Extrapleural Solitary Fibrous Tumor Research Articles

Extrapleural Solitary Fibrous Tumor: A Clinicopathologic Study of 19 Cases

This study reports a series of 19 extrapleural solitary fibrous tumors. The patients included 6 men and 13 women with age ranging from 27 to 86 years. Three patients showed local recurrence. In 2 tumors, a diagnosis of malignancy was made. All of the tumors were strongly positive for CD34, and 3 of them expressed high levels of progesterone receptor. Solitary fibrous tumors are fairly rare, occurring in many parts of the body, and their behavior is unpredictable.

Hemangiopericytoma and antiangiogenic therapy: clinical benefit of antiangiogenic therapy (sorafenib and sunitinib) in relapsed Malignant Haemangioperyctoma /Solitary Fibrous Tumour

Soft tissue sarcomas are a highly heterogeneous group of tumors. Recently, different molecular abnormalities were identified and in some cases corresponding molecular targeted therapies led to significant clinical benefits. Malignant tumors of blood vessels are classified as sarcomas and are uncommon. They encompass angiosarcoma, hemangioendotheliomas, and hemangiopericytomas. The term hemangiopericytoma (HMP) was coined in 1942 by Stout and Murray for soft tissue tumours thought to originate from cell encircling blood vessels (pericytes)[1]. Over the years the concept of HMP has gradually evolved. It was namely shown that this term has been used for a wide variety of benign and malignant soft tissue tumours which share common morphologic features but correspond to different entities. It is now obvious that some conventional HMP correspond in fact to the spectrum of solitary fibrous tumour (SFT). SFT of the soft tissue (or extrapleural SFT) have an unpredictable behaviour, 10 to 15 % of them showing an aggressive evolution with either local recurrences and/or metastases. SFT located in the mediastinum, peritoneum, retroperitoneum and pelvis tend to be more aggressive than those in other locations. The most common sites of metastasis are the lung, bone, and liver. There is no standard treatment for patients with advanced disease with the exception of anthracyclins largely used in first chemotherapy line. Here, we describe a patient with a hemangioperictoma who achieved a partial response while on sorafenib therapy, and a second case with the same clinical outcome while on sunitinib. First patient was a 59 year-old female was referred to our center for a multi-relapsed hemangiopericytoma. The tumor was diagnosed in 1982 as a pre-sacral hemangiopericytoma and surgery was performed. The patient experienced multiple relapses: lung metastases in 1994 and pancreatic metastases in 1996 were completely resected. In 2000, she relapsed in the lung for the third time and first-line chemotherapy was administered with an anthracyclin-based regimen (cisplatin, epirubicin and ifosfamide). After 6 cycles, the CT-scan showed stable disease and surgery was performed. In 2003, due to further pulmonary progression, the patient was included in a phase II with trabectedin (Yondelis®) but therapy was discontinued because of hepatic toxicity. Invest New Drugs (2010) 28:199–202 DOI 10.1007/s10637-009-9249-1

Solitary Fibrous Tumor of the Larynx

True mesenchymal, non-cartilaginous neoplasms of the larynx are rare. Extrapleural solitary fibrous tumor (SFT) is a localized neoplasm characterized by proliferation of thin-walled vessels and collagen-producing cells and is considered within the "hemangiopericytoma-solitary fibrous tumor" spectrum. SFT primary in the larynx is exceptional. Case report set in a comparison with other cases reported in the English literature (MEDLINE 1966 to 2007). A 49-year old white male presented with difficulty breathing, progressive over the past 2 years. He denied dysphagia and weight loss. Past medical history was significant for asthma. He denied cigarette smoking or alcohol abuse. There were no cervical deformities on physical exam. Fiberoptic laryngoscopy was performed upon stabilization of respiratory function. A smooth, round, submucosal mass measuring 2.3 cm in greatest diameter arising from the inferior surface of left true vocal cord was causing near total obstruction of the endolaryngeal space. The mass was excised. The surface mucosa was intact and unremarkable. A cellular, spindle cell neoplasm was arranged in loose fascicles, associated with heavy collagen fiber deposition. The collagen was wiry and heavy. Cells were bland with cytoplasmic extensions. The nuclei were vesicular to hyperchromatic and elongated with inconspicuous nucleoli. Vessels were prominent and delicate, with patulous spaces. Mitotic figures were easily identified, but atypical forms were not present. The cells were strongly and diffusely immunoreactive with CD34 and bcl-2, while non-reactive with cytokeratin, EMA, actin, ALK-1, S100, desmin, and CD117. These findings confirmed a diagnosis of extraplural solitary fibrous tumor. Without further disease, the patient is alive without evidence of disease, 12 months after surgery. The characteristic histologic pattern of solitary fibrous tumor can be noted in extrapulmonary locations. Development in the larynx is uncommon, but the tumor presents as a polypoid mass with characteristic histologic and immunophenotypic features. Conservative local excision is the treatment of choice to yield an excellent prognosis.

Solitary fibrous tumor of the male breast: a case report and review of the literature

Extrapleural solitary fibrous tumors are very rare and occasionally they appear in extraserosal soft tissues or parenchymatous organs. In such cases the right preoperative diagnosis is often difficult and challenging, because both radiological and cytological examinations are not exhaustive. For these reasons, surgical excision is frequently the only way to reach the correct diagnosis and to achieve definitive treatment. A few cases of solitary fibrous tumors have been also described in the breast. Although rare, this lesion opens difficulties in preoperative diagnosis entering in differential diagnosis with other benign lesions as well as with breast cancer. In this article we describe a case of a solitary fibrous tumor of the breast in a 49-year-old man. Problems related to differential diagnosis and the possible pitfalls that can be encountered in the diagnostic iter of such rare tumor are discussed.

Clinicopathological and immunohistochemical study of extrapleural and pleural solitary fibrous tumors: A special emphasis on the comparison between ordinary tumors and their malignant variant

Solitary fibrous tumors (SFTs) are rare spindle cell tumors that usually arise in the pleura, although they also occur in extrapleural sites. SFTs usually have a favorable clinical course; however, a small number of metastasizing cases have been reported. We evaluated the detailed clinicopathological findings of 20 extrapleural and 16 pleural SFTs. Among them, 6 cases of the histologically malignant variant (4 extrapleural and 2 pleural tumors) were identified. According to the follow-up data, none of the cases, including the 6 malignant tumors, developed metastases in this series. There were no significant differences in the histologic findings between the extrapleural and pleural SFTs. Tumor necrosis was frequently associated with the malignant variant. Immunohistochemically, malignant SFTs revealed more frequent p53 expression (4/6) compared with ordinary SFTs (2/30) (P=0.0027). The MIB-1 labeling index (LI) was significantly higher in malignant SFTs (mean 13.48) than in ordinary SFTs (mean 7.27) (P=0.0023). Our results indicate that tumor necrosis, p53 expression and a high MIB-1 LI are additional parameters of the malignant variant of SFTs, although they do not necessarily have predictive value for biological behavior. Further studies are required to find reliable molecular biomarkers for predicting the clinical outcome of patients with this unique tumor.

Maggot therapy following orbital exenteration

Orbital exenteration is a radical surgery reserved for the treatment of locally invasive or potentially life-threatening orbital tumours.1 Complications occur after 20–25% of exenterations and include tissue necrosis (6%) and...

Solitary fibrous tumor of the thigh with epithelioid features: a case report

BackgroundExtrapleural Solitary Fibrous tumors (SFTs) have been increasingly reported. The retroperitoneum, deep soft tissues of proximal extremities, abdominal cavity, trunk, head and neck are the most common extraserosal locations reported. Microscopically they show a wide range of morphological features, and so the differential diagnosis is extensive. Immunohistochemically, they commonly express CD34, vimentin, bcl-2 and CD99. Epithelial membrane antigen (EMA) and smooth muscle actin (SMA) may occasionally be expressed. Epithelioid morphology in extrapleural SFT has only very occasionally been described (five cases reported), some of them with biphasic pattern and others with malignant characteristics.Case presentationA SFT of the thigh with epithelioid areas in a 63 year old woman is reported. Microscopically the tumor showed areas hypo and hipercellular. At the periphery of the hipercellular areas there were nodules composed of epithelioid cells. Immunohistochemically both the spindle and epithelioid cells were positive for CD34, vimentin, bcl-2 and CD99. Epithelial, neural and muscular markers were negative. Molecular study was done and ruled out a synovial sarcoma.ConclusionTen cases of SFT of the thigh have been reported but to our knowledge this is the first case with epithelioid morphology affecting the extremities. Identification of this pattern of SFT is of importance, to avoid misdiagnosis with other more aggressive conditions in soft tissue.

Extrapleural solitary fibrous tumor: report of a case

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×4.0cm,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。

Solitary Fibrous Tumor of the Orbit With Epithelioid Features

Extrapleural solitary fibrous tumors have often been confused with other mesenchymal tumors, such as hemangiopericytoma, fibrous histiocytoma, fibrous meningioma, and leiomyoma, because of morphologic similarity and underrecognition, especially if some unusual features are present. Recently, epithelioid solitary fibrous tumor has been reported in the mediastinum. We report a case of solitary fibrous tumor of the orbit with biphasic architecture, including spindle cell and epithelioid components. Both components demonstrated immunohistochemical features of a solitary fibrous tumor. A background of scattered vessels was present. No evidence of significant nuclear atypia or mitotic activity was noted. In this report, we discuss the differential diagnosis of solitary fibrous tumor with unusual epithelioid features. Extrapleural solitary fibrous tumor should be included in the differential diagnosis of tumors of the orbit with a spindle cell appearance even in the presence of some epithelioid morphology.

Benign Fibrous Tumors and Tumorlike Lesions of the Mesentery: Radiologic-Pathologic Correlation

Mesenteric fibromatosis, sclerosing mesenteritis, inflammatory pseudotumor, and extrapleural solitary fibrous tumor constitute a loosely associated group of benign fibrous tumors and tumorlike lesions of the mesentery. These lesions are linked histologically by the presence of fibroblasts or fibrosis and anatomically by their location within the mesentery. Although rare, and distinctly different in pathogenesis and biologic behavior, these fibrous lesions have pathologic and radiologic features that overlap with one another and with more common neoplastic and nonneoplastic lesions of the mesentery. Mesenteric fibromatosis is a locally aggressive, benign proliferative process that may occur sporadically or in association with familial adenomatous polyposis. It most frequently manifests as a focal mesenteric mass and may simulate lymphoma, metastatic disease, or a soft-tissue sarcoma. Sclerosing mesenteritis is a rare idiopathic disorder that most commonly produces a stellate mass within the mesentery and should be differentiated from metastatic disease, specifically metastatic carcinoid, because it frequently responds to conservative or medical management. Inflammatory pseudotumor (inflammatory myofibroblastic tumor) is a benign, chronic inflammatory disorder of unknown cause that manifests as a solid mesenteric mass, indistinguishable from malignancy. Extrapleural solitary fibrous tumor is a tumor of submesothelial origin that is identical to the solitary fibrous tumor of the pleura. When located in the mesentery or peritoneal cavity, extrapleural solitary fibrous tumor has an imaging pattern that must be differentiated from metastatic disease, soft-tissue sarcomas, and other benign and malignant neoplasms of the mesentery and peritoneum. Knowledge of this group of benign fibrous tumors and tumorlike lesions of the mesentery is important in the preoperative evaluation of a mesenteric mass.

Ultrastructural spectrum of solitary fibrous tumor: a unique perivascular tumor with alternative lines of differentiation

Eight tumors diagnosed as solitary fibrous tumor (SFT) of the oral cavity were studied. Histologic spectrum was entirely comparable with the extrapleural SFT of other sites. One tumor had glomus tumor-like foci. Immunohistochemical results confirmed most of the previous observations, indicating characteristic expression of vimentin, CD34, bcl-2, and CD99. Factor XIIIa and alpha-smooth muscle actin were less commonly reactive and a very few cells were faintly positive for factor VIII-related antigen and Ulex europaeus agglutinin 1. All were essentially negative for S-100 protein, desmin, CD31, and CD68. In stark contrast to the conclusive immunoprofile, ultrastructural investigation of six tumors demonstrated considerable cellular heterogeneity. Other than fibroblasts, perivascular undifferentiated cells and pericytes predominated, but endothelial cells were regularly present. There was a distinctive proliferation of pericytic cells in four tumors, one of which had glomoid foci of myopericytes. The extreme increase in number of Weibel-Palade bodies occurred in voluminous capillary endothelium. Occasional single and clustered cells with consistent features of endothelium showed intracytoplasmic lumen formation. Such composite cells constituted an integral segment of richly vascularized SFT. Myofibroblastic form smooth muscle differentiation was present in only a minority of cells. From phenotypic analysis by electron microscopy, SFT may originate from a unique, perivascular multipotent mesenchyme sharing with its lineage with pericytes, fibroblasts, and infrequently, endothelium. Consequently, morphological features of SFT may become diversely varied by whether predominantly constituent cells are undifferentiated, pericytic or fibroblastic in nature.

Unusual Solitary Fibrous Tumors in the Central Nervous System: A Report of Two Cases

Solitary fibrous tumors (SFTs) are uncommon, and most are found in the pleura. Extrapleural SFTs are rare and have been found in the lung, pericardium, mediastinum, soft tissue of any site, and upper respiratory tract. SFTs of the central nervous system (CNS) are very rare. The biologic features are unknown and remain poorly understood from a clinical standpoint. Most neurosurgeons do not believe that SFTs can present as primary CNS neoplasms. Most SFTs are clinically benign and indolent, and recurrences after surgical excision are scarce. Because malignant transformation or metastasis has been reported, all SFTs should be treated as having malignant potential. Long-term follow-up is recommended. We report two cases, so that surgeons may recognize that this is an entity different from other spindle-cell CNS tumors.

Solitary Fibrous Tumor in the Occipitocervical Region: A Case Report

Case report of a solitary fibrous tumor in the occipitocervical region. To describe a rare clinical entity and successful management in a patient with solitary fibrous tumor in the occipitocervical region. Solitary fibrous tumor is a rare spindle cell neoplasm of adults that arises most commonly in the pleura. Recently, this tumor has been reported in a number of other sites. However, its occurrence in the occipitocervical region is rare. The patient presented with a painless mass in the left posterior neck. Resection of the tumor was performed. Histopathological study revealed features of a solitary fibrous tumor. Clinical follow-up review for 2.5 years shows no evidence of recurrence or metastasis. A case of extrapleural solitary fibrous tumor in the occipitocervical region was reported. Solitary fibrous tumor should be considered in the differential diagnosis in a tumoral mass of this region.

Extrapleural Solitary fibrous tumor of the oral cavity: proliferation markers, tumor suppressor gene expression, and ultrastructural features

Background Extrapleural solitary fibrous tumors (ESFT) were previously classified as hemangiopericytomas (HPCs). With the current WHO classification, HPCs have been incorporated within ESFTs. A myopericytic category includes tumors with pericytic differentiation. Objective Proliferation markers, tumor suppressor gene expression, and ultrastructural features were evaluated with cellular oral ESFTs. Case reports Two females (53 and 52 years old) presented with recurrent oral masses (1 cm and 1.8 cm) involving the anterior facial gingiva and buccal mucosa. Pathology These cellular tumors were composed of a bland plump spindle cell proliferation embedded in a vascular background. The cells were arranged in a storiform pattern. The adjacent soft tissues were infiltrated by tumor with extension to the margins. Tumor cells were diffusely positive for CD34, Bcl-2 and MCM-7, moderately to focally positive for CD99, mildly positive for Mib-1, and focally positive for p53. Smooth muscle actin, muscle-specific actin, and S100 protein were negative. Electron microscopy revealed bland spindle cells with occasional areas of extracellular collagen precipitation. Glycocalyx material coated the cell surfaces. Attachment plaques and smooth muscle differentiation were lacking. Dermatofibrosarcoma protuberans [t(17;22), COL1A1-PDGFB] and pericytic tumor [t(7;12), GLI-ACTB] translocations were not detected by RT-PCR. Conclusion With these cellular oral ESFTs, proliferation markers (Bcl-2, MCM-7) were expressed diffusely in a high proportion of cells, and p53 also was identified focally. Morphology alone does not predict which ESFTs have aggressive or metastatic potential. Complete excision of ESFTs with close clinical follow-up is the recommended treatment.

A solitary fibrous tumor in the external auditory meatus

We herein describe a rare case of a spindle-cell neoplasm arising in the external auditory canal. A 38-year-old man presented with a progressive swelling of the entrance of left external auditory meatus. The patient underwent a surgical removal of the tumor. A light microscopic study showed a spindle-cell proliferation with a collagenous stroma and a staghorn-like vascular pattern. The tumor cells were immunohistochemically positive for vimentin and CD34. The tumor was thereafter diagnosed to be a solitary fibrous tumor (SFT). SFTs most commonly occur in the pleura and are supposed to originate from submesothelial connective tissue. Although, several cases of extrapleural SFT have been reported, no SFT arising in the entrance of left external auditory canal have ever been reported in the literature. As a basically benign tumor, it occasionally relapses or metastasizes after excision, and therefore a careful follow up is necessary.

Steroid hormone receptor in pleural solitary fibrous tumours and CD34+ progenitor stromal cells.

Solitary fibrous tumours (SFT), originally described in the pleura, were subsequently recognized in numerous extrapleural sites. This suggests that a common stem cell, present in various organs and tissues, may be at the origin of SFT and that specific factors may be involved in the proliferation of such cells. Recently it has been described that steroid hormone receptors, progesterone receptors in particular, are expressed by extrapleural SFT. In addition, progesterone may participate as growth factor in many CD34(+) stromal neoplasms, which express low levels of the hormone receptors. The present study analysed the expression of androgen (AR), oestrogen (ER) and progesterone (PR) receptors in a series of 32 pleural SFT, 10 mesotheliomas and in reactive tissue of chronic pleuritis. ER and AR were never expressed by SFT or by chronic pleuritis, whereas PR were demonstrated in 2/16 "large" (>8 cm) and in 6/16 "small" (< or =8 cm) pleural SFT (all expressing CD34, bcl-2 and CD99). PR(+) SFT had a significantly higher proliferative activity (p = 0.04) (Ki-67 mean value 6.5%) and lower p27(kip1) (mean value 51.5%) expression than the PR(-) cases (Ki-67 mean value 3.81% and p27(kip1) mean value 57.86%). One of the cases expressing a high level of PR (80%) recurred 1 year after first surgery and the recurrence was PR(+) as well, but with a lower percentage of nuclear receptor expression (12%). In addition, in chronically inflamed subserosal tissue, a subpopulation of CD34(+) endothelial and interstitial dendritic cells was identified, which also expressed PR. These findings suggest that the CD34(+) submesothelial interstitial dendritic cells, activated during reactive processes, may be the stem cells that give rise to SFT, and that progesterone might participate in the growth of SFT through modulation of its specific receptors.

Extrapleural solitary fibrous tumor: clinicopathologic study of 17 cases and molecular analysis of the p53 pathway.

Solitary fibrous tumor (SFT) occurring at various extrapleural sites is sometimes difficult to diagnose because of its histologic variability. Although a solitary fibrous tumor is usually a slow-growing tumor with favorable prognosis, a small number of malignant cases have been reported. In the present study, we examined the clinical behavior, histologic, immunohistochemical and molecular features of 17 cases of extrapleural SFT. Four tumors were located in the pelvic cavity, two in the nasal cavity, two were confined to the pulmonary parenchyma, and there was one each in the meninges, kidney, mediastinum, retroperitoneum, temporal region, neck, groin, buttock and thigh. Histologically, all the tumors were characterized by the presence of areas consisting of a proliferation of bland spindle cells with variable amounts of thick, often hyalinized or keloid-like intercellular collagen bundles. Highly cellular areas were observed in three tumors, frequent mitoses in two, and cellular pleomorphism and tumor necrosis in one each. All 17 tumors showed immunoreactivity to CD34 and 15 (88%) to bcl-2 protein. The labeling indices of p53, mdm2 protein and Ki-67 were generally low. PCR-SSCP and a subsequent sequence analysis of the p53 gene disclosed point mutation at codon 161 in exon 5 in one of the 13 cases analyzed. According to follow-up information, none of the patients had developed local recurrence or distant metastasis. Our results suggest that most extrapleural SFTs behave in a benign fashion even in a higher histologic grade group, and it is difficult to predict their clinical outcome. Complete surgical excision in order to obtain clear margins and long-term follow-up is advisable for patients with an extrapleural SFT.

Solitary fibrous tumor of the lower urogenital tract: A report of five cases involving the seminal vesicles, urinary bladder, and prostate

Solitary fibrous tumor (SFT) is not as site-restricted as once believed. Initially described as a tumor of the pleura, SFT is now recognized at various extrathoracic sites. We report 5 cases of extrapleural SFT involving the male lower urogenital tract. The tumors involved the seminal vesicles (2 cases), urinary bladder (2 cases), and the prostate (1 case). The patients with bladder tumors were asymptomatic. The patients with seminal vesicle involvement presented with hematuria or groin pain. The patient with prostate involvement presented with urinary retention. The prostate tumor was large, and it could not be completely excised because of its extensive spread beyond the prostate into the pelvis. The other 4 tumors were completely excised, and none has recurred during limited follow-up. By histological criteria, 4 of the tumors were benign, and 1 was malignant. Even though the classic histological features of SFT were well developed in each case, all 5 tumors were initially misdiagnosed, including 3 benign tumors that were misclassified as sarcomas. These 5 cases confirm the male lower genitourinary tract as yet another site of origin for SFTs, challenge the notion that extrapleural SFTs invariably are benign, and draw attention to the problem of recognizing SFTs when they arise in unexpected sites.

Bcl-2 EXPRESSION IN PLEURAL AND EXTRAPLEURAL SOLITARY FIBROUS TUMOURS

This study evaluated the immunoreactivity for bcl-2, a molecule involved in the control of programmed cell death, in cases of pleural (14) and extrapleural (2) solitary fibrous tumour (SFT), malignant mesotheliomas of different histological types, and a variety of extrapleural CD34-positive and CD34-negative spindle-cell tumours. In all SFTs, strong and diffuse immunostaining was demonstrated with anti-bel-2 antibody, sharply contrasting with the complete lack of staining observed in all mesotheliomas. The specificity of immunodetection of bcl-2 in SFT was confirmed by immunoblot analysis, showing a band consistent with the bcl-2 protein. At extrapleural locations, strong bcl-2 immunoreactivity was observed in Schwannoma (2/3 cases), synovial sarcoma (4/4 cases), and all cases of CD34-positive gastrointestinal stromal tumour (GIST; 10/10 cases). Most sarcomas were bcl-2-negative. Lack of bcl-2 expression was demonstrated in tumours which can pose problems in the differential diagnosis of SFT and can exhibit haemangiopericytoma-like features, including haemangiopericytoma (3 cases), dermatofibrosarcoma protuberans (16 cases), and deep-seated fibrous histiocytoma (3 cases). The constitutive expression of bcl-2 in SFT widens the spectrum of available markers for these tumours, providing a useful adjunct to their differential diagnosis in difficult cases at pleural and extrapleural sites, and contributing to the understanding of their histogenesis and molecular pathogenesis.