肾透明细胞肉瘤的临床病理及免疫表型特征

目的 探讨肾透明细胞肉瘤（clear cell sarcoma of the kidney,CCSK）的临床病理特点、免疫表型特征及鉴别诊断。方法 应用HE和免疫组化vimentin、bcl-2、desmin、S-100蛋白、CD99、CD34、CDll7、CK、EMA染色,观察2例CCSK的病理组织学形态,并复习文献。结果 镜下见瘤细胞为上皮样或短梭形,被分枝状纤维血管间质分隔成巢团状,部分区域见黏液样变性微囊肿和细胞外胶原玻璃样变类似骨样组织的硬化型等形态变异。免疫组化示：瘤细胞vimentin和bcl-2弥漫阳性,余为阴性。结论 CCSK是一种罕见的儿童期恶性肾肿瘤,诊断主要依靠组织病理学和免疫组化,熟悉其形态学变异有利于与其它类似病变如肾母细胞瘤、先天性中胚叶肾瘤、肾恶性横纹肌样瘤、原始神经外胚叶肿瘤等鉴别。     

Clinicopathologic features of renal epithelioid angiomyolipoma: report of one case and review of literatures

Epithelioid angiomyolipoma (EAML) is a rare renal mesenchymal tumor with malignant potential and is frequently associated with tuberous sclerosis complex (TSC). As metastasis of the tumor cells occur early, EAML is considered a potentially malignant tumor type and intrigues further research on it. Under the microscope, we could find the tumor was composed of atypical polygonal cells sheet mixed with classic angiomyolipoma (AML) components such as blood vessels with notable thick vascular walls, smooth muscle-like cells and adipocytes. Immunohistochemical studies showed that epithelioid cells were focally positive for vimentin, melanocytic markers (HMB-45), myoid markers (α-smooth muscle actin), CD34 and CD68; negative for cytokeratin, epithelial membrane antigen, CD10, and S-100. And the Ki67 index showed approximately 3%. Here, we report the morphological and immunohistochemical features of clinically or histologically malignant renal EAML and discuss its diagnosis, differential diagnosis and the prognosis.     

Fine‐Needle aspiration cytology of primary renal angiosarcoma with histopathologic and immunocytochemical correlation

Primary renal angiosarcoma is an extremely rare neoplasm, with fewer than 28 cases reported thus far in the English literature. We report for the first time the cytomorphology and immunocytochemistry of this tumor in liquid‐based (ThinPrep) fine‐needle aspiration (FNA) samples in correlation with the conventional cytologic and histopathologic findings. Conventional smears showed pleomorphic tumor cells focally arranged in structures suggesting anastomosing vascular channels, while ThinPrep smears were less cellular with fewer and smaller tumor cells arranged in clusters or rosette‐like formations. Immunocytochemical staining demonstrated positive results for vimentin, CD31, and CD34 and negative staining for epithelial markers, thus supporting the diagnosis of a mesenchymal tumor of vascular origin. The diagnosis of primary renal angiosarcoma was established after histopathologic evaluation of a metastatic liver nodule. The cytological differential diagnosis of this neoplasm and the utility of the ThinPrep method as a diagnostic adjunct to conventional FNA cytology are further discussed. Diagn. Cytopathol. 2014;42:872–876. © 2013 Wiley Periodicals, Inc.     

Malignant solitary fibrous tumor of pleura with focal expression of cytokeratin

Solitary fibrous tumor is a rare circumscribed neoplasm involving usually the pleura and now described in many organs and in the soft tissues with a favorable outcome when completely excised. We report herein a malignant solitary fibrous tumor of the pleura occurring in a 59-year-old woman. The tumor cells strongly expressed vimentin and CD 34. In addition a weak positive staining was obtained using CD 99 and bcl 2. A disconcerting focal immunoreactivity with cytokeratin was observed. Solitary fibrous tumor is composed of loosely arranged spindle cells of variable density and may occasionally mimic malignant mesothelioma, an hemangiopericytoma or synovial sarcoma. Immunohistochemical study is helpful demonstrating a strong positivity for vimentin and CD 34 and absence of staining for epithelial markers and S-100 protein.     

Splenic angiosarcoma: a clinicopathologic and immunophenotypic study of 28 cases.

Primary angiosarcoma of the spleen is a rare neoplasm that has not been well characterized. We describe the clinical, morphologic, and immunophenotypic findings of 28 cases of primary splenic angiosarcoma, including one case that shares features of lymphangioma/lymphangiosarcoma. The patients included 16 men and 12 women, aged 29 to 85 years, with a mean of 59 years and median of 63 years. The majority of patients (75%) complained of abdominal pain, and 25% presented with splenic rupture. The most common physical finding was splenomegaly (71%). Seventeen of 21 patients were reported to have anemia. Macroscopic examination showed splenomegaly in 85% cases. Sectioning revealed discrete lesions in 88% of cases, ranging from well-circumscribed firm nodules to poorly delineated foci of necrosis and hemorrhage associated with cystic spaces. Microscopically, the tumors were heterogenous; however, all cases demonstrated at least a focal vasoformative component lined by atypical endothelial cells. Solid sarcomatous, papillary, and epithelioid growth patterns were observed. The solid sarcomatous component resembled fibrosarcoma in two cases and malignant fibroushistiocytoma in one case. Hemorrhage, necrosis, hemosiderin, extramedullary hematopoiesis, and intracytoplasmic hyaline globules were frequently identified. A panel of immunohistochemical studies revealed that the majority of tumors were immunoreactive for at least two markers of vascular differentiation (CD34, FVIIIRAg, VEGFR3, and CD31) and at least one marker of histiocytic differentiation (CD68 and/or lysozyme). Metastases developed in 100% of patients during the course of their disease. Twenty-six patients died of disease despite aggressive therapy, whereas only two patients are alive at last follow-up, one with disease at 8 years and the other without disease at 10 years. In conclusion, primary splenic angiosarcoma is an extremely aggressive neoplasm that is almost universally fatal. The majority of splenic angiosarcomas coexpress histiocytic and endothelial markers by immunohistochemical analysis, which suggest that some tumors may originate from splenic lining cells.     

Follicular dendritic cell tumor of the gastrointestinal tract: Report of a rare neoplasm and literature review

Follicular dendritic cell (FDC) tumor is a rare neoplasm of the accessory immune system showing FDC differentiation. Histologically, a conventional type and an inflammatory pseudotumor (IPT-like) type are recognized. The etiology of FDC tumor is unknown. While rare FDC tumors were associated with hyaline-vascular Castleman's disease (HVCD), hepatosplenic IPT-like FDC tumors consistently harbor EBV infection. FDC tumors of the gastrointestinal (GI) tract and mesentery/omentum are exceedingly rare, with only 17 cases reported so far. We report an additional case of an IPT-like FDC tumor of the ileum and mesentery in a 52-year-old schizophrenic man. The tumor consisted of highly atypical multinucleated giant cells in a background of intense lymphoid infiltrate with prominent eosinophilia reminiscent of Hodgkin's lymphoma. Tumor cells were immunoreactive for vimentin, CD21, CD35, fascin, smooth muscle actin and CD68, but were negative for all lineage-specific lymphoreticular, myeloid, mesenchymal and epithelial markers. Immunostaining for HHV-8 and in situ hybridization for EBV-encoded RNA (EBER) were negative. Some mesenteric lymph nodes showed HVCD-like changes. The differential diagnostic considerations of this unusual and rare neoplasm, mainly lymphocyte-rich GI stromal tumor (GIST), malignant lymphoma and inflammatory neoplasia of diverse histogenetic types, will be discussed together with a literature review on gastrointestinal FDC tumors.     

Xanthogranulomatous cystitis imitating bladder neoplasm: a case report and review of literature

Xanthogranulomatous cystitis is a rare, benign chronic inflammatory disorder with unclear etiology. Since its similar features to bladder neoplasm, it is extremely easy to be mistaken for malignant tumor. We herein reported a case of xanthogranulomatous cystitis in a 54-year-old male who presented with low abdominal pain and painless, total macrohematuria. Microscopy showed proliferation of large foam histiocytes which expressed CD68 and vimentin. Ki-67 showed a lower proliferation index (< 10%). Histopathology and immunohistochemical findings confirmed the diagnosis. This case highlighted the significance of recognizing this unusual lesion and differentiating it from its histological mimics by immunohistochemical staining.     

Pleomorphic hyalinizing angiectatic tumor of renal hilum

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a recently described rare entity. The tumor histogenesis is proposed to be of primitive undifferentiated mesenchyme. The tumor has a predilection for the subcutaneous soft tissue especially of lower extremity, although other locations have been well documented. We report a case of PHAT arising in the hilum of the kidney, clinically mimicking an infiltrating malignant neoplasm of renal pelvis. The tumor was discovered during workup for unrelated gastrointestinal tract symptoms. Because of the location of the lesion, excision of mass and radical nephrectomy were performed. The tumor had strong immunohistochemical expression of vimentin, CD34, CD99, and vascular endothelial growth factor (VEGF). No additional lesions were documented during 3 years of follow-up. This is consistent with the current thinking that PHAT is a benign neoplasm with increased incidence of recurrence. We document the unique retroperitoneal location of this rare tumor and suggest that PHAT should be considered among the list of unusual lesions at this site.     

Embryonal (undifferentiated) sarcoma of the liver with peripheral angiosarcoma differentiation arising in a mesenchymal hamartoma in an adult patient

Embryonal (undifferentiated) sarcoma of the liver (ESL) is a rare malignant neoplasm composed of undifferentiated sarcomatous tissue. We are presenting a case of a 74-year-old woman diagnosed with an ESL arising from a mesenchymal hamartoma of the liver (MHL). Both lesions occur typically in childhood, with only rare reported cases in adults. Histologically, the mass consisted primarily of loose myxoid stroma admixed with bland spindle cells and extensive, cystic (lymphangioma-like) degeneration. However, also present peripherally were markedly atypical cells (including multi-nucleated forms) and hyaline globules. Additionally, atypical cells with a sinusoid tectorial growth pattern were identified, which were positive for CD31, CD34 and Factor VIII. The tumor cells of ESL are classically described as being negative for tissue-specific immunohistochemical markers. However our case demonstrated focal positivity for vascular markers CD31, CD34 and Factor VIII and this along with the sinusoidal tectorial growth pattern, mimicked an angiosarcoma.     

Primary peritoneal epithelioid hemangioendothelioma

Epithelioid hemangioendothelioma is an uncommon malignant vascular tumor of intermediate grade that occurs in a variety of organs and soft tissues. Diagnosis of epithelioid hemangioendothelioma is often complicated by the rarity of the tumor, and because the tumor shares many morphologic features with other peritoneal neoplasms. This report presents 3 cases of epithelioid hemangioendotheliomas arising as primary tumors of the peritoneum and reviews 7 previously reported cases to establish the demographic, clinical, morphologic, immunohistochemical, and ultrastructural features of this neoplasm. These cases demonstrate that the light microscopic features are very similar to epithelioid hemangioendothelioma arising at more conventional sites, such as the liver, that immunohistochemical analysis provides a reliable approach for confirming or establishing the diagnosis, and that at least one endothelial marker (either CD31, CD34, or factor VIII) should be positive for a definitive diagnosis. This series identifies the characteristics of peritoneal epithelioid hemangioendothelioma that can be reliably used for diagnosis.     

Solitary fibrous tumor with malignant potential arising in sublingual gland

A rare case is described of a solitary fibrous tumor (SFT) with malignant potential arising in the sublingual gland. A 59-year-old man presented with a 4-month history of a slowly enlarging painless mass in the center of the floor of the mouth. The tumor was a well-demarcated, firm mass with a multicystic lesion. The tumor exhibited highly cellular areas of spindle cells with patternless architecture alternating with hypocellular areas. The tumor cells were positive for CD34 and bcl-2 as well as vimentin, and negative for epithelial, myogenic, neurogenic and histiocytic markers. The tumor cells formed multiple satellite nodules around dilated ducts in the multicystic lesion, indicating infiltrative growth. In addition, areas exhibiting higher cellularity with increased mitoses were noticed in the satellite nodules, although cellular atypia was not obvious. These findings led to a final diagnosis of SFT with malignant potential. There has been no recurrence or metastasis for 27 months after the surgery. Solitary fibrous tumor of the salivary gland must be differentiated from various spindle cell neoplasms including myogenic, peripheral nerve sheath, fibroblastic and fibro-histiocytic spindle cell neoplasms, hemangiopericytoma and myoepithelioma. In addition to characteristic morphological features, an immunohistochemical positivity for CD34 and bcl-2 may aid in the diagnosis of SFT.     

Epithelioid haemangiosarcoma in the ocular tissue of horses

Haemangiosarcomas (HSAs) are malignant tumours of endothelial cell origin. Epithelioid HSA is a variant of the histologically conventional HSA that has little or no morphological evidence of a vascular origin and has been reported rarely in domestic animals. The following report documents six cases of equine epithelioid HSA occurring in the ocular tissues of horses with a mean age of 19.8 years at the time of diagnosis. Microscopically, all of the lesions consisted of solid sheets or cords of epithelioid cells with rare narrow clefts or small spaces containing erythrocytes that were often the only feature indicating a vascular origin. On immunohistochemistry, the neoplastic cells expressed vimentin, CD31 and factor VIII-related antigen, but not cytokeratin, indicating an endothelial nature.     

Sinonasal teratocarcinosarcoma: a clinicopathologic and immunohistochemical study of 6 cases

Teratocarcinosarcoma (TCS) is a rare and unusual malignant neoplasm of the sinonasal tract with a heterogenous morphology and an aggressive behavior. Patients are predominantly adults with a male predominance. The aim of this study was to describe clinicopathologic and immunohistochemical features of 6 cases of TCS. The ages ranged from 18 to 67 years (mean, 33 years) with a male-to-female ratio of 5:1. Most tumors were located in the nasal cavity. Nasal obstruction and epistaxis were the common presenting symptoms. Histologically, all tumors exhibited a heterogeneous morphology with varying proportions of benign and malignant epithelial, mesenchymal, and neuroepithelial elements. Adenocarcinoma was the malignant epithelial component in all cases. The mesenchymal elements were composed of benign to malignant spindle cells. Osteosarcomatous areas were seen in 2 cases and rhabdomyosarcoma in 1 case. Rhabdoid differentiation was also seen in 1 case. Immunohistochemical stains CKAE1/AE3 and CK Cam 5.2 were positive in the epithelial elements, vimentin in mesenchymal, and CD56 and neuron-specific enolase in neuroepithelial elements. Follow-up was available in 4 patients and ranged from 21 to 40 months (mean, 31 months). Lung and dura metastasis, respectively, were seen in 1 patient each. However, all 4 patients are alive and free of disease to date. In conclusion, TCS is a rare but highly malignant tumor with aggressive behavior characterized by benign and malignant epithelial, mesenchymal, and neuroepithelial components. Two patients in our series were younger than 20 years. The occurrence of rhabdoid differentiation and osteosarcomatous component seen in our series were rarely described in literature. Recognition of all the components requires adequate sampling, which is crucial for a correct diagnosis.     

肝脏单形性上皮样血管平滑肌脂肪瘤

目的：探讨肝脏单形性上皮样血管平滑肌脂肪瘤的临床病理学特征及诊断、鉴别诊断要点。方法：对1例单形性上皮样血管平滑肌脂肪瘤进行临床病理学分析及免疫组织化学研究。结果：肝脏单形性上皮样血管平滑肌脂肪瘤临床多无症状,光镜下单形性上皮样血管平滑肌脂肪瘤由形态多样的上皮样细胞构成,胞质透明或嗜酸,无脂肪组织及异常血管;免疫表型;HMB45阳性,SMA及vimentin部分阳性,desmin少数阳性,S－100蛋白弱阳性,cytokeratin及AFP阴性,CD34血管内皮细胞阳性。结论：肝脏单形性上皮样血管平滑肌脂肪瘤是极为罕见的间叶性肿瘤,组织起源至今不明,其诊断及鉴别诊断主要依靠病理组织学及免疫组织化学。     

Myeloid sarcoma of the urinary bladder and epididymis as a primary manifestation of acute myeloid leukemia with inv(16)

Myeloid sarcoma (MS) of the lower urinary tract is rare. We describe a 47-year-old man with hematuria, who was subsequently found to have MS involving bladder and epididymis. The neoplasm was composed predominantly of blasts that expressed CD68, CD117, myeloperoxidase, and lysozyme, with occasional immature eosinophils. Although blood and bone marrow examinations showed no morphologic evidence of leukemia, conventional cytogenetic studies of marrow demonstrated inv(16)(p13q22) in 4 of 20 metaphases; fluorescence in situ hybridization of the bladder neoplasm also showed inv(16). Following chemotherapy, the patient has been in complete remission for 32 months. In our literature review, we identified 7 cases of MS involving bladder, only 3 without evidence of an associated myeloid neoplasm in marrow, none with cytogenetic data. A high index of suspicion is required to establish the diagnosis of MS involving bladder. Cytogenetic analysis is useful for both demonstrating minimal marrow disease and classifying MS in paraffin-embedded tissue sections.     

腮腺滤泡性树突状细胞肉瘤1例及文献复习

目的探讨滤泡性树突状细胞肉瘤的病理诊断及鉴别诊断。方法对1例腮腺滤泡性树突状细胞肉瘤进行HE切片、免疫组化等观察,并复习文献进行讨论。结果镜检肿瘤细胞呈梭形、卵圆形、多边形,胞质淡染,边界不清,核染色质颗粒状并见明显小核仁,可见散在核分裂象,呈片状、束状、编织状、旋涡状排列。较多淋巴细胞浸润及围绕血管形成袖套状结构。肿瘤细胞特异性地表达CD21、CD23、CD35、S-100蛋白、CD68、vim entin、EMA。结论滤泡性树突状细胞肉瘤是极少见的低中度恶性肿瘤,可出现多种组织结构,有一定的特征性,确诊需要免疫组化帮助。应与异位脑膜瘤、异位胸腺瘤、恶性纤维组织细胞瘤、淋巴上皮样癌及指突性树突状细胞肿瘤等相鉴别。     

Imprint cytology of histiocytic sarcoma manifesting as a retroperitoneal mass: A valuable aid for frozen section diagnosis

Histiocytic sarcoma (HS) is a comparatively rare hematolymphoid neoplasm. Differential diagnosis of this entity has generally been proven to be so difficult that extensive immunohistochemical staining is required to confirm its presence. We herein present a case of HS manifesting as a retroperitoneal mass in which imprint cytology (IC) contributed to the diagnosis. A 77‐year‐old man was referred for the evaluation of a colonic tubulovillous polypoid lesion. Preoperative imaging revealed a 3 cm‐sized polypoid lesion in the transverse colon. Incidentally, a retroperitoneal mass of 8 cm in the left para‐aortic region was also detected. Diff–Quik stained IC slides were prepared as an adjunct to intraoperative pathology consultation. The smear exhibited moderate cellularity involving loosely cohesive cell clusters with intervening delicate vasculature. Most of the tumor cells consisted of large single cells with abundant eosinophilic cytoplasm that was vacuolated and foamy. The nuclei were predominantly large and eccentrically located. Mitotic figures were minimal in number and finely granular brown pigments were occasionally observed. A frozen section diagnosis was reported as a malignant neoplasm, and a histologic diagnosis of HS was confirmed by conducting a battery of immunohistochemical stains: negative for pan‐cytokeratin, EMA, CD117, HMB45, Melan A, CD30, PAX5, CD20, S‐100, and CD23 but strong positive for vimentin and CD68. This entity is rarely described in terms of cytopathologic features. This case study highlights how cytopathologists should be aware of HS as a retroperitoneal lesion and should become familiar with cytomorphologic features.     

Epithelioid angiosarcoma of the kidney: a diagnostic dilemma in fine-needle aspiration cytology

Epithelioid angiosarcomas (EAS) of kidney are rare and aggressive tumors with noncharacteristic imaging features that overlap with those of inflammatory conditions and renal cell carcinoma (RCC). We report the fine-needle aspiration (FNA) cytology findings of a case of EAS that involved the left kidney of an 83-year-old male. The smears and cell block sections showed pleomorphic epithelioid cells with ample cytoplasm, eccentric nuclei, occasional cytoplasmic hyaline globules, and rare intracytoplasmic lumina. Immunohistochemical stains performed on cellblock sections showed that the tumor cells were positive for vimentin, CD31, CD34, Factor VIII, and CD10, but showed no staining for cytokeratins AE1/AE3 and 8/18, HMB45, CD45, smooth muscle actin, and S100. The morphological and immunohistochemical distinction between EAS, primary tumors of the kidney, and other epithelioid and rhabdoid neoplasms is discussed.     

Human herpesvirus 8 and iron staining are useful in differentiating Kaposi sarcoma from interstitial granuloma annulare

We studied 20 granuloma annulare (GA) cases (10 interstitial and 10 palisaded) and 19 Kaposi sarcoma (KS) cases (9 "early" and 10 typical). Tissue sections were stained for iron, Hale colloidal iron, human herpesvirus 8 (HHV-8), CD31, CD34, CD68, collagen IV, factor XIIIa, and MIB-1. Iron staining of dermal tissue associated with the lesion was confirmed in all KS cases and no GA cases. Immunohistochemical stains for HHV-8 were positive in all 9 cases of early KS and most cases (9/10) of typical KS. All 20 cases of GA were HHV-8-. CD31, CD34, CD68, factor XIIIa, and MIB-1 were also stained but were difficult to interpret and did not seem specific for GA or KS. Iron staining and immunohistochemical HHV-8 staining in combination were reliable markers for KS compared with interstitial GA. MIB-1 fractions of less than 5% favored a diagnosis of GA, whereas fractions greater than 10% favored a diagnosis of KS. This study provides novel data characterizing iron staining in KS and details the use of iron staining, HHV-8, and MIB-1 to distinguish KS from GA.     

Malignant pleuropulmonary epithelioid hemangioendothelioma – Unusual presentation of an aggressive angiogenic neoplasm

Epithelioid hemangioendothelioma (EHE) of the lung and pleura are rare tumors. Primary pleural EHE are associated with aggressive behavior and poor clinical outcome. Recent advances in EHE include the development of immunohistochemical markers of vascular differentiation, namely Fli-1, and the identification of a specific chromosomal translocation (t(1;3)(p36;q25)). We present a 19 year old male patient with a rapidly progressive malignant neoplasm that presented as a multinodular lung parenchymal process, with associated pleural effusion and thickening. Pathologic examination revealed a pleuropulmonary neoplasm with cytologic features including round to oval epithelioid cells with frequent cytoplasmic vacuoles. Immunohistochemistry confirmed vascular differentiation of tumor cells (CD34, CD31 and Fli-1 positive). While the cytologic features were suggestive of EHE, the aggressive nature of the neoplasm, with disseminated pleuropulmonary involvement, raised the question of whether the neoplasm should be classified as EHE or epithelioid angiosarcoma. Here, we review the clinicopathologic characteristics of pleuropulmonary EHE and the overlap between malignant EHE and angiosarcoma.