Epithelioid angiomyolipoma of the liver: case report and review of the literature

Hepatic angiomyolipoma is a rare tumor. Here we describe a case and review the literature.     

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。     

肾上皮样血管平滑肌脂肪瘤肺转移1例报告并文献复习

目的：探讨肾上皮样血管平滑肌脂肪瘤病理特点及生物学行为。方法：对1例低热患者行肺肿块穿刺活检,然后行HE染色和免疫组织化学染色。复习肾肿瘤病理切片并进行文献复习。结果：穿刺活检病理分析：密集分布的上皮样细胞,细胞体积大,呈圆形、多边形;异型明显;无血管平滑肌脂肪瘤结构;免疫组织化学：人黑色素瘤蛋白阳性,平滑肌肌动蛋白阳性,上皮膜抗原阴性。病理诊断：左肺上皮样血管平滑肌脂肪瘤;考虑来源于肾。结论：上皮样血管平滑肌脂肪瘤是一种有恶性潜能的间叶性肿瘤,可以发生远处转移。     

Renal epithelioid angiomyolipoma: a case report and literature review

BACKGROUND: Renal epithelioid angiomyolipoma is a recently recognized variant of angiomyolipoma, closely simulating renal cell carcinoma both clinically and histologically. Only a relatively small number of cases of epithelioid angiomyolipoma of the kidney have been reported. AIM: To highlight clinicopathological features of this rare tumour. OBSERVATION: We report herein a new case of renal epithelioid angiomyolipoma in a 38-year-old male with no stigmata of tuberous sclerosis. The tumour was composed of diffuse sheets of epithelioid cells, small numbers of adipocytes and occasional blood vessels. Immunohistochemically, neoplastic cells were immunoreactive for HMB-45, but negative for cytokeratin. The patient showed no evidence of recurrence or metastatic disease one year after radical nephrectomy. CONCLUSIONS: Epithelioid angiomyolipoma may be locally aggressive and can metastasise; therefore, long-term post-operative follow-up is mandatory.     

硬化性上皮样纤维肉瘤临床病理特点及其诊断

目的探讨硬化性上皮样纤维肉瘤(sclerosing epithelioid fibrosarcoma,SEF)的临床病理学特征、诊断及鉴别诊断。方法对1例SEF进行组织学观察和免疫组化标记,同时复习相关文献。结果SEF主要以上皮样细胞伴大量胶原纤维为特征,瘤细胞胞质透亮,似上皮细胞,排列呈条索状,间质中大量胶原纤维发生透明变性,形成硬化性基质。肿瘤细胞vimentin阳性,cytokeratin和actin阴性。结论SEF是一种较为罕见的软组织肿瘤,应注意与一些具有上皮样形态和硬化性间质的肿瘤相鉴别。     

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.     

肾脏不典型血管平滑肌脂肪瘤4例报道并文献复习

目的：探讨肾脏不典型血管平滑肌脂肪瘤（ａｔｙｐｉｃａｌ ａｎｇｉｏｍｙｏｌｉｐｏｍａ,ＡＡＭＬ）的临床病理特征。方法：收集４例曾误诊为肾肉瘤样癌或恶纤组的ＡＡＭＬ行光镜、免疫组化观察,并对其中１例和另３例典型ＡＭＬ作电镜观察。结果：ＡＡＭＬ具有以下的病理特点：①肉眼上切面呈棕褐色,可伴有坏死及出血;②光镜下表现为富细胞,主要由胞浆丰富嗜酸性的单核或多核多形性瘤巨细胞和梭形的肉瘤样细胞及胞浆透明成片     

Uterine angiomyolipoma: case report and review of the literature

Extrarenal angiomyolipomas (AML) have been reported at various anatomical sites, but infrequently in the gynecological region. In the uterus, only a few cases have been described. We describe a uterine angiomyolipoma occurring in a 40-year-old woman without evidence of tuberous sclerosis. The tumor arose on the right wall of the uterine body and was partially cystic, and it was associated with marked degeneration. It was composed of mature adipose tissue, anomalous blood vessels and non-vascular smooth muscle cells. Immunohistochemistry revealed that non- vascular smooth muscle cells were positive for alpha-smooth muscle actin (alpha-SMA), desmin, vimentin, antihuman muscle actin (HHF35) and progesterone receptor (PR), and negative for cytokeratin, antihuman melanoma (HMB45), CD34, S-100 and estrogen receptor (ER). It is of particular interest that non-vascular smooth muscle cells were negative for HMB45, in contrast to renal and other extrarenal AML in which HMB45 immunoreactivity has been demonstrated in these cells.     

Perivascular epithelioid cell tumour (PEComa) of the soft tissue

AIMS: PEComa is a rare tumour developing from perivascular epithelioid cells (PEC) and is characterised by positive immunoreactivity for HMB45. Since PEComas are tumours having both a spindle cell component and an epithelioid and giant cell component, as seen in many sarcomas, as well as having a wide distribution in various organs and soft tissue, we reviewed cases originally diagnosed as sarcomas of the soft tissue in our institution and screened them by immunostaining for HMB45. METHODS: Consecutive soft tissue sarcomas (31 tumours) retrieved from the Surgical Pathology file at our institution for a period of 3 years were submitted for immunostaining for HMB45. Cases with positive HMB45 immunostaining were submitted for further immunostaining for MART1, CD68, S100 protein, cytokeratin AE1/3, EMA, vimentin, MSA and CD117. RESULTS: Of 31 sarcomas, three tumours in the group of 11 malignant fibrous histiocytomas (MFH) and unclassified sarcomas showed positive immunoreactivity for HMB45 and MART1 in 1-25% of tumour cells. The three tumours were located in the lower extremities and measured 8, 11 and 12 cm in diameter. Patient gender male:female was 2:1 and ages were 46, 56 and 60 years. Microscopically, the tumours were composed of a variable proportion of spindled cells, multinucleated cells and epithelioid cells disposed in diffuse sheets or nests. Mitotic figures and necrosis were frequent. The immunoreactivity was diffuse for CD68, focal for AE3 and EMA, negative or focal for MSA and CD117, and negative for S100 and AE1. All three patients developed lymph node or distant metastases and died of the disease within 1-2 years. CONCLUSIONS: PEComa re-screened from the group of high grade sarcomas without definite differentiation range from pleomorphic to monomorphic cytohistopathological features. Immunostaining for HMB45 of unclassified sarcomas is useful for the classification of these tumours. They occur preferentially in the lower extremities and have a high malignant potential when associated with large size, tumoural necrosis and high mitotic activity.     

Primary perivascular epithelioid cell tumor in the rectum: A case report and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare collection of tumors arising in a wide array of anatomic locations. It is characterized by the presence of a peculiar population of myomelanocytic marker-positive perivascular epithelioid cells, and is commonly detected in the uterus. The colorectal area is an uncommon site for primary PEComa. In this study, we describe a 17-year-old patient presenting with a rectal polyp. Histologically, the tumor consisted of sheets of round to polygonal epithelioid cells with clear and granular cytoplasm, and a prominent capillary network. Some of the tumor cells were positive for Fontana-Masson staining. Immunohistochemically, the tumor cells were positive for HMB-45, and were negative for cytokeratin, vimentin, S-100 protein, actin, desmin, EMA, CD34, and c-kit. After finding melanosomes or premelanosomes at the ultrastructural level, the diagnosis of PEComa was made. Although PEComa arising within the intestinal tract is unusual and clinically unexpected, PEComa should be considered in the differential diagnosis of rectal polypoid lesions.     

Renal epithelioid angiomyolipoma: a study of six cases and a meta-analytic study. Development of criteria for screening the entity with prognostic significance

Aims:  Renal epithelioid angiomyolipoma (EAML) is only described in case reports or in multi-institutional small series. The aim was to report cases seen at our institution and to perform a meta-analysis based on a literature review.
Methods and results:  Six EAML cases seen at our institution were reviewed and a meta-analysis performed using cases retrieved from a literature review. There were a total of 69 cases for review. The male:female ratio was 1:3. In the absence of areas of typical AML, useful features in distinguishing EAML from epithelial renal neoplasms include: extreme degree of cytological atypia, histiocytoid appearance, presence of melanocytic pigments, solid architecture with the absence of frequent areas of alveolar pattern, tubulo-papillary formation and scarring. A fatal outcome, distant or lymph node metastasis, venous invasion and local recurrence were considered as adverse events and occurred in 40% of cases over a period of follow-up of 3–60 months (mean 22.5 ± 18 months). Tumours with an unfavourable outcome showing marked cytological atypia and extensive tumour necrosis were larger (135 ± 43 mm) than those with a favourable outcome (79 ± 50 mm) ( P  < 0.002), and predominantly occurred in men.
Conclusions:  Renal neoplasms with certain unusual features should be investigated immunohistochemically to rule out the possibility of EAML. The frequency of adverse outcome is lower in EAML than in renal cell carcinoma.     

肝脏血管平滑肌脂肪瘤9例临床病理分析

目的探讨肝脏血管平滑肌脂肪瘤(hepatic angiomyolipoma,HAML)的临床病理特点、诊断及鉴别诊断。方法对9例HAML进行临床病理学观察与免疫组化标记及复习有关文献。结果 9例HAML年龄28～56岁,平均44.2岁,均无结节硬化症。术前影像诊断多数为肝癌。眼观:肿瘤直径1.2～14 cm。肝左叶4例、肝尾状叶3例和肝右叶2例。肿瘤境界清楚,无包膜,质地脆、易碎,可见出血、坏死。镜检:瘤组织由上皮样细胞、平滑肌样细胞、脂肪组织和厚壁血管组成。上皮样细胞体积大或巨大,呈多边形,胞质丰富,嗜酸性或空泡状,核仁明显,可见核内包涵体,偶见多核巨细胞。平滑肌样细胞呈梭形,9例中有4例几乎缺如脂肪组织。瘤细胞弥漫性或巢团状排列。瘤组织出血、坏死明显,呈浸润性边缘。免疫组化标记:瘤细胞HMB-45及Melan-A阳性,SMA和vimentin散在阳性,CK、EMA、AFP均阴性。结论 HAML是一种罕见的间叶组织源性肿瘤,多见于女性,组织学上以单一方向分化的大上皮样细胞为主,瘤细胞较为特异的表达HMB-45及Melan-A。免疫组化标记可与其它肝脏肿瘤鉴别。     

肢端黏液样炎性纤维母细胞肉瘤2例及文献复习

目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记，并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块，术后局部复发。镜检：病变呈多结节状，边界不清；黏液样基质中见数量不等的各类炎细胞浸润，散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型：肿瘤细胞Vim弥漫阳性，CD68和CD34灶性阳性，CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长，术后易局部复发，是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出，而特征性的瘤细胞稀疏，应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。     

软组织网状神经束膜瘤1例报道并文献复习

目的 探讨软组织网状神经束膜瘤的临床病理特点和鉴别诊断。方法 对1例网状神经束膜瘤进行光镜、免疫组化和电镜观察。结果 肿瘤位于左尺骨远端软组织。长而纤细的肿瘤细胞突起网状、格子样、吻合状生长，排列于黏液水肿性、纤维性和胶原化的背景中，细胞纺锤状，胞质弱嗜酸性，核星形，无核分裂象。免疫表型：肿瘤细胞EMA和Vim阳性。电镜：肿瘤细胞可见长形的纤细的胞质突起，突起上有较多的吞饮小泡。结论网状神经束膜瘤是软组织神经束膜瘤的富有特征性的亚型，预后良好，诊断主要依靠常规病理、免疫组化和超微结构的综合观察。     

Primary adrenal gland epithelioid sarcoma: A case report and literature review

Epithelioid sarcoma is a malignant mesenchymal neoplasm with morphologic and immunophenotypic epithelioid differentiation, which rarely arises in solid organs. We report a case of primary epithelioid sarcoma in the adrenal gland of a 31‐year‐old female. The patient initially presented with nausea and rectal bleeding, and subsequent imaging studies revealed a 4.4 cm left adrenal gland mass and left retroperitoneal lymphadenopathy. Clinical and radiological studies did not reveal tumor elsewhere in the patient. Histologic features were those of epithelioid sarcoma, proximal type with cohesive clusters of epithelioid tumor cells harboring frequent mitoses, and areas of necrosis. Immunohistochemical stains showed strong, diffuse expression of epithelial markers (pancytokeratin), and CD34 and Fli‐1. Partial and focal positive staining of CK7 was also noted. Nuclear expression of SMARCB1 (INI‐1) protein was lost. ERG was negative in this case. We believe that this is the second‐case report of a primary adrenal gland epithelioid sarcoma. Fli‐1 positivity was seen in our case, and ERG was negative as shown in some recent publications regarding epithelioid sarcomas.     

肾脏上皮样型血管平滑肌脂肪瘤临床病理分析

目的 探讨肾脏上皮样型血管平滑肌脂肪瘤(EAML)的临床病理特点及诊断与鉴别诊断.方法 通过对3例EAML临床病理学观察与免疫组化标记及复习有关文献,讨论其组织学特征及临床生物学行为.结果 3例年龄分别为28、40和32岁,均有腰痛病史,其中1例伴有肉眼血尿,均无结节硬化症.眼观:肿瘤位于肾脏,直径大小分别为6 cm、8 cm和3 cm.3例境界清楚,例2伴囊性变.肿瘤无包膜,2例出血、坏死明显,质脆或韧.镜检:瘤细胞体积大或巨大,呈多边形,胞质丰富,嗜酸性或空泡状,核仁明显,可见核内包涵体,多核巨细胞散在其中.瘤细胞弥漫性或巢团状排列.2例瘤组织出血、坏死明显,呈浸润性边缘.3例未见典型AML图像.免疫组化染色显示瘤细胞HMB-45阳性,SMA和vimentin散在性阳性,CK、EMA和CD10均阴性.结论 EAML是一种单一方向分化的,含有大上皮样细胞的肿瘤,瘤细胞较为特异的表达HMB-45.辅以免疫组化可以与其它肾脏肿瘤相鉴别.     

Perivascular epithelioid cell tumor (PEComa) of soft tissue: case report with ultrastructural study

A perivascular epithelioid cell tumor (PEComa) arising in the abdominal wall of a 44-year-old female is described. The lesion was a well-circumscribed but unencapsulated, rubbery, subcutaneous mass measuring 3.5 x 3.5 x 3.0 cm which was removed by simple excision. It was characterized by a nest- or sheet-like arrangement of round to polygonal cells with round nuclei and abundant clear to slightly eosinophilic cytoplasm containing glycogen. There was mild to moderate nuclear pleomorphism with mitotic activity of 6 per 10 high power fields. A short fascicular proliferation of the tumor cells was observed focally. The stroma contained abundant small vascular channels with hyalinization. Immunohistochemically, the tumor cells were strongly positive for vimentin, epithelial membrane antigen, alpha-smooth muscle actin, and HMB45. Ultrastructural examination showed poorly differentiated mesenchymal tumor cells without premelanosomes. There was local recurrence 6 years after excision. Pathologists and clinicians should be aware of the existence of PEComa in soft tissue and should differentiate it from other similar lesions.     

Primary alveolar soft part sarcoma of the uterine cervix: a case report and literature review

Alveolar soft part sarcoma (ASPS) is a tumor of unknown histogenesis, composed of large, epithelioid cells with eosinophilic cytoplasm, having an alveolar pattern. Primary ASPS of uterine cervix is very rare. In this report, we present a 21-aged-old female with primary ASPS in the uterine cervix and discuss the clinicopathological characteristics, immunophenotype, molecular genetic feature and differential diagnosis of ASPS of cervix.     

Small-cell extraskeletal osteosarcoma: case report and literature review

Small-cell extraskeletal osteosarcoma is extremely rare and consists of sheets of small round cells with variable amounts of osteoid. This tumor is often difficult to diagnose when tissue samples do not include recognizable osteoid. Only four cases have been reported in English and none in Chinese. We report a typical case of small-cell extraskeletal osteosarcoma occurring in the left leg of a 40-year-old female. Laboratory results were within normal limits. Magnetic resonance imaging demonstrated a soft tissue mass measuring 36 mm × 18 mm in the medial lateral aspect of left limb. The initial histological findings led to a misdiagnosis because the first fine-needle biopsy was randomized and incomplete. However, an open surgical specimen showed recognizable osteoid, which enabled us to make a definitive diagnosis. We also present clinical, radiologic and pathologic features of this case.     

Cutaneous angiomyolipoma: a case report and literature review

Angiomyolipoma is a lesion usually observed in the kidney of patients with tuberous sclerosis. Extrarenal sites are very unusual with sporadic cases in internal organ, soft tissue and skin (fifteen cases have been described in this site). Herein we describe an adding case located on the ear in 58-year-old man reviewing the pertinent literature. The main diagnostic differential criteria are also discussed.