低度恶性纤维黏液样肉瘤3例临床病理分析

目的探讨低度恶性纤维黏液样肉瘤(low grade fibromyxoid sarcoma,LGFMS)的临床病理学特征、诊断及鉴别诊断。方法回顾性分析3例LGFMS的临床病理学特征、免疫表型等,并复习相关文献。结果3例患者均为男性,年龄48~61岁,平均51岁,临床以“无痛性软组织肿块”为首要症状,发生部位为臀部、下肢及胸壁。肿物直径较大(6.5~10 cm),均侵犯横纹肌,其中例1伴周围骨质破坏。镜下为丰富的胶原样区与黏液样区相间排列。肿瘤细胞梭形或短梭形,无明显异型性,核分裂象少见。肿瘤细胞呈短束状或涡旋状排列,间质内可见曲线形小血管。肿瘤组织中可见散在的特征性巨菊形团结构。免疫表型:肿瘤细胞MUC-4和vimentin(+),SMA少量(+),Ki-67增殖指数为10%。结论LGFMS是一种具有特殊病理形态、免疫表型及分子遗传学特征的纤维肉瘤亚型,临床过程进展缓慢,局部易复发,熟悉并掌握LGFMS的病理学特点并与其他纤维黏液性肿瘤相鉴别尤为重要。     

消化道低度恶性纤维黏液样肉瘤6例临床病理分析

目的 探讨消化道低度恶性纤维黏液样肉瘤(low-grade fibromyxoid sarcoma, LGFMS)的临床病理学特征和分子学改变。方法 回顾性分析6例消化道LGFMS的临床病理学特征、免疫表型和分子改变。采用免疫组化EnVision两步法检测蛋白表达，FISH法检测FUS基因重排情况，RNA-seq法检测FUS融合基因，并复习相关文献。结果 6例消化道LGFMS中男性4例，女性2例，患者年龄25～49岁，平均年龄和中位年龄分别为38.3岁和40岁。发生于结肠2例，胃、直肠、小肠和肠系膜各1例。5例为手术标本，肿瘤最大径2～15 cm(平均7.9 cm),1例为穿刺活检标本。低倍镜下见肿瘤多位于消化道壁内，由交替性分布的胶原性区域和黏液样区域组成，两区之间有移行。高倍镜下见瘤细胞形态一致，呈短梭形或卵圆形，核深染，染色质均匀细腻，胞质呈淡嗜伊红色。核分裂象罕见，无坏死。瘤细胞呈长束状、交织状、漩涡状或杂乱状排列。1例肿瘤内见巨菊形团结构，其中央为放射状排列的胶原纤维，周围环绕多层瘤细胞。1例含有硬化性上皮样纤维肉瘤样区域。免疫表型：6例瘤细胞均弥漫表达MUC4,1例弱表达E...     

浅表肢端纤维黏液瘤的临床病理特征

目的 探讨浅表肢端纤维黏液瘤(SAF)的临床病理学特点、免疫表型和鉴别诊断.方法 对1例发生于左手中指末端SAF的临床表现、组织形态和免疫学表型进行回顾性分析,并复习文献.结果 患者男,62岁.因左手中指背侧末端肿块伴疼痛就诊,曾有外伤史.术中见肿块近甲床,并深达骨膜.大体观察,肿块周界不清,直径约2 cm,切面呈灰白色,实性,质韧.镜下观察,肿瘤位于真皮层内,略呈分叶状.瘤细胞由梭形至星形纤维母细胞样细胞组成,呈杂乱状分布于黏液样基质内,局部区域可呈条束状或疏松的席纹状排列.黏液样基质内含有丰富的纤细血管,并可见较多散在的肥大细胞.瘤细胞异型性不明显或仅显示轻度的异型性,核分裂象罕见.肿瘤内也未见坏死.免疫组织化学标记显示,梭形和星形细胞表达波形蛋白、CD34和CD99,灶性表达CD10,不表达上皮细胞膜抗原、肌动蛋白、结蛋白和S-100蛋白.结论 SAF好发于成年人指趾末端.熟悉其临床病理特点则有助于与其他发生于指趾的软组织黏液性肿瘤相鉴别.临床上宜将SAF作完整性切除,以预防局部复发.     

低度恶性纤维黏液样肉瘤2例临床病理分析

目的 探讨低度恶性纤维黏液样肉瘤(low-grade fibromyxoid sarcoma,LGFMS)的临床病理学特征.方法 对2例LGFMS的临床资料、病理学形态、免疫表型进行分析.结果 患者年龄分别为31、47岁,平均39岁.肿瘤均位于腹股沟,最大径分别为3.5、6 cm,境界清晰,临床完整切除.镜下肿瘤组织由纤维胶原样区和黏液样区交替组成,细胞形态比较温和,呈梭形或短梭形.2例肿瘤细胞vimentin、α-SMA(+),Ki-67(+<1%),desmin、S-100、CK、EMA、CD34均(-).2例随访至今均未见复发.结论 LGFMS是一种罕见的软组织肿瘤,具有复发和转移潜能,患者需进行长期随访.     

低度恶性纤维黏液样肉瘤临床病理分析

目的:探讨低度恶性纤维黏液样肉瘤(low-grade fibromyxoid sarcoma,LGFMS)的临床病理特征和诊断要点.方法:分析3例LGFMS的临床资料,观察组织学形态、免疫表型及分子病理检测结果,讨论鉴别诊断并复习相关文献.结果:患者均为女性,中位年龄57岁,肿瘤分别位于右侧膝关节前方、右侧乳腺和左侧上颌窦.肿块最大径为2.2～10.0 cm,边界欠清,似有包膜,切面灰白,部分区域呈半透明状,质中有黏液感.镜下见肿瘤组织主要由梭形纤维母细胞样细胞构成,包括两种形态区域,其一为细胞稀疏的胶原样区域;其二为细胞相对较丰富的黏液样区域.肿瘤组织中可见较多弓形血管并伴有血管周玻璃样变性.瘤细胞形态温和,无明显异型性,核分裂象罕见.免疫组织化学染色结果示:vimentin,MUC4,CD99及bcl-2阳性表达,SMA,desmin,S100,CD34,ALK及myogenin阴性表达.发生于右侧乳腺的病例行荧光原位杂交(fluorescent in situ hybridization,FISH)检测,检出FUS基因易位.发生于右侧膝关节和乳腺的2个病例分别随访20个月和51个月,患者均无瘤生存.发生于左侧上颌窦的病例于手术后12个月死亡.结论:LGFMS常见于年轻人,但各年龄段患者均可受累.好发部位为下肢近端和躯干,少见于头颈部和乳腺.LGFMS具有温和的多样性的组织学形态,容易误诊为具有黏液样结构的其他梭形细胞肿瘤.LGFMS具有转移和复发的恶性生物学行为,治疗上需对肿块作完整切除并长期随访观察.     

儿童低度恶性纤维黏液样肉瘤临床病理学分析

目的探讨儿童低度恶性纤维黏液样肉瘤(low grade fibromyxiod sarcoma,LGFMS)的临床病理特征。方法收集2010年1月至2019年1月复旦大学附属儿科医院4例LGFMS,观察其临床、影像学、组织学、免疫组织化学、分子遗传学及预后特征。结果LGFMS男女患者各2例,发病年龄3~13岁(平均年龄9岁);临床表现为缓慢生长的无痛性肿块;典型的形态为黏液样区域和纤维胶原样区域交替性分布,1例局灶区域可见巨菊形团结构;肿瘤细胞表达波形蛋白(4/4)、MUC4(4/4),Ki-67阳性指数5%~20%;荧光原位杂交均可检测到FUS基因的断裂重排;4例均接受手术切除,例2随访71个月后复发。结论儿童LGFMS临床表现不具有特异性,其具有独特的组织学特征,免疫组织化学MUC4阳性表达及FUS基因断裂重排检测有助于其诊断及鉴别诊断。     

四肢躯干低度恶性纤维黏液肉瘤与黏液纤维肉瘤的临床病理比较分析

目的 探讨发生在躯干肢体5例低度恶性的纤维黏液肉瘤(low-grade fibromyxoid sarcoma,LGFMS)和4例黏液纤维肉瘤(myxofibrosarcoma,MFS)的临床病理特征、生物学行为、诊断和鉴别诊断.方法 分析5例LGFMS的临床病理资料、大体形态、组织学特点、免疫组化标记和预后,并与4例MFS相比较.结果 两类肿瘤能够在组织形态学方面进行鉴别,LGFMS由梭形细胞构成,具有黏液区和纤维间质交替分布的特点.肿瘤细胞无异型性,肿瘤组织无坏死.MFS以细长弯曲的薄壁血管和脂母细胞样细胞为特征,伴有丰富的黏液区而没有大面积的实性区,有肿瘤性坏死.两类肿瘤在免疫组化标记、肿瘤位置和患者的年龄方面也有差别.结论 LGFMS是一种罕见肿瘤,临床病理及生物学行为与MFS不同,二者可以通过临床病理特点进行鉴别,LGFMS较之MFS有更好的预后.     

低度恶性纤维黏液样肉瘤1例及文献复习

目的探讨低度恶性纤维黏液样肉瘤(low-grade fibro-myxoid sarcoma,LGFMS)的临床病理学特征。方法对1例LGFMS进行大体、组织病理学和免疫组化染色观察,并复习相关文献。结果眼观:肿瘤大小约14 cm×11 cm×4 cm,边界清楚,无明显包膜,切面灰白色,质硬、韧。镜检:瘤细胞细长梭形或短梭形,富含瘤细胞胶原纤维区和瘤细胞稀少的大量黏液区混合存在,瘤细胞围血管形成旋涡状结构。瘤组织内可见长形或弓状簿壁血管,侵及周围横纹肌组织。免疫组化:瘤细胞表达vimentin和CD99。结论 LGFMS是一种具有局部复发和转移潜能的低度恶性肉瘤。     

伴巨菊形团的玻璃样变梭形细胞肿瘤

伴巨菊形团的玻璃样变梭形细胞肿瘤（hyalinizing spindle cell tumor with giant rosettes,HSCTGR）由Lane等,于1997年首先报道,是一种主要由梭形纤维母细胞样细胞组成的肿瘤,并认为是低度恶性疑难纤维黏液样肉瘤（low-grade fihromyxoid sarcoma,LGFMS）的一种省见变异,截至2003年英文文献有近60例报道,     

腹腔内淋巴结外滤泡树突细胞肉瘤的临床病理学分析

目的探讨腹腔内结外滤泡树突细胞肉瘤的临床病理学特征、免疫表型及与EB病毒感染的相关性。方法分析4例腹腔内结外滤泡树突细胞肉瘤的临床和形态特点,采用CD21、CD23、CD35、波形蛋白、S-100蛋白、上皮细胞膜抗原（EMA）、CD68、CD34、CD117、HLA-DR、CD1a、结蛋白和d-平滑肌肌动蛋白等抗体进行免疫组织化学标记（EnVision法）,采用原位杂交检测EBER。结果患者发病年龄28-63岁（平均42岁）,男性3例,女性1例。临床上表现为腹部不适、腹痛和腹部肿块。影像学检查显示,1例患者同时含有2个病灶,分别位于胃黏膜下和肝左叶,另3例表现为腹腔内肿块,术后显示分别位于阑尾、空肠系膜和大网膜。2例在术前被诊断为胃肠道间质瘤。大体上,肿瘤呈结节状,平均直径为10．8cm,3例肿瘤内可见明显的坏死灶。镜下4例非肝脏性肿瘤均由胖梭形、卵圆形至上皮样细胞组成,可见散在的多核瘤细胞。瘤细胞主要呈席纹状、旋涡状或条束状排列,部分区域呈片状分布。肿瘤内可见散在的淋巴细胞,常围绕血管分布,并与瘤细胞形成双相细胞性形态。2例肿瘤显示明显的异型性,核分裂象易见（包括病理性）。3例肿瘤内可见凝固性坏死。1例肝脏肿瘤由大量的慢性炎性细胞和散在的异形大细胞组成,呈炎性假瘤样。免疫组织化学标记显示,瘤细胞均弥漫强阳性表达CD21、CD23和波形蛋白,部分表达CD35、S-100蛋白、CD68、HLA-DR和EMA,不表达CD34和CD117。2例EBER病毒检测均为阴性。结论发生于腹腔内的结外滤泡树突细胞肉瘤非常少见,熟悉其特征性的病理形态和免疫表型有助于与腹腔内其他类型梭形细胞肿瘤（特别是胃肠道间质瘤）的鉴别诊断。除经典型外,发生于肝脏者可呈炎性假瘤样形态,易被误诊。腹腔内非肝脏性滤泡树突细胞肉瘤与EB病毒感染的关系并不密切。     

Hyalinizing spindle cell tumor with giant rosettes and low-grade fibromyxoid sarcoma: an immunohistochemical and ultrastructural comparative investigation

Hyalinizing spindle cell tumor with giant rosettes (HSCTGR) and low-grade fibromyxoid sarcoma (LGFMS) are 2 variants of fibrosarcoma, which share several clinicopathologic features. This study compares the light microscopic, immunohistochemical, and ultrastructural features of 2 examples of HSCTGR and 3 of LGFMS to determine the degree of overlap of these 2 tumors. HSCTGR were composed of bland spindle cells within hyalinized to myxoid stroma. Scattered throughout the lesions were characteristic rosette-like structures, formed by a central collagenous core surrounded by spindled neoplastic cells. LGFMS consisted of a mixture of fibrous and myxoid areas, composed of fibroblast-like cells arranged in a swirling, whorled growth pattern. Immunohistochemical analysis showed diffuse positivity for vimentin in all cases, while few scattered tumor cells stained for CD57, CD34, factor XIIIA, and actin. The extracellular matrix showed intense positivity for type IV collagen, laminin, and fibronectin, with the exception of myxoid areas of LGFMS and the central core of the giant rosettes in HSCTGR. Ultrastructurally, both tumor types were composed of cells with the features of fibroblasts, embedded in a collagenous stroma with irregular deposits of amorphous basal lamina-like substance. In conclusion, HSCTGR and LGFMS share similar immunophenotypic and ultrastructural features, and together with other fibrosing fibrosarcomas, like sclerosing epithelioid fibrosarcoma, may constitute a subset of fibrosarcomas formed by fibroblasts capable of producing large amounts of basal lamina-like material.     

Low-grade fibromyxoid sarcoma: a clinicopathologic study of 18 cases, including histopathologic relationship with sclerosing epithelioid fibrosarcoma in a subset of cases

Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon tumor with diverse histopathologic features. It has been found to be histopathologically and genetically related to hyalinizing spindle cell tumor with giant rosettes. Lately, sclerosing epithelioid fibrosarcoma (SEF) has been identified as another rare variant of fibrosarcoma. Very few studies have addressed the aspect of its histopathologic relationship with LGFMS. The present study was conducted to critically analyze the clinicopathologic features of a series of LGFMS cases, including identification of cases with histopathologic similarity with SEF. During a 7-year period, 18 LGFMS cases were diagnosed in 9 male and 9 female patients, had ages ranging from 10 to 69 years (median, 32.5 years), and were most commonly identified in the lower extremities (8 cases, or 44.4%). Most cases (16, 88.8%) showed “classic” features of LGFMS with mild (13 cases, or 72.2%) to moderate atypia (5 cases) and nil mitosis (12 cases, or 66.6 %). Variable features included whorling tumor growth pattern, small rosettes, perivascular hyalinization, and amianthoid-like collagen, along with epithelioid differentiation and nuclear pseudoinclusions within tumor cells. Four cases (22.2%) with large collagenous rosettes were diagnosed as hyalinizing spindle cell tumor with giant rosettes. Distinct SEF-like areas were observed in 6 cases (33.3%). On immunohistochemistry, consistent vimentin positively reinforced fibroblastic lineage of the tumor. Therapeutically, all 4 of 7 cases with available follow-up details, which underwent wide excisions, have been free of disease at 5 to 61 months. Eight excisions with unclear margins included 3 cases free of disease (24, 36, and 52 months) and 1 case with recurrence and metastasis. Two cases of marginal excision had tumor recurrences, including 1 case that recurred after 10 years. Low-grade fibromyxoid sarcoma is an uncommon sarcoma with diverse histopathologic features. Histopathologic relationship exists between LGFMS and SEF in a few cases. An LGFMS is optimally managed with surgical wide excision and follow-up.     

Low-grade fibromyxoid sarcoma arising in the big toe

Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor. Reported herein is a case of LGFMS arising in the big toe. The patient was a 58-year-old man who underwent excision of the tumor. The tumor was well-demarcated. Histologically, there were proliferating spindle-shaped tumor cells arranged in a whorled growth pattern, and the stroma showed hyalinized collagen bundles and a myxoid matrix. Nuclear mitotic figures were conspicuous in part. A large rosette-like structure with hyalinized stroma was found, which is characteristic of LGFMS. The differential diagnosis included tumor occurrence in adults; tending to arise in distal extremities; and having bland fibromyxoid histological features, such as fibroma of tendon sheath, low-grade myxofibrosarcoma and acral myxoinflammatory fibroblastic sarcoma. It was not possible to detect the FUS/CREB3L2 and FUS/CREB3L1 fusion genes from the formalin-fixed and paraffin-embedded tissue, although the histological features of the present case were typical of LGFMS. LGFMS may become more common with time, and unique cases may accumulate.     

Hyalinising spindle cell tumour with giant rosettes: report of a case with unusual features including original histological and ultrastructural observations

Hyalinising spindle cell tumour with giant rosettes (HSCTGR) is an uncommon, recently described low-grade sarcoma which shares many histological features with low-grade fibromyxoid sarcoma (LGFMS). We report a case of HSCTGR occurring in the deep soft tissues of the thigh of a 46-year-old woman, that presented as a slowly growing, painless mass. Microscopically the tumour was composed of spindled stromal cells amongst which were scattered so-called collagen rosettes. The distinctive feature of this case was the previously unreported finding of lymphoid cells of T-cell phenotype admixed with fibrohistioctyic cells in the cellular cuff surrounding the collagenous core of the rosettes. The case was further unusual in that it included focal areas of increased cellularity with a mitotic count of up to three per 10 high-power fields. While the latter feature has been associated with increased recurrences and metastases in LGFMS, it is not known whether the significance is similar in HSCTGR. The spindled stromal cells showed ultrastructural features of poorly differentiated fibroblasts, while those at the edges of the rosettes showed features of altered fibroblasts, some with a fibrohistiocytic appearance. These findings support the interpretation that HSCTGR forms part of the spectrum of sarcomas showing fibroblastic differentiation.     

Primary intrathoracic low-grade fibromyxoid sarcoma

Low-grade fibromyxoid sarcoma (LGFMS) is a rare neoplasm commonly affecting young adults and typically arising in the somatic soft tissue of the proximal extremities. Its occurrence within the thoracic cavity is exceedingly rare. We report an LGFMS arising from the epicardial surface of the right side of the heart in a 44-year-old woman. Diagnosis was aided by a strikingly characteristic light microscopic appearance of a bland spindle cell sarcoma containing numerous so-called giant collagen rosettes and supported by immunohistology, evidence of FUS translocation by fluorescence in situ hybridization, and electron microscopy demonstrating a fibroblastic phenotype. Aspiration cytology showed a nonspecific bland spindle cell lesion. Review of the literature uncovered 5 previously reported examples of intrathoracic LGFMS. Low-grade fibromyxoid sarcoma is probably an underrecognized intrathoracic neoplasm and should be considered in the differential diagnosis of spindle cell neoplasms of the mediastinum, pleura, heart, and lungs.     

A case of hyalinizing spindle cell tumor with giant rosettes in the presacral region. Immunohistochemical and ultrastructural study

Hyalinizing spindle cell tumor with giant rosettes is a slowly growing tumor with a risk of local recurrence in case of incomplete surgical excision that could be regarded as a distinctive type of low-grade fibroblastic tumor. We report a case involving the presacral area. This tumor was composed of areas of bland spindle cell proliferation with a fascicular pattern in a fibrous or myxoid stroma, intermixed with giant rosettes consisting of rounded cells surrounding a central collagen core. The tumor expressed vimentin, and, for cells comprising the rosettes, S-100 protein, NSE and CD-57. These latter cells exhibited ultrastructural features of Schwann cells, the tumoral cells of fascicular area exhibiting features of fibroblastic cells. Flow cytometry showed DNA-aneuploidy and a very low S-phase fraction. This tumor appeared to be composed of two cellular components, fibroblastic and Schwann cells, located, at the opposite of neurofibroma, in two distinct areas.     

Epithelioid fibrosarcoma of the ovary

Recently, low-grade fibromyxoid sarcoma/hyalinizing spindle cell tumor with giant rosettes (LGMFS/HSCT) and sclerosing epithelioid fibrosarcoma (SEFS) have come to be recognized as distinctive types of fibrosarcoma. Because their pathological features seem to sometimes overlap, it may be that these tumors belong to a similar entity. We report an aggressive sarcoma with unusual histology arising from the right ovary of a 44-year-old woman. The tumor was 12 cm in size, and there were multiple distant metastases to lung, kidney, stomach and bones. Microscopically, the tumor was composed of broad sheets or variously sized nodules of polygonal epithelioid cells accompanied by hyalinous stroma, resembling SEFS. The hyalinous nodules surrounded by the palisading epithelioid cells, as seen in a rosette of HSCT, were scattered. Between these nodules, spindle cells arranged in fascicles or whorled bundles, mimicking LGMFS, proliferated. Immunohistochemical and ultrastructural analyses revealed fibroblastic differentiation of epithelioid cells and the myofibroblastic nature of the spindle tumor cells. We think the present tumor is a distinctive epithelioid fibrosarcoma with the combined features of SEFS and LGFMS/HSCT, suggesting their intimate relationship.