, respectively. GFAP was positive in 4 PNETs, all of which were of central type. Membranous CD99 and nuclear Fli-1 staining was seen in 10 and 16 tumors, respectively, and concurrent expression of both markers was seen in both central and Ewing sarcoma/peripheral PNETs. All tumors expressed vimentin, whereas keratin cocktail (CAM5.2, AE1/AE3) staining was only focally present in 4 PNETs. Fluorescence in situ hybridization was successful in all cases and confirmed EWSR1 rearrangement in 2 of 4 tumors demonstrating morphologic features of Ewing sarcoma/peripheral PNET and concurrent CD99 and Fli-1 expression. In conclusion, central and Ewing sarcoma/peripheral PNETs may be encountered in the female genital tract with central PNETs being more common. Central PNETs show a spectrum of morphologic features that overlaps with CNS tumors but lack EWSR1 rearrangements. GFAP expression supports a morphologic impression of central PNET and is absent in Ewing sarcoma/peripheral PNET. Ewing sarcoma/peripheral PNETs lack morphologic features of CNS tumors.

Primary primitive neuroectodermal tumor of the cervix: A report of two cases and review of the literature

Peripheral primitive neuroectodermal tumor (PNET) of the cervix uteri is extremely rare. Two cases of PNET of the cervix are presented herein. Two female patients, aged 48 and 43 years, presented with irregular uterine bleeding over the course of 1 year, and increased urinary frequency for 1 month, respectively. On gynecological examination, a mass in the cervix was palpated and a biopsy performed. The findings of the initial biopsy revealed small-cell carcinoma in both patients. Following neoadjuvant chemotherapy and radiotherapy, radical hysterectomy was performed in both patients. One patient received 5 courses of consolidation chemotherapy and postoperative radiotherapy, whereas the other patient received 1 course of consolidation chemotherapy. At the time of the article submission, both patients remained disease-free at 27 and 12 months, respectively, after their initial diagnosis. Only a limited number of cases of PNET of the cervix uteri have been reported in the literature to date. Multimodal therapies, including total excision, adjuvant chemotherapy and/or radiotherapy, have been adopted to treat patients with PNET of the cervix.

Primitive neuroectodermal tumor of the uterus

•PNET of the uterus is rare and requires early diagnoses and treatment.•Molecular analysis is important to distinguish it from other tumors.•Different combinations of adjuvant chemotherapy have been report.

Neuroendocrine Carcinoma of the Endometrium: A Clinicopathologic Study of 25 Cases

Neuroendocrine carcinoma (NECa) of the endometrium is an uncommon tumor. In this study, we present the clinicopathologic features of 25 such cases. The patients ranged in age from 37 to 87 years (median, 57 y) and most commonly presented with vaginal bleeding. The tumors were either pure NECa (10) or mixed with other histotypes (15), most commonly endometrioid carcinoma. The NECas were large cell type (15), small cell type (4), or a mixture of both (6). NECa was underrecognized in 89% of referral/consultation cases. All tumors were positive for ≥1 neuroendocrine marker (chromogranin, synaptophysin, CD56). Additional immunohistochemical (IHC) studies were obtained in 18 cases, with positive results as follows: keratin cocktail (17), diffuse p16 (6), PAX-8 (6), CD117 (6), and TTF-1 (1). Mismatch-repair protein expression by IHC was abnormal in 8 of 18 cases (6 MLH1/PMS2 loss; 1 MSH2/MSH6 loss; 1 MSH6 loss). According to FIGO staging, cases were distributed as follows: I (6), II (2), III (10), and IV (7). All patients underwent surgical treatment, and 20 patients received adjuvant therapy. Twelve patients died of disease (mean survival 12.3 mo). Eleven patients were alive 5 to 134 months after diagnosis, including 7 who achieved a 5-year survival (3 stage I; 4 stage III). In summary, most of our endometrial NECas were large cell type, mixed with other histotypes, and underrecognized. These tumors tend to be PAX-8 negative and may be associated with microsatellite instability. The recognition of NECa may have an impact on the treatment of the patients affected by this disease. Although NECa usually has an aggressive behavior, 28% of our patients survived at least 5 years.

A practical approach to the diagnosis of mixed epithelial and mesenchymal tumours of the uterus

The current 2014 World Health Organization (WHO) Classification of mixed epithelial and mesenchymal tumours of the uterus includes categories of carcinosarcoma, adenosarcoma, adenofibroma, adenomyoma and atypical polypoid adenomyoma, the last two lesions being composed of an admixture of benign epithelial and mesenchymal elements with a prominent smooth muscle component. In this review, each of these categories of uterine neoplasm is covered with an emphasis on practical tips for the surgical pathologist and new developments. In particular, helpful clues in the distinction between carcinosarcoma and dedifferentiated endometrial carcinoma will be discussed. In addition, salient features to help distinguish between adenofibroma, adenosarcoma, embryonal rhabdomyosarcoma and other mesenchymal neoplasms in the differential diagnosis will be outlined. Finally, a discussion of adenomyoma and its main differential diagnostic considerations will be covered.

Central-type primitive neuroectodermal tumor of the uterus: Case report of remission of stage IV disease using adjuvant cisplatin/etoposide/bevacizumab chemotherapy and review of the literature

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Bevacizumab was an effective agent in one case of advanced uterine PNET.

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VEGF was expressed by the tumor, supporting a mechanism for effectiveness.

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Cisplatin/etoposide/bevacizumab should be further studied in clinical trials.

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Patient remains disease-free forty-eight months following intervention.

Primitive uterine neuroectodermal tumours: Two case reports

Primitive neuroectodermal tumor (PNET) arise from Kulchitsky cells and are rarely seen in the female genital tract. Differential diagnosis of PNET can be made based on immunohistochemical profiles and genetic analyses. Genital tract pNETs are very aggressive pathologies with different clinical and molecular manifestations and there are no standard guidelines for treatment. We aimed to present two cases of uterine PNETs with different symptomatology and clinical findings.

Novel treatment of a central type, primitive neuroectodermal tumor of the ovary with postoperative pediatric medulloblastoma chemotherapy regimen: A case report and review of the literature

•Central type primitive neuroectodermal tumor (cPNET) of the ovary is difficult to treat.•Etoposide, cisplatin and cyclophosphamide is a pediatric medulloblastoma regimen.•Our case with cPNET responded to this combination chemotherapy.

Papillary ependymoma of the endometrium

AIMS

To report an exceptional case of papillary ependymoma occurring in the endometrium.

METHODS AND RESULTS

A clinicopathological study was performed regarding a case of papillary ependymoma occurring in the endometrial cavity of a 61-year-old patient who had presented with a solid-type, stage III anaplastic ependymoma of the ovary, treated with cytoreductive surgery that included total abdominal hysterectomy. The uterus was enlarged and showed a dilated cavity, with broadly implanted papillary excrescences without myometrial invasion that were covered by tall, cylindrical cells. These cells had glial fibrillary acidic protein-expressing cytoplasm that was also positive for cytokeratins 7, 8, 18, and 34β-E12, epithelial membrane antigen, S100 protein, vimentin, and oestrogen and progesterone receptors.

CONCLUSIONS

Pathogenetically, the presence of this uterine ependymoma could represent either an example of multicentricity or a phenomenon of transtubal implantation of the ovarian tumour. Exceptionally, papillary ependymoma can occur in the endometrium, and may prompt differential diagnoses with other papillary endometrial tumours. Pathologists should consider this rare possibility in the differential diagnosis of papillary ovarian and endometrial lesions.

CD99 is upregulated in placenta and astrocytomas with a differential subcellular distribution according to the malignancy stage

In the present study, we searched for genes highly expressed in placenta and that could contribute to the establishment and maintenance of a malignant phenotype in different types of tumours, and in astrocytomas in particular. We employed a strategy based on the integration of in silico data from previously generated massively parallel signature sequencing and public serial analysis of gene expression databases. Among 12 selected genes, CD99 exhibited the highest relative mRNA expression in GBM compared to non-neoplastic brain tissues. In a larger cohort of astrocytic tumours, we further demonstrated increased CD99 expression in all malignant grades, with GBMs showing the highest values. These findings were confirmed at the protein level by Western blotting and immunohistochemistry. Additionally, we demonstrated the CD99 localisation profile in astrocytic tumours. Interestingly, CD99 expression was confined to the cytoplasm or membrane in more malignant astrocytomas, in contrast to non-neoplastic brain tissue or non-infiltrative pilocytic astrocytoma, which showed no obvious staining in these structures. Comparison of three GBM cell lines revealed higher CD99 expression at the membrane and higher migratory capacity in the A172 and U87MG lines, but lower CD99 expression and no migratory ability in the T98 line. Knocking down CD99 expression by siRNA decreased significantly the migration of both cell lines. These integrated CD99 gene and protein expression results suggest that CD99 expression in astrocytomas of different malignant grades might contribute to the infiltrative ability and support the importance of CD99 as a potential target to reduce infiltrative astrocytoma capacity in migration and invasion.

Use of immunohistochemistry in the diagnosis of miscellaneous and metastatic tumors of the uterine corpus and cervix

Uncommon tumors in the uterus present diagnostic challenges. In some cases, the tumor subtype is usually seen outside the gynecologic tract and the possibility of a uterine primary is not considered. In other cases, histologic overlap with more common uterine tumors leads to potential misdiagnosis. Finally, metastatic carcinoma may involve the uterus and cervix. Rarely, symptoms related to the uterine metastasis may precede diagnosis of an extrauterine primary. Without the proper clinical context, the possibility of a missed diagnosis is increased. One must first be aware of these possibilities, but immunoperoxidase studies are often necessary to confirm the diagnosis. In this review, unusual and metastatic tumors involving the uterine corpus and cervix and immunoperoxidase studies used to diagnosis such tumors are discussed.

Clinical analysis of primary primitive neuroectodermal tumors in the female genital tract

OBJECTIVE

The aim of the study was to investigate the clinical manifestations, diagnosis, treatment, and prognosis of primitive neuroectodermal tumors (PNETs) in the female genital tract.

METHODS

From April 2001 to May 2013, the clinicopathologic characteristics, treatments, outcomes, and prognosis of 11 patients with PNET in the female genital tract were analyzed retrospectively at our hospital.

RESULTS

The location of PNET in the 11 patients presented here included vulva (2 patients), cervix (2 patients), uterus and its ligament (5 patients), and the ovaries (2 patients). Ages ranged from 18 to 59 years (median, 31 years).The main clinical manifestations of PNET in the female genital tract are irregular vaginal bleeding (6 patients), pelvic mass, uterine enlargement, and rapidly increasing vulvar mass (8 patients), and vulvar pain and lower abdominal pain (5 patients). The CA125 levels of 8 patients were elevated before the operations and reduced to normal when the diseases were controlled, while the levels increased as the tumor was progressive. Results for the most commonly used immunohistochemistry studies revealed CD99 in 11 of the 11 tumors, synaptophysin in 6 of the 7 positive tumors, and neuron-specific enolase in 6 of the 6 tumors. Ten patients underwent surgical resection. Nine of them underwent preoperative or/and postoperative combination chemotherapy. The follow-up of 10 patients were available and ranged from 1 to 145 months (median, 30.5 months), 3 of whom experiencing recurrence.

CONCLUSIONS

Primitive neuroectodermal tumor is very rare and can originate from any part of the female genital tract. The tumors had different manifestations but the same pathologic features. CA125 may be an important marker for prognosis and follow-up of PNET of the female internal genital tract.

Embryonal (botryoides) rhabdomyosarcoma of the uterus harboring a primitive neuroectodermal tumor component

The association of a uterine sarcoma botryoides of the adolescence with a primitive neuroectodermal tumor is reported in a 12-year-old patient who presented with abnormal vaginal bleeding that occurred after passing per vaginam a polypoid mass. The sarcoma botryoides of the adolescence exhibited foci of cartilage and a central area of primitive neuroectodermal tumor with a trabecular, adamantiform histology and prominent angiogenesis. Primitive neuroectodermal tumor was positive for vimentin, synaptophysin, neuron-specific enolase, CD99, and SOX2 and negative for both the FLI-1 fusion protein and the rearrangement of ESWR1 gene. The neoplasm exhibited a nonaggressive behavior similar to sarcoma botryoides of the adolescence, being alive and well 3 y after its presentation. This is possibly related to its polypoid nature and the absence of invasive features at its uterine insertion level. A conservative approach without further resection and chemotherapy was indicated taking into account the patient's age.

Uterine neuroectodermal tumor with ependymoblastic features in an infant with clonal +del (2)(q11.2),-13: a possible role of increased gene dosage on 2pter-2q11.2 in the tumorigenesis

Clonal +(2)(q11.2),-13 was detected in a uterine neuroectodermal tumor with ependymoblastic features arising in an infant. The tumor expressed vimentin, nestin, CD56, CD99, microtubule-associated protein 1B (MAP 1B), focally microtubule-associated protein 2 (MAP 2), synaptophysin, neuron-specific enolase, and, very focally, epithelial membrane antigen. Because trisomy 2 was previously detected in a medulloepithelioma of pelvic soft tissue and in several neuroectodermal tumors of the central nervous system, this finding is indicative of a possible role of increased dosage of gene(s) on chromosome 2 in the tumorigenesis of these neoplasms and of their histogenetic relatedness.

Primary primitive neuroectodermal tumor of the cervix confirmed with molecular analysis in a 23-year-old woman: A case report

Primitive Neuroectodermal Tumor (PNET) of the genital tract is very rare, especially in the cervix. A case report of a young woman with a diagnosis of PNET originating from the uterine cervix is presented here. A 23-year-old woman presented with abnormal uterine bleeding and sharp lower abdominal pain of two months duration. CT and MRI of the abdomen and thorax revealed the presence of a large mass in the uterine cervix, enlarged pelvic lymph nodes and broncho-pulmonary infiltrations with regional nodes. Pathological examination of the tumor revealed a malignant neoplasm composed predominantly of small cells, immunohistochemically positive for CD99, vimentin and c-Kit. Molecular testing demonstrated the expression of EWS/FLI1 fusion transcripts corresponding to the t(11;22)(q24;q12) translocation, which confirmed the diagnosis of PNET of the uterine cervix. Despite surgical excision and administration of the first cycle of adjuvant chemotherapy, the patient died from multiple-organ failure and cardiac arrest. PNET arising from the genital tract, especially in the uterine cervix, is very rare and presents a diagnostic challenge. A timely confirmation with molecular analysis is essential for the diagnosis of such a tumor at an unusual site as in the present case.

Malignant peripheral nerve sheath tumor with primitive neuroepithelial differentiation in an adult: a case report

Primitive neuroepithelial differentiation in malignant peripheral nerve sheath tumors (MPNSTs) has been reported in children but is extremely rare in adults. The authors report the case of a 70-year-old woman who presented with swelling of the right leg of 1-month duration. Fine-needle aspiration cytology was suggestive of a benign peripheral nerve sheath tumor. Histopathological examination of the excised mass revealed a MPNST with spindle-cell areas and a few round-cell areas with rosettes. The spindle cells showed positive immunoreactivity for S-100 protein and vimentin and negativity for desmin, confirming their nerve sheath origin. The round cells were immunoreactive for synaptophysin and chromogranin, indicating primitive neuroepithelial differentiation. These cells did not stain for CD99, which is consistently expressed by the cells of primitive neuroectodermal tumors (PNETs) of bone and soft tissue but not by central nervous system (CNS) PNETs or medulloblastomas. In this case, the PNET-like focus resembled a CNS-PNET.

Endometrial carcinomas: a review emphasizing overlapping and distinctive morphological and immunohistochemical features

This review focuses on the most common diagnostic pitfalls and helpful morphologic and immunohistochemical markers in the differential diagnosis between the different subtypes of endometrial carcinomas, including: (1) endometrioid versus serous glandular carcinoma, (2) papillary endometrioid (not otherwise specified, villoglandular and nonvillous variants) versus serous carcinoma, (3) endometrioid carcinoma with spindle cells, hyalinization, and heterologous components versus malignant mixed müllerian tumor, (4) high-grade endometrioid versus serous carcinoma, (5) high-grade endometrioid carcinoma versus dedifferentiated or undifferentiated carcinoma, (6) endometrioid carcinoma with clear cells versus clear cell carcinoma, (7) clear cell versus serous carcinoma, (8) undifferentiated versus neuroendocrine carcinoma, (9) carcinoma of mixed cell types versus carcinoma with ambiguous features or variant morphology, (10) Lynch syndrome-related endometrial carcinomas, (11) high-grade or undifferentiated carcinoma versus nonepithelial uterine tumors. As carcinomas in the endometrium are not always primary, this review also discusses the differential diagnosis between endometrial carcinomas and other gynecological malignancies such as endocervical (glandular) and ovarian/peritoneal serous carcinoma, as well as with extra-gynecologic metastases (mainly breast and colon).

Protein expression and gene promoter hypermethylation of CD99 in transitional cell carcinoma of urinary bladder

PURPOSES

To investigate the significance of CD99 protein expression and gene promoter hypermethylation status in urinary bladder carcinoma and its correlation with the histopathologic parameters.

MATERIALS AND METHODS

CD99 protein expression was determined by immunohistochemical staining in a series of 100 cases of transitional cell carcinomas (TCC) and 35 cases of normal urinary bladder tissues, and the methylation status of CD99 gene promoter was studied by using methylation-specific PCR and DNA sequencing.

RESULTS

The positive rate of CD99 protein expression was 62% (62/100) in TCC tissues, it was lower than in normal urinary bladder epithelia (97.1%, 34/35). Gene promoter hypermethylation of CD99 was observed in 26 of 82 (31.7%) cases, and none of the detected ten cases of normal transitional epithelia tissues showed CD99 methylation. CD99 hypermethylation was significantly associated with CD99 protein down-regulation in TCC (P < 0.001). Both the decreased protein expression and the higher methylated frequency of CD99 in TCC of urinary bladder were significantly correlated with the clinical stage, pathological stage, and histological grade.

CONCLUSIONS

The down-regulation of CD99 protein expression is a critical event in the progress of TCC, especially in advanced stage, and it can be explained by the presence of CD99 gene promoter hypermethylation in TCC. And both CD99 protein expression and gene promoter hypermethylation have clinical significance and implication for the diagnosis and target therapy for TCC.

Heterologous and rare homologous sarcomas of the uterine corpus: a clinicopathologic review

Pure sarcomas of the uterine corpus are uncommon, constituting less than 3% of all malignancies at this site, and most of them are leiomyosarcomas and endometrial stromal sarcomas. Rare histotypes of homologous sarcomas and heterologous sarcomas are occasionally encountered, and the absence of significant accumulated experience with these histotypes at this location may potentially raise diagnostic and patient management difficulties. In this article, the clinicopathologic attributes of all earlier reported sarcomas of the uterine corpus other than leiomyosarcomas and endometrial stromal sarcomas are summarized. Included are embryonal rhabdomyosarcoma, pleomorphic rhabdomyosarcoma, angiosarcoma, alveolar soft part sarcoma, malignant perivascular epithelioid cell tumors (PEComas), osteosarcoma, chondrosarcoma, liposarcomatous tumors, malignant extrarenal rhabdoid tumors, Ewing sarcoma/primitive neuroectodermal tumor, and other rare histotypes. Embryonal rhabdomyosarcoma (20%), Ewing sarcoma/primitive neuroectodermal tumor (17%), angiosarcoma (14%), and pleomorphic rhabdomyosarcoma (13%) appeared to be more common than the others, although there was no single overwhelmingly prevalent histotype in the group. A subset, including embryonal rhabdomyosarcoma, alveolar soft part sarcoma, and PEComas, peak in the premenopausal years, but most of the others were observed in postmenopausal women. Favorable outcomes have been reported for the patients diagnosed with alveolar soft part sarcoma, and the prognosis for their counterparts with PEComa remains a matter of debate. Multimodal therapeutic approaches to contemporary patients with embryonal rhabdomyosarcomas have resulted in significantly improved outcomes. Unfortunately, most of the other sarcomas have been associated with rapid tumor progression and unfavorable patient outcomes. The differential diagnosis for these sarcomas is often extensive and varies by histotype, but their accurate diagnosis fundamentally requires the careful exclusion of biphasic malignancies.

Ewing sarcoma-primitive neuroectodermal tumor of the uterus: a clinicopathologic, immunohistochemical and ultrastructural study of one case

INTRODUCTION

Ewing sarcoma-primitive neuroectodermal tumors (ES/PNET) constitute a family of neoplasms characterized by a continuum of neuroectodermal differentiation. ES/PNET of the uterus is rare. There are 43 cases published in the English literature as far as we know. We describe an additional case.

CASE REPORT

A 56-year-old woman presented with a 2-month history of irregular menopausal vaginal bleeding. After surgical excision, microscopic, immunohistochemical and electron microscopic examination suggested the diagnosis of ES/PNET. The patient underwent combined chemotherapy consisting of ifosfamide, etoposide, and cisplatin. She was alive with no evidence of recurrence or metastasis after 41 months of the initial operation.

DISCUSSION

In spite of the rarity of ES/PNET, we should consider it in the differential diagnosis of small cell neoplasms of the uterus.

Uterine primitive neuroectodermal tumor with adenosarcoma: a case report

Introduction

Primitive neuroectodermal tumor of the uterus is extremely rare. They occur as either pure primitive neuroectodermal tumors or admixed with neoplasms of mullerian origin.

Case presentation

A case of uterine primitive neuroectodermal tumor with adenosarcoma in a 50-year-old Asian Indian woman is presented. Histologically, the neoplasm displayed perivascular pseudorosettes and occasional Homer-Wright rosettes. A strong positivity for neuronspecific enolase and synaptophysin was noted, while chromogranin and CD99 were negative. Merging imperceptibly with the neuroectodermal components were the areas of adenosarcoma.

Conclusion

To the best of our knowledge, this report represents the second case of a uterine primitive neuroectodermal tumor with an admixed adenosarcoma.

Endometrial endometrioid adenocarcinoma associated with primitive neuroectodermal tumour of the uterus: a poor prognostic subtype of uterine tumours

Uterine primitive neuroectodermal tumours are extremely rare tumours. They can occur in pure form or combined with another component including endometrioid adenocarcinoma. We aimed to review the clinical impact of neuroectodermal phenotype in uterine tumours, after we recently diagnosed one such case. A 58-year-old female presented with irregular vaginal bleeding. Ultrasonography and CT showed the presence of a large uterine mass with irregular contours. At laparotomy it was found to extend to the right ureter, sigmoid colon and some small intestinal loops. Microscopic examination revealed that the tumour consisted of an endometrioid adenocarcinoma component merging with an extensive neuroectodermal component. No EWSR1 or FUS rearrangement was found in the two tumour components. The patient received two courses of chemotherapy but died 11 months after the initial diagnosis. We reviewed the morphological and molecular criteria for the diagnosis of uterine primitive neuroectodermal tumours published in the literature. We conclude that regardless of the detection of an EWSR1 rearrangement, the presence of a neuroectodermal differentiation component in these rare uterine tumours is a marker of aggressive behaviour, and its presence should be highlighted in the diagnosis.