Intranodal palisaded myofibroblastoma with so-called amianthoid fibers: A report of two cases with a review of the literature

Two cases of intranodal myofibroblastoma, a rare primary spindle cell tumor of the lymph node, are described. The tumors arose in the Inguinal or proximal region of the thigh of one middle-aged and one elderly Japanese male. The tumors were well-demarcated and composed of a fascicular proliferation of spindle cells with focal nuclear palisading and acellular stellate-shaped collagen-rich areas (so-called amianthoid fibers), and were associated with hemorrhagic areas. lmmunohistochemically, the tumor cells were positive for vimentin and muscle actin. Together with ultrastructural findings of intracytoplasmic microfilaments with focal denslties and profiles of welldeveloped, rough endoplasmic reticulum, these features reinforced the conclusion of myofibroblastic or smooth muscle differentiation of the tumor cells. One of the tumors was analyzed by flow cytometry and was shown to be DNA dlploid. The present report provides cllnicopathological findings of the first two Japanese cases of intranodal myofibroblastoma.     

Intranodal palisaded myofibroblastoma of para‐esophageal lymph node: Case report with cytologic and histologic findings

Intranodal palisaded myofibroblastoma is a rare lymph node mesenchymal neoplasm that most commonly arises in inguinal lymph nodes. There is limited data about cytologic features of this tumor and its diagnostic pitfalls. The combination of bland appearing spindle cells, fibrillary matrix, and hemosiderin pigments are the characteristic features of this neoplasm in cytologic specimens.     

栅状肌纤维母细胞瘤3例报道及文献复习

目的：观察栅状肌纤维母细胞瘤的临床病理特征，探索该肿瘤的组织来源及石棉样纤维的性质和来源。方法：对３ 例栅状肌纤维母细胞瘤进行组织形态学和免疫组织化学研究，结合文献对本病的诊断标准、鉴别要点及组织来源进行探讨。结果：栅状肌纤维母细胞瘤的组织学特点为梭形肿瘤细胞呈交叉束状、栅栏状排列，间质内有较多出血、散在的肥大细胞，肿瘤中出现石棉样纤维。免疫组化见肿瘤细胞及石棉样纤维星芒状突起中ａｃｔｉｎ、ｖｉｍｅｎｔｉｎ 呈阳性表达，ｄｅｓｍｉｎ、Ｓ１００ 、ＦａｃｔｏｒⅧ、ｃｙｔｏｋｅｒａｔｉｎ 呈阴性表达。结论：栅状肌纤维母细胞瘤是一种具有独特临床病理特征的肌纤维母细胞瘤，该肿瘤来源于肌纤维母细胞或特殊平滑肌细胞亚型。石棉样纤维中心为血管周围胶原的变性，星芒状纤维为增殖的肌纤维母细胞突出的中间丝和微丝。     

Collagen composition and ultrastructure of the so-called amianthoid fibres in palisaded myofibroblastoma. Ultrastructural and immunohistochemical study.

A very prominent feature of the recently described intranodal palisaded myofibroblastoma is the occurrence of stellate crystalline extracellular deposits known as 'amianthoid fibres', and thought to represent abnormally thick collagen fibrils. We showed at the ultrastructural level that these deposits are composed of fibrils with the periodicity and width typical of normal native collagen. Using antibodies directed against various extracellular components, we have determined that these structures contain type I and III collagens. Our results indicate that the crystalloid deposits in intranodal palisaded myofibroblastoma called 'amianthoid fibres' do not contain giant collagen fibrils widely regarded as characteristic of the morphological concept 'amianthoid' in other locations.     

Intranodal myofibroblastoma presenting in the submandibular region: evidence of a broader clinical and histological spectrum

Intranodal myofibroblastoma is an uncommon benign mesenchymal tumour of lymph nodes which was first described in May 1989. All the cases described to date have presented exclusively in the groin, a feature which has been regarded as distinctive. Two new cases are presented herein, both of which arose in the submandibular region of middle-aged females. Both lesions showed histological features marginally different from the cases originally described, which may reflect their different anatomical location. Immunohistochemical staining revealed positivity for muscle-specific actin (HHF 35), as previously described, and ultrastructural examination in one case confirmed the presence of myofibroblasts. The data presented suggest that this distinctive lesion has a broader clinicopathological spectrum than previously realised.     

Intranodal Myofibroblastoma: Report of a Case

Palisaded myofibroblastoma (hemorrhagic spindle cell tumor) is a recent addition to the group of benign primary spindle cell lesions of lymph nodes. These tumors are characterized histologically by hemorrhage, palisading, and foci of collagen called amianthoid fibers. We report a further typical example with the aim of discussing its differentiation. Tumor cells were positive for smooth-muscle actin and vimentin. The cytoplasm contained moderate numbers of rough endoplasmic reticulum cisternae and some smooth-muscle type myofilaments. Sub-plasmalemmal densities and plasmalemmal caveolae, as well as material interpreted as external lamina, were identified at the cell surface, whereas the fibronexus junctions typical of myofibroblasts were not seen. Immunostaining for type IV collagen was positive. Intranodal myofibroblastomas have largely been considered as myofibroblastic, but the observations presented here raise the alternative possibility of simple smooth-muscle differentiation. The foci of collagen widely referred to as amianthoid fibers contained fibrils mostly of conventional diameter, 50-83 nm. The giant collagen fibrils typical of true amianthoid change were absent. It is suggested that the term amianthoid be used only after ultrastructural confirmation of the presence of giant collagen fibrils.     

Intranodal myofibroblastoma: a case report and review of literature

Intranodal myofibroblastoma is rare benign spindle cell neoplasm of lymph node, first described in 1989, that can be confused with other spindle cell tumor. Immunohistochemical and ultrastructural analysis are essential for a correct diagnosis. We reported a typical case of intranodal myofibroblastoma in a 72-year-old female, which is, to our knowledge, the 64th case described in literature. Myofibroblastic differentiation of the lesion was revealed by immunohistochemical positivity for smooth-muscle actin and vimentin and negativity for desmin and S100 protein. On ultrastructural examination the neoplasm showed the presence of cytoplasmic myofilaments with dense bodies and attachment plaques or hemidesmosome-like structures. We also review the literature in order to delineate the clinical and pathological features of this rare neoplasm.     

Diagnostic clues for FNA diagnosis of intranodal palisaded myofibroblastoma,a rare benign lesion,an introspective case report

Intranodal palisaded myofibroblastoma (IPM) is a benign entity, characterized by intranodal proliferation of cells of myofibroblastic origin. It has five distinct histologic features: compressed remnants of lymphoid tissue at the periphery, spindle cells with nuclear palisading, intralesional hemorrhage, amianthoid fibers, and intracellular and extracellular fuchsinophilic bodies. The spindle cells are SMA and vimentin (IHC) positive and are negative for S 100, and has a low proliferative index. Cytologic diagnosis of this lesion is a diagnostic challenge and has to be differentiated from other stroma rich lesions including schwannoma. The FNA smears were reviewed after histopathology to look for any specific features. This report highlights the variable character of spindle cells, presence of unique “amanthiod fibers” and blood vessel within cell clusters in MGG stained FNA smears, which can be a useful diagnostic clue. This observation is being reported for the first time. Diagn. Cytopathol. 2016;44:317–323. © 2016 Wiley Periodicals, Inc.     

浅表宫颈阴道肌纤维母细胞瘤的临床病理学观察

目的探讨浅表宫颈阴道肌纤维母细胞瘤（superficial cervicovaginal myofibrohlastoma,SCVM）的临床病理学特点、免疫表型、超微结构和鉴别诊断。方法对1例发生于阴道和穹隆部的SCVM进行组织学观察、免疫组化标记和电镜检测。结果患者,63岁,因阴道分泌物增多1个月并扪及有肿物自阴道口突出就诊。妇检于阴道右前壁上方和阴道左上穹隆处可见直径分别为3cm和1．1cm的带蒂肿块。大体上,肿块均呈椭圆形,边界清晰。低倍镜下,肿瘤位于黏膜下,呈卵圆形,与周围组织分界清楚,但无包膜。位于肿瘤浅表或周边区域内的瘤细胞成分相对稀疏,间质呈黏液样或水肿样;位于中心区域内的瘤细胞相对密集,细胞之间可见纤细、致密的胶原纤维。高倍镜下,瘤细胞由形态基本一致、淡嗜伊红染的梭形细胞和星状细胞组成,瘤细胞无明显的异型性,核分裂象罕见（〈2个／50HPF）。在瘤细胞稀疏、问质呈黏液样的区域内,瘤细胞多呈短条束状、网格状、花边状或筛孔状排列,或排列紊乱,偶见多核性细胞;在瘤细胞密集、间质富含胶原纤维的区域内,瘤细胞多呈条柬状或波浪状排列,并与胶原纤维的走向一致。肿瘤内含有散在分布的薄壁血管,间质内可见丰富的肥大细胞,并见少量的慢性炎细胞浸润。免疫组化标记显示,瘤细胞强阳性表达vimentin、desmin、ER和PR,灶性表达CD34,不表达EMA、α-SMA、MSA、hcaldesmon、NF、S-100蛋白、CD57和calretinin等。电镜检测显示瘤细胞部分具肌纤维母细胞分化。结论SCVM是一种起自于女性阴道和宫颈黏膜下浅表基质的良性间叶性肿瘤,其独特的组织学形态提示SCVM可被视为一种新的病种。免疫表型和超微结构均显示瘤细胞具肌纤维母细胞分化。SCVM应注意与同样好发于女性下生殖道的一些间叶性病变相鉴别。     

Myofibroblastoma of the breast showing rare palisaded morphology and uncommon desmin- and CD34-negative immunophenotype: A case report

Myofibroblastoma is a rare benign mesenchymal tumor typically arising in the breast. We report a diagnostically challenging case of myofibroblastoma of the breast showing a rare palisaded morphology and an uncommon desmin- and CD34-negative immunophenotype. A 73-year-old man underwent an excision for an 8 mm-sized breast mass. Histology revealed that the tumor was composed of fascicles of bland spindle cells showing prominent nuclear palisading and Verocay-like bodies. First, schwannoma, malignant peripheral nerve sheath tumor, and synovial sarcoma were suspected given the palisaded morphology. However, none of them was confirmed by immunohistochemical or molecular analyses. Next, a palisaded variant of myofibroblastoma was suspected by the morphology and coexpression of estrogen, progesterone and androgen receptors, BCL2 and CD10 in immunohistochemistry. However, the key diagnostic markers, desmin and CD34, were both negative. Finally, the diagnosis of myofibroblastoma was confirmed by detecting RB1 loss in immunohistochemistry and monoallelic 13q14 deletion (RB1 and FOXO1 loss) by fluorescence in situ hybridization assay. For the correct diagnosis of myofibroblastoma, it is important for pathologists to recognize the wide morphological spectrum, including a palisaded morphology, and the immunophenotypical variations, including desmin- and CD34-negative immunophenotypes, and to employ a comprehensive diagnostic analysis through combined histological, immunohistochemical and molecular evaluations.     

Aspiration cytology of the collagenized variant of mammary myofibroblastoma: a case report with review of the literature

Myofibroblastoma of the breast is a rare benign stromal neoplasm, which occurs primarily in men. Classical myofibroblastoma is a circumscribed, nonencapsulated tumor comprised of bipolar fusiform cells arranged randomly, or in fascicles alternating with broad collagenous bands. Additional histologic variants (the cellular, collagenized, infiltrative, and epitheloid types) have been described. Several case reports describe the cytopathologic features of the classical and cellular variants. We report on a 70-yr-old woman, who presented with a circumscribed mass in her left breast. Aspiration biopsy showed paucicellular smears with singly distributed atypical spindle-shaped cells and rare fragments of collagenized stroma, raising suspicion of a phyllodes tumor. Histologic examination revealed spindle-shaped cells distributed in a diffusely collagenized stroma. Some nuclear atypia was present. To the best of our knowledge, this is the first case reporting the cytologic features of the collagenized variant of myofibroblastoma. Although we believe a specific diagnosis of myofibroblastoma can be rendered in a male based on the typical cytologic and clinical findings in the classical type, the variant forms are difficult to classify accurately and require excision for a definitive diagnosis.     

Fine‐needle aspiration cytology of a mammary myofibroblastoma: A case report on the role of immunohistochemistry and cell block preparations and a review of the literature

Myofibroblastoma (MFB) is a benign tumor of the mammary stroma with predominant myofibroblastic differention. The cytologic reports of MFB are very few in the available literature. From the cytodiagnostic point of view about 21 cases of MFB with cytological evaluation by fine‐needle aspiration cytology (FNAC) have been encountered in the English‐language literature: A 35‐year‐old woman presented with lump in the left breast. FNAC showed mild degree of pleomorphism with occasional groups with fibrous stroma and tumoral cells. A few benign epithelial cell groups were seen. Hematoxylin–eosin‐stained sections of cell block preparation from the aspirate showed fascicles of spindle cells forming whorl structures. Three months later, excision biopsy was performed. The diagnosis was a classic variant of MFB. On immunohistochemical examination, sections were found to be highly positive for vimentin, CD34, and bcl‐ 2. In light of these findings, cell block material was retrospectively reviewed both morphologically and immunhistochemically. The findings of resection and cell block material were found to be very similar. MFB may cause a potential diagnostic pitfall while interpreting FNAC due to its wide differential diagnosis spectrum. We concluded that cytology and cell block findings complement each other. Diagn. Cytopathol. 2016;44:1064–1069. © 2016 Wiley Periodicals, Inc.     

Castleman并发Hodgkin病1例报道及文献复习

目的：探讨以Ｃａｓｔｌｅｍａｎ病组织学特征为主要表现的Ｈｏｄｇｋｉｎ病的病理学特点及两者之间的关系。方法：对１例以Ｃａｓｔｌｅｍａｎ病组织学特征为主要表现的Ｈｏｄｇｋｉｎ病进行了光镜、免疫组织化学及原位分子杂交的观察。结果：淋巴结组织内淋巴滤泡明显增生,淋巴滤光性发中心大小正常或较小,部分滤泡中中心网状细胞增生,小淋巴包 套状排列似洋苞皮样结构,滤泡间及副皮质区见有明显增生的血管,部分血管壁增厚并     

Mammary myofibroblastoma: report of two cases with fine-needle aspiration cytology and review of the cytology literature

Fine-needle aspirates from two histologically, immunohistochemically, and ultrastructurally confirmed mammary myofibroblastomas (MM) of two elderly women revealed abundant, randomly arranged single and clustered benign spindle-shaped mesenchymal cells with scant cytoplasm and elongated or oval nuclei displaying a finely granular chromatin pattern and inconspicuous nucleoli. In one case a few cells showed inconspicuous nuclear grooves. The aspirated tumor cells from the other case stained positively with desmin and CD34 antibodies and negatively with cytokeratin and S-100 protein antibodies, in keeping with an MM. A review of the literature was briefly presented.     

具石棉样胶原纤维的脑膜瘤

目的 探讨脑膜瘤石棉样纤维的本质及其形成机制。方法 应用HE染色、组织化学、免疫组织化学染色及电镜观察l例具石棉样纤维的脑膜瘤的特点。结果 光镜下石棉样纤维为粗细均一的、呈放射状整齐排列的嗜酸性细丝构成的小体。ABPAS和网染小体周围带呈强阳性，中央中间带呈阴性。FN免疫组化染色小体边缘带阳性，中央中间带阴性。电镜下石棉样纤维由平行排列的胶原原纤维组成，与周围肿瘤组织内的胶原纤维有近似的周期和宽度，但原纤维平行排列呈放射状或栅状。结论 本例脑膜瘤，石棉样纤维是一种呈放射状排列的粗大胶原纤维，纤维沉积在球形或半球形的空隙内，小体周围瘤细胞与间质通过小体表面对小体具有均等的吸附力，使其呈放射状排列。     

肉瘤样型间变性大细胞淋巴瘤临床病理特征

目的探讨肉瘤样型间变性大细胞淋巴瘤(sALCL)临床病理特点、免疫表型及分子遗传学特征。方法对1例sALCL的临床、病理组织学、免疫表型及免疫球蛋白重链(IgH)和T细胞受体(TCR)基因克隆性重排情况进行观察并复习相关文献。结果眼观:送检淋巴结1枚,1.5cm×1.0cm×1.0cm,切面呈鱼肉状。镜检:淋巴结基本结构几乎完全被破坏,异型的梭形和上皮样细胞弥漫增生。免疫表型:瘤细胞呈CD30、ALK1、EMA、CD45RO、CD45、TIA1、granzymeB、perforin、CD68(部分)、SMA(梭形成分)阳性。基因重排:TCRβ1克隆性重排。结论sALCL属罕见恶性肿瘤,其形态不典型,易误诊为其他恶性肿瘤,免疫表型和遗传学异常有助于其诊断和鉴别诊断。     

Characteristic cytologic findings of epithelioid hemangioendothelioma: A case report and review of literature

Epithelioid hemangioendothelioma is a rare vascular neoplasm of low-grade malignancy. We observed a case of epithelioid hemangioendothelioma arising in a cervical lymph node. Fine needle aspiration cytology showed several characteristic findings of epithelioid hemangioendothelioma, that is, nuclear inclusion bodies, nuclear grooves, and amorphous material, in addition to physaliform chromatin pattern of a new clue. By reviewing the reports, the prevalence of these is clarified. Complex appearance of these findings is useful in the diagnosis.