Low-grade endometrial stromal sarcoma with sex cord-like differentiation metastatic to the thoracic spines

We report a case of monostotic low-grade stromal sarcoma (ESS) with sex cord-like elements metastatic to the thoracic spines, which to the best of our knowledge has not previously been documented. A 48-year-old female who had undergone total abdominal hysterectomy for low-grade endometrial stromal sarcoma 7 years previously presented with insidious onset of severe back pain of 2 months' duration. Magnetic resonance image (MRI) showed involvement of the eleventh and twelfth thoracic vertebral bodies. Decompression at the level of T10-12 was performed. Histologically, the laminae of thoracic vertebrae 11 and 12 were replaced by sheets of ovoid cells with plump nuclei intermixed with anastomosing trabeculae, cords and small nests, reminiscent of a sex-cord stromal tumor pattern. The tumor cells showed diffuse nuclear immunostaining for estrogen receptors (ER) and progesterone receptors (PR), as well as membranous immunostaining for CD10. The immunostaining for smooth muscle actin was focal and sparse. These findings confirmed the diagnosis of metastatic low-grade ESS with sex cord-like differentiation. Low-grade ESS with sex cord-like differentiation is an uncommon tumor which rarely metastasizes to the bone, and use of a panel of ER, PR, CD10, actin, cytokeratin and inhibin immunostains is essential to establish the diagnosis.     

High‐grade endometrial stromal sarcoma with smooth muscle and skeletal muscle differentiation: Report of a case with cytomorphologic and immunocytologic analysis

We report a case of high‐grade endometrial stromal sarcoma with cytological and immunocytochemical findings. Cytologically, major tumor cells showed round‐to‐short spindle shapes with round‐ to oval‐shaped nuclei and moderately abundant delicate cytoplasm. Tumor cells with tapered shapes and eccentric nuclei were also observed. A few spindle cells having enlarged cigar‐shaped nuclei with conspicuous nucleoli and delicate wispy cytoplasm, which resembled leiomyosarcoma, were intermingled. One rhabdomyoblast cell with both α‐sarcomeric muscle actin and myoglobin was also observed. Most of the tumor cells, including the leiomyosarcomatous spindle cells, were positive for CD10, and negative for desmin and h‐caldesmon. Accordingly, when relatively monotonous round‐to‐short spindle tumor cells and taper‐shaped tumor cells are observed in the female genital tract, high‐grade endometrial stromal sarcoma should be considered in the differential diagnosis. Immunocytochemistry contributed to the correct diagnosis. This case was high‐grade endometrial stromal sarcoma with smooth muscle and skeletal muscle differentiation. Diagn. Cytopathol. 2010. © 2010 Wiley‐Liss, Inc.     

Pulmonary metastases of uterine endometrial stromal sarcoma: diffuse micronodular and ground glass opacities: a case report

Pulmonary metastases of uterine endometrial stromal sarcoma (ESS) are uncommon. The patterns of uterine ESS metastasis to the lung are multiple pulmonary nodules, single nodule, or cystic lesions. Pulmonary intraalveolar micronodular metastases of uterine ESS are unusual and have not been reported. We experienced a case of metastatic uterine ESS presenting as pulmonary diffuse micronodules with ground glass opacities on chest computed tomography of a 37-yr-old woman who previously underwent hysterectomy due to low grade ESS of the uterus four years ago. The histologic findings of video assisted thoracotomy biopsy showed numerous intraalveolar polypoid micronodules protruding from the alveolar septums. All tumor nodules were composed of short spindle cells arranged in ill-defined whorls, and nuclear feature and sparse cytoplasm were seen in uterine ESS. Immunohistochemically, these cells showed strong nuclear staining for estrogen receptor and progesterone receptor, and diffuse cytoplasmic staining for CD10.     

Low-grade endometrial stromal sarcoma with intracardiac extension. Evolution of extensive smooth muscle differentiation and usefulness of immunohistochemistry for its recognition and distinction from intravenous leiomyomatosis.

This case, a rare example of low-grade endometrial stroma sarcoma with extensive smooth muscle differentiation which extended to the inferior vena cava and cardiac chambers closely resembling intravenous leiomyomatosis grossly and microscopically, illustrates the importance of extensive sectioning and the usefulness of immunohistochemistry. Although spindle cell components arranged in interlacing bundles consistent with smooth muscle differentiation were recognizable in the primary tumor (on retrospective review), extensive smooth muscle differentiation in the recurrent tumors masked prototypical morphologic features of stromal sarcoma and only small neoplastic stromal components were preserved in limited areas, leading to initial failure to distinguish the lesion from intravenous leiomyomatosis. The immunophenotyping disclosed two distinct cell populations in the tumor: i.e. vimentin-positive and smooth muscle marker negative stromal cells, and vimentin-negative spindle-shaped desmin-positive smooth muscle cells. Our observation suggests that the predominance of a smooth muscle component in such a tumor can be misleading and does not always warrant a diagnosis of intravenous leiomyomatosis, nor does it predict a benign clinical course. This case also provides an insight into the relationship of the endometrial stroma and myometrium, and their cell of origin and the histogenesis of endometrial stromal sarcoma.     

子宫内膜间质肉瘤9例临床病理分析

目的 探讨子宫内膜间质肉瘤(endometrial stromal sarcoma,ESS)的临床病理特征、诊断、鉴别诊断及预后.方法 对9例ESS患者进行临床、病理资料分析、免疫组化检测及随访.结果 患者年龄39～64岁,中位46.3岁.临床主要表现为阴道流血及子宫增大/占位.肿瘤直径2.3～11 cm,平均4.6 cm.光镜下8例呈低度恶性子宫内膜间质肉瘤(low grade endometrial stromal sarcoma,LGESS),均由类似增殖期子宫内膜间质肿瘤细胞构成,细胞密集,异型性不明显,呈不规则舌状或岛状浸润肌层,并伴较多薄壁螺旋小血管;1例为高度恶性子宫内膜间质肉瘤/未分化子宫内膜肉瘤(high grade endometrial stromal sarcoma/undifferentiated endometrial sarcoma,HGESS/UES),肿瘤细胞直接替代子宫肌层,具有明显的细胞异型性,无LGESS常见的螺旋小血管.免疫组化检测显示肿瘤细胞CD10、vimentin均阳性,PR、ER大部分阳性,SMA和desmin及h-Caldesmon为极少数局灶阳性,S-100、CD34均阴性.术后随访7例(平均53个月),只有1例HGESS/UES死亡.结论 ESS是女性生殖道很少见的一种恶性肿瘤,恶性度相差很大.确诊主要依靠其临床病理特点,并辅以免疫组化标记综合分析.诊断时要与子宫内膜间质结节、平滑肌肿瘤、低分化癌等鉴别.     

Endometrial stromal tumor with limited infiltration and probable extrauterine metastasis: report of a case

Endometrial stromal nodule (ESN) is a tumor composed of cells closely resembling those of the endometrial stroma with minimal cytologic atypia. The most important criterion for the differential diagnosis from the endometrial stromal sarcoma (ESS) is a well-defined noninfiltrative expansile border. However, the definition of the ESN also includes a tumor with the presence of focal irregularities or fingerlike projections of the margin into the adjacent myometrium, none of which exceeds 2 to 3 mm. In some cases, however, it is difficult to differentiate marginal irregularities of ESN from "true invasion" of ESS. We described a case of extrauterine ESS that was associated with small intramyometrial stromal lesions with limited infiltration. The intramyometrial lesion could be definitionally categorized as ESNs. However, peritumoral fibroblastic band and inflammatory stromal reactions, irregular fingerlike projections, and multiple concurrent extrauterine ESS strongly suggested that these were small primary focus of ESS mimicking ESN. We propose that the patient with endometrial stromal tumor with limited infiltration should be more carefully followed than the usual ESN for possible metastasis and that a hysterectomy with meticulous histological examination of the specimen be performed before a diagnosis of primary extrauterine ESS is made, even in a case showing a grossly or radiologically normal uterus.     

Aspiration biopsy cytology of metastatic endometrial stromal sarcoma and extragenital mixed mesodermal tumor

Aspiration biopsy from metastatic tumors in two cases of endometrial stromal sarcoma and one case of endometrial adenosarcoma revealed malignant endometrial stromal cells with ill-defined cytoplasm and round or oval hyperchromatic nuclei showing irregular chromatin clumping and conspicuous nucleoli. They were seen mainly in clusters. Aspirate from a metastatic tumor of a mixed mesodermal tumor arising from the omentum showed similar malignant endometrial stroma cells, irregular tight clusters of malignant glandular cells having scanty but well-defined cytoplasm and vesicular nuclei with conspicuous nucleoli, and fragments of atypical smooth muscle tissue. The diagnostic malignant endometrial stromal cells in those reported cases did not display any distinctive cellular features permitting their cytologic identification. They were difficult to differentiate from those of other types of sarcoma. In a clinical setting, with a known primary endometrial stromal sarcoma or mixed mesodermal tumor, however, a cytodiagnosis of its metastases may be suggested when malignant endometrial stromal-cell-like cells are seen in aspirated material, oviating an open-tissue biopsy.     

Colonic low‐grade endometrial stromal sarcoma and orthotopic endometrial stromal tumor with limited infiltration sharing the JAZF1‐SUZ12 gene fusion

Endometrial stromal tumors (ESTs) are composed of cells resembling endometrial stroma, and are divided into benign and malignant types based on morphology. Endometrial stromal nodule (ESN) is a benign localized tumor, and endometrial stromal sarcoma (ESS) is an infiltrative and potentially metastatic neoplasm. A series of genetic aberrations contribute to pathological diagnosis of ESTs. At present, subsets of ESN and ESS‐low grade (ESS‐LG) are characterized as JAZF1‐SUZ12/JJAZ1 gene fusion. The ESTs that show higher grade atypia but lack nuclear pleomorphism include YWHAE‐FAM22 ESS. Here we report an unusual case of ESTs. Sudden colonic perforation occurred to the patient, and emergency surgery was performed. Pathological findings suggested metastatic ESS. Thorough medical examination of the genital organs detected a 1 cm‐sized well‐demarcated uterine tumor. Microscopically, the tumor lacked infiltrative features, conforming to the definition of ESN. Both lesions demonstrated identical cytology and shared JAZF1‐SUZ12 gene fusion. Endometriosis was not found in any areas of the resected organs, strongly suggesting that the uterine orthotopic tumor metastasized. The current case uncovered the problems of differential diagnosis between ESN and ESS‐LG. We demonstrate detailed pathological features of the two lesions, and discuss the possibility of orthotopic EST with limited infiltration to develop into ESS‐LG.     

子宫内膜间质肉瘤与转移复发瘤的形态特点

目的探讨子宫内膜间质肉瘤(ESS)和转移复发瘤组织形态与免疫组织化学染色特点,及其肿瘤分化特点和鉴别诊断。方法观察15例子宫原发ESS及4例转移复发瘤的组织形态,并用免疫组织化学EnVisonTM二步法检测CD10、平滑肌肌动蛋白(SMA)、雌激素受体(ER)、孕激素受体(PR)、AE1/3及α-抑制素的表达,以10例富于细胞平滑肌瘤作对照。结果15例患者发病年龄22～75岁(平均45岁)。组织学分型:7例经典型,3例平滑肌分化型,2例纤维黏液型,3例分化差型,细胞异型明显。4例复发转移瘤中3例组织形态与原发瘤不同。免疫组织化学染色阳性结果:在14例ESS及4例复发转移瘤中CD1015/18、SMA5/18、ER7/18、PR10/18;AE1/3和α-抑制素仅在腺样分化区阳性。平滑肌瘤对照组CD10为1/10、SMA为10/10,表达差异均有统计学意义(P<0.05)。结论ESS多向分化的特点使其呈现多样的组织形态,且转移复发瘤形态可与原发瘤不同。CD10与SMA联合应用有助于ESS的诊断和鉴别诊断。     

Malignant uterine perivascular epithelioid cell tumor: histopathologic and immunohistochemical characterization of a rare tumor in a post-menopausal woman

Background: Perivascular epithelioid cell tumors (PEComas) are rare, mesenchymal neoplasms composed of epithelioid cells exhibiting myogenic and melanocytic differentiation. The uterus is an infrequent site of involvement. The most common histopathologic mimics include leiomyosarcoma, endometrial stromal sarcoma, undifferentiated uterine sarcoma, and malignant melanoma. Rendering an accurate histopathologic diagnosis is essential, owing to the prognostic and therapeutic implications. Case: A 65-years-old post-menopausal woman presented with post-menopausal bleeding, abdominal pain, and heaviness for the last four months. Ultrasound abdomen revealed a large uterine mass replacing the endometrial cavity. She underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Result: Microscopically, a circumscribed tumor with tumor cells arranged in sheets and interlacing fascicles, with interspersed fine capillary network, was seen. The individual tumor cells were epithelioid to spindle with moderate pleomorphism, round nuclei, vesicular chromatin, prominent macronucleoli, and moderate cytoplasm. Mitosis was 2-3/50 HPFs. On immunohistochemistry, tumor cells were positive for HMB-45, Melan-A, and smooth muscle actin and were negative for h-caldesmon, TFE3, S-100, CD10, and pan-cytokeratin. Based on the histopathologic and immunohistochemical features, a final diagnosis of malignant uterine PEComa was rendered. Conclusions: This index report describes the characteristic histopathologic and immunohistochemical features of malignant uterine PEComa and highlights the salient features that distinguish it from other commonly encountered histopathologic mimics.     

Detection of pulmonary metastasis of low-grade endometrial stromal sarcoma 25 years after hysterectomy

Endometrial stromal sarcoma (ESS) is a rare uterine sarcoma. Low-grade ESS occasionally recurs or metastasizes after long disease-free periods, a fact that may complicate the diagnosis. Here we report a case of multiple lung metastases in a 68-year-old woman who had been disease-free for 25 years after hysterectomy for a uterine tumor. Biopsy revealed that the tumor was composed of oval cells with slight nuclear atypism but without mitotic figures, suggesting a low-grade neoplasm. Immunostaining for intermediate filaments revealed strong positivity for vimentin and weak positivity for alpha-smooth muscle actin. In addition, immunostaining for estrogen and progesterone receptors, performed under suspicion of low-grade ESS, was positive. The uterine tumor resected many years before had shown a similar morphology. Thus, it was demonstrated that the lung neoplasm was a metastatic low-grade ESS that had appeared after many disease-free years. A review of the literature revealed that this case had the longest recorded interval between the occurrence of the initial ESS and the development of distant metastases. When low-grade sarcoma appears in the lungs of female patients, it is important to consider the possibility of low-grade ESS. Detailed information on the past clinical history, together with immunostaining for estrogen and progesterone receptors, are important diagnostic keys.     

Myxoid mesenchymal tumors of uterus: endometrial stromal and smooth muscle tumors, myxoid variant

Four myxoid variant of uterine mesenchymal tumors are reported. One was a low grade stromal sarcoma with infiltrative margins and the others were well circumscribed tumors corresponding to an endometrial stromal nodule and two leiomyomas. They were hypocellular neoplasms composed of stellated cells with an abundant Alcian Blue positive myxoid matrix. The myxoid nature of the neoplasms obscured their cellular nature and made the distinction between smooth muscle and endometrial stromal tumors difficult. Endometrial stromal tumors, showed very focal areas of small basophilic cells, characteristic of endometrial stroma. The diagnosis was based on the presence of a spiral arteriolar network, a CD10 positivity as well as the absence of h-caldesmon and desmin expression. The two myxoid leiomyomas showed more spindle cells and a desmin expression while h-caldesmon was negative and CD10 focally positive in both cases. Myxoid variant of endometrial stromal tumors does not necessarily exhibit the typical morphology of endometrial stroma. They may demonstrate morphological features of smooth muscle tumors in the uterus. Also, myxoid changes in uterin smooth muscle tumors may modify the classical immunoreactivity of smooth muscle markers in these tumors and make it difficult to distinguish between benign and malignant neoplasms. An immunohistochemical panel of antibodies including CD10, h-caldesmon and desmin may help in establishing the correct diagnosis.     

Uterine epithelioid endometrial stromal sarcoma presenting as a "cervical polyp"

Although appearance of conventional uterine endometrial stromal sarcoma is easily recognized on histology, it may uncommonly assume unusual appearances such as uterine tumor resembling ovarian sex-cord tumor, thereby hindering its diagnosis. Recently, its manifestation as an epithelioid neoplasm was described. In this report, we detail yet another instance where this tumor adopted an epithelioid morphology, presenting itself as a polyp extruding from the cervical os in a 41-year-old Chinese woman. Both the polypectomy and subsequent hysterectomy specimens revealed a predominant proliferation of CD10-negative, caldesmon-negative, and CD117-positive epithelioid cells set within a stroma containing vascular proliferation resembling endometrial stromal tumor. Areas of typical low-grade endometrial stromal sarcoma containing spindle cells that were focally positive for CD10 and negative for CD117 were present in close association with the epithelioid areas. The differential diagnoses and possible implication of CD117 positivity are discussed.     

Myxoid mixed low-grade endometrial stromal sarcoma and smooth muscle tumor of the uterus. Case report

We report the case of a 73-year-old female with myxoid mixed low-grade endometrial stromal sarcoma and smooth muscle tumor of the uterus. Grossly, the tumor sized 130 x 130 x 100 mm involved the uterine corpus almost in its entirety. Histologically, the tumor consisted of two cell types. In some areas, the tumor cells showed typical features of endometrial stromal tumors and resembled stromal cells of proliferative endometrium. In other areas, however, the tumor showed smooth muscle features and consisted of larger mostly epitheloid cells with a moderate amount of cytoplasm. In all areas, myxoid changes and multiple hyalinizing giant rosettes were present. The tumor infiltrated the myometrium in a pattern typical of low-grade endometrial stromal sarcoma. Immunohistochemically, the tumor cells showed expression of vimentin, estrogen and progesterone receptors and variable expression of CD10, α-smooth muscle actin, desmin, h-caldesmon, and cytokeratin AE1/AE3. Other markers examined including CD99, α-inhibin, cytokeratin CAM5.2, S-100 protein, and HMB45 were negative. To the best of our knowledge, mixed low-grade endometrial stromal and smooth muscle tumor with myxoid changes has not been described to date.     

Endometrial stromal sarcoma arising in vaginaEndometrial stromal sarcoma arising in vagina

Endometrial stromal sarcoma (ESS) arising in the vagina is an extremely rare extrauterine endometrial stroma sarcoma, with only 4 cases reported in the literature up to date. Here we report a case of neoplasm originating from vagina. A 32-year-old woman complained of intermittent vaginal bleeding especially after intercourse. A mass with a diameter of 1.0 cm was found in the middle and upper segments of the right posterior vaginal wall. Biopsy showed ESS. Total abdominal hysterectomy, unilateral salpingo-oophorectomy (right) and partial vaginectomy were performed. No ESS lesion was found in endometrium. The patient received six courses of platinum-containing combination chemotherapy after surgery and was free of tumor 18 months after the diagnosis of ESS. The diagnosis of ESS relies on pathologic examination. CD10 is the most useful immunohistochemical marker for the diagnosis of this tumor. The mainstay treatment of ESS is surgery. Local excision and ovarian retaining may be considered in premenopausal women.     

Utility of CD10 in distinguishing between endometrial stromal sarcoma and uterine smooth muscle tumors: an immunohistochemical comparison of 34 cases.

Endometrial stromal sarcoma (ESS), uterine cellular leiomyoma (UCL), and uterine leiomyosarcoma (ULS) are composed mainly of spindle cells that express similar antigens such as desmin, smooth muscle actin (SMA), and muscle-specific actin (MSA). The differential diagnosis of an ESS versus a uterine smooth muscle tumor or an extrauterine spindle cell sarcoma can be problematic based solely on clinical presentation, histologic assessment, or routine immunohistochemistry. Recently, we reported that normal endometrium, but not myometrium, as well as five cases of ESS, were positive for CD10. We now report the results of CD10 immunohistochemistry in an additional 11 cases of ESS (total 16 cases), 10 cases of UCL, and nine cases of ULS. CD10 immunoreactivity was detected in 16 of 16 cases of ESS (100%) as compared to only 2 of 10 cases of UCL (20%) and none of nine cases of ULS (0%). We compared the utility of CD10 immunoreactivity with that of desmin, SMA, MSA, estrogen receptor (ER), and inhibin in these tumors. Although the majority of cases of UCL and ULS were positive for SMA, MSA, and desmin, a substantial portion of cases of ESS were also positive for SMA, MSA, and desmin. We conclude that in combination with SMA, MSA, and desmin, CD10 is a useful immunohistochemical marker in the differential diagnosis of ESS versus UCL or ULS.     

High grade endometrial stromal sarcoma on thinprep

High grade endometrial stromal sarcoma (HGESS) is an uncommon malignancy recently re‐defined in the new WHO classification of endometrial stromal tumors. In this article, we discuss the differential diagnoses of metastatic HGESS in a fine needle aspiration (FNA) of a lymph node and compare the cytomorphology of HGESS in ThinPrep [(TP), Hologic Inc., Boxborough, MA] to conventional smears (CS). The patient had a history of stage I HGESS, status‐post supracervical hysterectomy without regional lymph node metastases. Her post‐operative course was complicated by pelvic fluid collections and enlarging para‐aortic lymph nodes. Diff‐Quik (DQ)‐stained and Papanicolaou (Pap)‐stained smears from a para‐aortic lymph node FNA demonstrated a cellular specimen with monomorphic population of plump to oval cells with scant, wispy cytoplasm in aggregates and as single cells. The nuclei showed fine chromatin and small inconspicuous nucleoli. Compared to the CS, HGESS cells in the TP showed similar cytological features, with the exception that the nuclei were slightly smaller, hyperchromatic, and the chromatin pattern was attenuated. In the absence of prior clinical history, the cytomorphology of metastatic HGESS in a lymph node can be difficult to differentiate from a lymphoma, a variety of metastatic spindle cell tumors or metastatic carcinoma. Immunohistochemical analysis and comparison with the primary tumor can be useful in proving the nature of the malignant cells. The cytomorphology of HGESS on TP correlated well in both single cells and aggregates when compared to CS. The differences noted were decreased nuclear size, nuclear hyperchromasia, and slightly attenuated nuclear detail on TP. Diagn. Cytopathol. 2015;43:756–762. © 2015 Wiley Periodicals, Inc.     

CD10 is a sensitive and diagnostically useful immunohistochemical marker of normal endometrial stroma and of endometrial stromal neoplasms

AIMS: The CD10 antigen is expressed in acute lymphoblastic leukaemia and follicle centre cell lymphoma. A recent study investigating the expression of CD10 in a wide range of non-haematopoietic neoplasms found positive staining in a small number of endometrial stromal sarcomas as well as in normal endometrial stroma. The present study aimed to ascertain whether CD10 positivity is indeed found in normal endometrial stroma and endometrial stromal neoplasms. Staining of a range of tumours which can be confused morphologically with endometrial stromal neoplasms was also undertaken to ascertain whether antibodies against CD10 are of value in a diagnostic sense. METHODS AND RESULTS: Neoplasms included in the study were endometrial stromal nodule (n=1), low-grade endometrial stromal sarcoma (ESS) (n=13), high-grade ESS (n=6), mixed endometrial stromal-smooth muscle tumour (n=1), uterine cellular leiomyoma (n=10), uterine leiomyosarcoma (n=5), adult granulosa cell tumour (AGCT) (n=10), undifferentiated endometrial carcinoma (n=6), uterine carcinosarcoma with an endometrial stromal component (n=1) and type II uterine mesenchymal tumour with sex cord-like elements (n=1). Cases of proliferative (n=5), secretory (n=5) and atrophic (n=3) endometrium were also stained. There was positive staining of stroma but not of glands in all cases of non-tumorous endometrium. There was positive staining of the endometrial stromal nodule and of all low-grade ESS. Staining in these varied but was often diffuse and of moderate to strong intensity. There was positive staining of four of six high-grade ESS, but this was usually focal. There was also positive staining of the endometrial stromal component in the mixed endometrial stromal-smooth muscle tumour and in the uterine carcinosarcoma. Most cellular leiomyomas were completely negative although three exhibited weak positivity. There was some positivity, usually focal or weak, of three of five leiomyosarcomas. Most AGCT and undifferentiated carcinomas were completely negative although one case of each exhibited focal staining. There was focal staining of the type II uterine mesenchymal tumour with sex cord-like elements. CONCLUSION: CD10 is a reliable and sensitive immunohistochemical marker of normal endometrial stroma. Positivity, which is often strong and/or diffuse is found in endometrial stromal nodules and low-grade ESS. Positive staining with CD10, when strong and diffuse, may be useful in distinguishing these tumours from histological mimics, especially cellular leiomyoma and AGCT which are generally negative. In this situation, CD10 should be used as part of a panel which might include desmin and alpha-inhibin depending on the differential diagnosis considered. Positive staining with CD10 in a high-grade uterine sarcoma which is negative with muscle markers might indicate endometrial stromal differentiation and identify a group of neoplasms which it is correct to diagnose as high-grade ESS rather than undifferentiated uterine sarcoma.     

Myxoid endometrial stromal sarcoma of the uterus

A rare case of a myxoid type of endometrial stromal sarcoma of the uterus in a 41-year-old woman is reported. A tumor was found in the myometrium and was well circumscribed, measuring 9 x 7 x 7 cm in size. The tumor was mainly composed of a hypocellular area with tumor cells separated by prominent myxoid stroma. The tumor cells were spindle-shaped and resembled endometrial stromal cells. Numerous small thin-walled vessels were seen throughout the tumor. Immunohistochemically, the tumor cells were diffusely stained for estrogen and progesterone receptors and CD10, and focally and weakly for HHF35, alpha-smooth muscle actin and desmin, but not stained for h-caldesmon. These results indicated that the tumor originated from endometrial stromal cells. The tumor had an increased mitotic activity (MIB-1 labeling index: 1-10%), and focally showed nuclear pleomorphism. Thus, this tumor had a malignant potential and was diagnosed as a myxoid type of low-grade endometrial stromal sarcoma. The patient is currently well with no evidence of local recurrence or metastasis 21 months after the operation. This case indicates a wide morphological spectrum of endometrial stromal tumor. A myxoid endometrial stromal sarcoma should be considered in the different diagnosis of the intramural myxoid tumors in the uterus.     

Breakages at YWHAE,FAM22A,and FAM22B loci in uterine angiosarcoma: A case report with immunohistochemical and genetic analysis

Described herein is the first reported case of a uterine angiosarcoma with breakages at three loci, YWHAE (17p13), FAM22A (10q23) and FAM22B (10q22). A 62-year-old postmenopausal woman was found to have endometrial thickening of her uterus. An endometrial biopsy indicated a malignant, spindle cell neoplasm. A total hysterectomy with bilateral salpingooophorectomy was performed. Histologic examination of the uterine specimen showed a malignant tumor consisting of irregular rudimentary vascular channels and solid small nests diffusely infiltrating to the middle of the myometrial wall. The tumor cells were epithelioid, and displayed eosinophilic cytoplasm and vesicular nuclei in some areas of the tumor. Immunohistochemically, the tumor cells showed vascular differentiation; they were diffusely positive for CD31 and D2-40 but were negative for factor VIII and CD34. In the course of the procedure of differential diagnoses, we included fluorescence in situ hybridization analysis for detection of a FAM22B-YWHAE fusion gene resulting from t(10;17)(q22;p13), recently reported in a series of endometrial stromal sarcoma, and unexpectedly identified breakages at three loci, i.e. YWHAE (17p13), FAM22A (10q23) and FAM22B (10q22). Collectively, these findings suggest that abnormality in the loci of YWHAE, FAM22A and FAM22B, which are known to be associated with oncogenesis of endometrial stromal sarcoma, may contribute to the development of uterine angiosarcoma.