Myxoid solitary fibrous tumor: a study of seven cases with emphasis on differential diagnosis.

Focal myxoid change is a well-recognized feature of solitary fibrous tumor (SFT), but to date, predominantly myxoid examples of SFT have not been reported. We describe seven cases of SFT in which stromal myxoid change affected 50% or more of the tumor examined, thus obscuring typical diagnostic features. Patients ranged in age from 35 to 68 years old (median, 45 yr), with an equal sex distribution. Tumor locations included pleura, orbit, and periparotid subcutaneous tissue, as well as four cases in deep soft tissue (two in the abdominal wall and one each in the chest wall and thigh). Myxoid areas were identified grossly in four cases. Histologically, the lesions were composed of bland spindle cells disposed haphazardly or with a lacy or reticulated appearance in a myxoid, richly vascularized stroma These myxoid areas were punctuated by small cellular aggregates in four cases, and areas showing diagnostic features of SFT were present in five of seven primary excision specimens. Atypical features suggestive of malignancy were not present in any of the cases. Immunohistochemically, all of the seven cases stained positively for CD34 and CD99 (013), and all were negative for smooth muscle actin, desmin, S-100 protein, epithelial membrane antigen, and pan-keratin. There were no recurrences or metastases reported in four patients with limited follow-up (median duration, 19 mo). Recognition of this uncommon morphologic subset of SFT is important because of possible confusion, particularly in small biopsy specimens, with a variety of myxoid spindle cell neoplasms with different biologic potential. These include low-grade fibromyxoid sarcoma, myxoid synovial sarcoma, malignant peripheral nerve sheath tumor, low-grade myxofibrosarcoma, myxoid liposarcoma, myxoid spindle cell lipoma, myxoid neurofibroma, and so-called "hemangiopericytoma."     

Spindle cell rhabdomyosarcoma of the tongue in an infant: a case report with emphasis on differential diagnosis of childhood spindle cell lesions

Malignant tumors are extremely uncommon in infants, specifically in the head and neck region. We present a three-day-old infant with a large, polypoid, soft tissue mass arising from the floor of the mouth. Histologically, this neoplasm consisted of hypercellular and myxoid areas. A mixture of poorly oriented, small, undifferentiated, hyperchromatic, and round to elongate spindle cells was seen. A high degree of striated muscle differentiation was present, along with areas marked by a herringbone pattern, as well as hemangiopericytic vessels and rare mitosis. Immunohistochemical examinations revealed strong nuclear staining for myogenin and diffuse cytoplasmic staining for desmin and muscle-specific actin (HHF-35). The tumor did not stain for S-100. Based on histologic results and immunostains, this lesion was diagnosed as spindle cell rhabdomyosarcoma. This type of lesion involving the tongue is rarely seen in females, neither in association with a herringbone pattern nor with hemangiopericytic vessels. Furthermore, rare benign and malignant spindle lesions, such as cellular fibromatosis, fetal rhabdomyoma, infantile hemangiopericytoma, infantile rhabdomyofibrosarcoma, and infantile fibrosarcoma, should be in the differential diagnosis and excluded.     

Fat-forming solitary fibrous tumor of the kidney: a case report and literature review

Fat-forming solitary fibrous tumor (SFT) is a rare soft tissue tumor. Herein, we reported a 30-year-old woman was found to have a solid mass measuring 60×45 mm in the right kidney on an abdominal computed tomography scan. The tumor was well-circumscribed and composed of cellular nodules with the classic SFT admixed with clusters and lobules of mature adipocytes. Immunohistochemistry staining showed that the tumor cells were diffusely and strongly positive for CD34 and Bcl-2, focally and weakly positive for CD99 and EMA. Mature adipocytes were positive for S-100 protein. Ki-67 expression was found in approximately 2% of tumor cells. However, tumor cells were negative for cytokeratin, S-100 protein, HMB-45, Melan-A, SMA, and CD117. We made the pathological diagnosis of fat-forming SFT of the right kidney. The differential diagnosis includes angiomyolipoma, liposarcoma, spindle cell lipoma, sarcomatoid renal cell carcinoma, synovial sarcoma, and gastrointestinal stromal tumor. The patient was alive and well without evidence of recurrence or metastasis at 19 months after tumor resection.     

盆腔囊性孤立性纤维瘤一例

患者女,47岁.因发现下腹部肿块2年于2007年9月19日收入院.体检:患者一般情况良好,妇科检查发现宫体增大如孕50 d大小,左附件区触及15 cm×10 cm×10 cm包块.盆腔彩超提示:左附件区多房囊性占位(考虑卵巢囊腺瘤);子宫多发性平滑肌瘤.     

胸膜外孤立性纤维性肿瘤

例1男,68岁。进行性排尿困难4个月余,于2004年12月12日入院。入院检查会阴部可触及分叶状肿块12 cm×10 cm×5 cm,质硬且固定;术中发现肿块来源于前列腺。病理检查:分叶、结节状组织11．5 cm×10．0 cm×4．0 cm,部分似有包膜,部分已切开,切面鱼肉状,质嫩。显微镜下肿瘤境界清,有较厚的纤维性包膜,肿瘤由富细胞区和细胞稀疏区组成。富细胞区肿瘤细胞呈束状或成簇状的小圆形、卵圆形细胞,部分区杂乱无章(图1)。瘤细胞胞质少,核染色质均匀,核仁不明显,无核分裂象,部分区肿瘤血管丰富;细胞稀疏区含多量胶原纤维。免疫组织化学示:波形蛋白、CD34、Bcl-2均(+,图2,3),CD99(±),肌动蛋白、S- 100、神经微丝(NF)、结蛋白、平滑肌肌动蛋白(SMA)、细胞角蛋白(CK)、CD117均(-)。病理诊断:胸膜外孤立性纤维性肿瘤。     

Primary solitary fibrous tumor of the bronchus: a case report

Solitary fibrous tumors are ubiquitous tumors of fibroblastic type and may be found at any location, but primary solitary fibrous tumors of the bronchus were rarely reported. Here, we reported the case of a 46-year-old woman whose main stem bronchus was partly occluded by a 1.0×0.8×0.7 cm endobronchial mass. The mass was completely resected with lung preservation. The tumor was well circumscribed and consisted of a mixture of bland spindle cells and dense collagen bands. Immunohistochemical staining showed that tumor cells were positive for CD34, bcl-2 and vimentin, but negative for S-100, SMA and cytokeratin AE1/AE3. The tumor was diagnosed as a solitary fibrous tumor of the bronchus, which has been rarely reported to date.     

Hepatic solitary fibrous tumor: report of a rare case

Solitary fibrous tumor (SFT) of the liver is an extremely rare neoplasm of mesenchymal origin. In the English literature, less than 40 cases of SFTs of the liver have been reported. The present case concerns a 34-year-old female who presented to us with complaint of dyspepsia. On examination, there was hepatomegaly. On ultrasound examination, an SOL in the liver was detected. Large tumor measuring 14.5 × 10 × 8 cm was resected. Microscopic evaluation of the tumor showed a well-circumscribed, low to moderately cellular tumor demonstrating spindle- and fibroblast-like cells within the collagenous stroma. Immunohistochemistry revealed diffuse strong cytoplasmic immunopositivity of CD34, Bcl2, and vimentin. A diagnosis of a benign SFT was given. The patient remained well 4 years after surgery. SFT is a rare mesenchymal neoplasm that occasionally involves the liver in adult patients. Most SFTs are benign, but some may have malignant histological features. With less than 40 reported cases in the literature, little can be said regarding its natural history or the benefits of adjuvant radio chemotherapy. Complete surgical resection remains the cornerstone of its treatment.     

肾恶性孤立性纤维性肿瘤1例报道及文献复习

目的 探讨肾脏恶性孤立性纤维性肿瘤的临床病理特征、鉴别诊断及治疗和预后.方法 报道1例肾恶性孤立性纤维性肿瘤的临床病理资料并复习文献.结果 患者男性,56岁.临床主要表现为乏力、出汗、心慌、气短1年,以低血糖原因待查入院.CT示左肾上方及左肾前下方见3个类圆形软组织密度影,与肾分界不清,大小分别为9 cm×8 cm×7 cm、7 cm×7cm×7 cm和4 cm×4 cm ×4 cm.增强后边缘轻度强化,中心不均匀强化.临床、CT检查考虑为左.肾癌.行左肾癌根治术.眼观:左肾上、下极分别见一肿块,切面灰白色,部分区见有坏死,与肾界限不清.镜检:肿瘤由短梭形或卵圆形细胞组成,排列成束状、旋涡状或不规则状.部分区域血管丰富,细胞密集呈血管外皮瘤样结构;部分区域细胞稀疏伴纤维化、黏液变性.肿瘤超过60%的区域内(尤其是肾下极肿块)瘤细胞丰富密集,有异型性,核分裂象多见(>4个/10 HPF),边缘呈浸润性生长,部分区可见出血坏死.免疫表型:肿瘤细胞vimentin、CD34弥漫阳性,CD99、bcl-2阳性,Ki-67增殖指数>20%.病理诊断:左肾恶性孤立性纤维性肿瘤(低度恶性).术后随访24个月情况良好.结论 肾恶性孤立性纤维性肿瘤非常罕见,确诊主要依靠病理形态学及免疫组织化学标记,并应与肾的其他梭形细胞肿瘤进行鉴别.治疗以手术完全切除为主,并注意长期随访.     

Brain-invasive solitary fibrous tumor of the meninges: report of a case

Solitary fibrous tumor is a mesenchymal neoplasm that most commonly arises in the pleura, but also in multiple extrapleural sites including, rarely, the meninges. Immunohistochemical findings facilitate its differentiation from other spindle cell lesions such as fibrous meningioma. Although the great majority of extrapleural solitary fibrous tumors behave in a benign fashion, only rare examples of brain-invasive tumors have been documented. We present a case of a brain-invasive solitary fibrous tumor arising in the meninges of a 40-year-old woman. The tumor was marked by focally prominent hypercellularity, moderate nuclear pleomorphism, and increased mitotic activity. Focal infiltration into the underlying brain parenchyma was observed. The tumor was CD34 positive and EMA negative.     

Sinonasal glomangiopericytoma: case report with emphasis on the differential diagnosis

Glomangiopericytoma (sinonasal-type hemangiopericytoma) is an uncommon sinonasal neoplasm with a perivascular myoid phenotype. This tumor differs from conventional soft tissue hemangiopericytoma in location, biologic behavior, and histologic features. The proposed cell of origin is a modified perivascular glomuslike myoid cell. Glomangiopericytoma is an indolent tumor that tends to arise in the sinonasal tract of older adults and has a low malignant potential with excellent prognosis after surgical resection. Histologically, this lesion is composed of a diffuse, subepithelial proliferation of bland, uniform, closely packed spindled cells growing in a variety of patterns. A distinctive vascular network composed of variably sized vascular channels, the smaller of which demonstrate perivascular hyalinization, is often present. We report the case of a 48-year-old woman with epistaxis and nasal obstruction who was diagnosed with glomangiopericytoma and discuss the histologic differential diagnosis.     

原发性甲状腺及肾脏多发癌伴肾脏孤立性纤维性肿瘤一例

患者女,35岁.因"左髋部疼痛1年,加剧3个月"于2008年4月入院.患者于2007年3月不慎扭伤后出现左髋部疼痛,左腹股沟处有轻压痛,伴轻微跛行,未重视.2007年12月自觉左髋部疼痛加重,在当地医院行X线检查,左髋臼上方见鹅蛋大小骨质缺损.边缘欠光整,遂行左髂骨肿瘤活检.病理经外院会诊意见为:左髂骨转移性神经内分泌癌,癌组织中度分化,富于血窦,形成多个脉管和腺泡样结构,倾向甲状腺滤泡癌.后行PET/CT检查结果提示左髂骨恶性肿瘤及右侧甲状腺腺瘤可能性.随后患者在当地医院行3次"羟基喜树碱、足叶乙甙及顺铂(HEP方案)联合重组人血管内皮抑制素(恩度)"化疗.     

Malignant solitary fibrous tumor of the kidney: report of a case and comprehensive review of the literature

Renal solitary fibrous tumors (SFTs) have been reported infrequently. We report a 76-year-old man with a left renal mass that had previously been shown radiographically to be stable, but was now growing. Grossly, the mass measured 12 cm, was poorly circumscribed, and invaded beyond the renal capsule. Approximately 10% of the neoplasm consisted of haphazardly arranged spindle cells admixed with dense collagenous bands, which is typical of benign SFT. However, the remainder of the mass was composed of pleomorphic, spindled sarcoma cells with frequent mitoses and foci of necrosis. Immunohistochemically, we observed CD34 labeling in the benign SFT component with loss of expression in the sarcomatous component, focal labeling for Bcl-2 protein in both areas, and absence of labeling for cytokeratin, renal cell carcinoma marker, S100 protein, CD117, and muscle markers in both areas. To our knowledge, this is the first reported case of malignant renal SFT, likely representing transformation from a histologically documented benign SFT component.     

Malignant solitary fibrous tumor of breast: a rare case report

Solitary fibrous tumor (SFT) is rare mesenchymal neoplasm that has been originally and most often documented in the pleura. Recently, the ubiquitous nature of the SFT has been recognized with reports of involvement of numerous sites all over the body such as: upper respiratory tract, somatic tissue, mediastinum, head, and neck. Less than 10 cases SFT of breast have been reported. Herein, we presented a 52-year-old Asian female with SFT of breast, this tumor showed predominant malignant features. To our knowledge, SFT of breast with such malignant evidence is extremely rare.     

Ovarian spindle cell lesions: a review with emphasis on recent developments and differential diagnosis

Ovarian lesions composed of spindle cells comprise a heterogeneous group; most are neoplastic but several non-neoplastic conditions are also composed of spindle cells. This review discusses the main differential diagnoses of an ovarian spindle cell lesion, especially concentrating on the recent literature. The majority of ovarian spindle cell lesions fall into the broad category of fibromatous neoplasms whereas others in the sex cord-stromal group may also be composed of spindle cells, including thecomas, granulosa, and Sertoli-Leydig cell tumors and rarer neoplasms, such as sclerosing stromal tumor and signet-ring stromal tumor. In the recent past there have been several major contributions on various aspects of ovarian spindle cell lesions, including cellular and mitotically active cellular fibromatous lesions, smooth muscle neoplasms, and metastatic gastrointestinal stromal tumors. Other mesenchymal or epithelial tumors and mixed epithelial and mesenchymal neoplasms may also enter into the differential diagnosis of an ovarian spindle cell lesion. Several non-neoplastic lesions may be composed of spindle cells, including massive edema, ovarian fibromatosis, stromal hyperplasia, and stromal hyperthecosis. Morphology remains the mainstay in diagnosis but immunohistochemistry may be invaluable in certain circumstances, one example being the identification of a metastatic gastrointestinal stromal tumor within the ovary.     

Malignant solitary fibrous tumor of the pleura: report of a case with cytogenetic analysis

The majority of solitary fibrous tumors (SFTs) of the pleura are benign, but 10-30% locally recur or metastasize. Pathogenic factors relevant to the determinism of their biological properties are largely unknown. Cytogenetic data on SFTs of the pleura are sparse. We report herein a case of a malignant SFT of the pleura where successful karyotyping was obtained from the primary and recurrent tumors. The initial karyotype showed two abnormal clones: 48, XY; +8; +8; del(9)(q22; q32) [19] and 46, XY, t(1;16)(q25;p12) [7]. Culture of the recurrent tumor yielded one clone identical to the dominant clone of the initial karyotype. Demonstration of a recurrent abnormal karyotype largely supports its relevance to the malignant clone and suggests a role of supernumerary chromosome(s) 8 in the determinism of malignant behavior in SFT.     

Synchronous primary triple carcinoma of thyroid and kidney accompanied by solitary fibrous tumor of the kidney: a unique case report

Thyroid cancers coexisted with kidney cancer in a patient is an unusual event. Here, we described a case of 35-year-old woman with synchronous occurrence of primary papillary carcinoma and follicular carcinoma of the thyroid, accompanied by renal cell carcinoma and solitary fibrous tumor of the kidney, which has not been reported in literature to our best knowledge. Its clinical and pathological features, as well as the possible pathogenic factors were discussed.     

Paratesticular solitary fibrous tumor: a case report and review of literature

Solitary fibrous tumor (SFT) is a rare spindle cell neoplasm that usually arising from the pleura, but has been reported in diverse extrapleural sites. Urogenital localization is rare, and only several cases of paratesticular SFT have been reported. In the present report, we present the case of a 61-year-old male suffering from a paratesticular SFT. A surgical excision of the lesion was performed. The tumor was well circumscribed and consisted of a mixture of bland spindle cells and dense collagen bands. Immunohistochemical studies showed positive reactivity for CD34, CD99 and vimentin, but stained negative for CD117, S100, SMA, HMB45, Desmin and CD68. All these clinicopathologic features are suggestive of the diagnosis of paratesticular SFT.     

Giant solitary fibrous tumor of the diaphragm: a case report and review of literature

A young gentleman presented with difficulty in breathing. Computed tomography (CT) scan showed a huge mass located between the heart and stomach, which might have rooted in the diaphragm. Magnetic resonance imaging (MRI) with enhanced three dimensional construction showed a lobulated, heterogeneous soft tissue mass with short T1 weighted imaging signal and flake long T2-weighted imaging (T2WI). Tumor-enhanced scanning demonstrated heterogeneous contrast enhancement. The preliminary diagnosis was intra-abdominal huge mass and considering sarcoma. Resection was conducted where the base of the tumor was located in the diaphragm oppressing the left liver lobe and heart. The base of the tumor, together with partial surrounding of the diaphragm, pericardium base, and the left lateral hepatic segment, was resected. The defect in the diaphragm and pericardium was repaired by patching, and thoracic close drainage and abdominal drainage were placed following the surgical operation. The pathological report showed giant solitary fibrous tumor (SFT). This case report may provide a reference resource for the diagnosis and treatment of SFT located in the diaphragm.     

双肺转移性脑膜孤立性纤维性肿瘤/血管外皮细胞瘤一例

孤立性纤维性肿瘤/血管外皮细胞瘤(SFT/HPC)占原发脑膜肿瘤的0.5%,最大特点是容易复发和转移。肺部作为全身肿瘤最易转移器官,对于肺穿刺活检病理诊断存在极大的难度。作者收集1例双肺转移性脑膜SFT/HPC患者资料,分析其临床病理学特征,为肺部转移性肿瘤诊断及鉴别诊断提供依据。