Case Of Solitary Fibrous Tumor Research Articles

Renal solitary fibrous tumour: A rare pathological entity.

A solitary fibrous tumour (SFT) is a rare mesenchymal cell neoplasm that can develop at any site. SFT of the kidney is extremely rare. Recently, we had a case of solitary fibrous tumour involving the left kidney in a 71-year-old female patient. The SFT was incidentally found by imaging modalities at the time of a physical workup. Computed tomography and retrograde pyelography showed a 4 × 3.5 × 4-cm nodular mass in the middle poles of the left kidney adjacent to the renal pelvis. A laparoscopic radical resection of the left kidney was performed. The tumour was well-circumscribed and composed of a mixture of spindle cells; microscopically, we found dense collagenous bands. Immunohistochemical studies showed strong reactions with CD34, bcl-2 and CD99. A nuclear positivity with Ki-67 was observed in less than 1% of cells. The tumour was negative for desmin, SMA and CD117. Histopathological and immunohistochemical studies confirmed the diagnosis of a solitary fibrous tumour.

Solitary Fibrous Tumor of the Kidney

Solitary fibrous tumor (SFT) is an unusual spindle cell neoplasm rarely described in the kidney. Usually occurring in the pleura, it has also been described in various extrapleural sites. We report a rare case of SFT of the kidney fortuitously found in a 55-year-old patient. The imaging features are illustrated. The definite diagnosis was made through histological and immunohistochemical study after radical nephrectomy.

Solitary fibrous tumors of the pleura with Doege-Potter syndrome: a case report and three-decade review of the literature

BackgroundNo case of solitary fibrous tumor of the pleura with Doege-Potter syndrome has been reported in China. This study was to report a rare repeatedly recurrent case of solitary fibrous tumor of the pleura with Doege-Potter syndrome diagnosed in China and a three-decade literature review of solitary fibrous tumor of the pleura with Doege-Potter syndrome worldwide.Case presentationA rare case of solitary fibrous tumor of the pleura with Doege-Potter syndrome was diagnosed in 2005 with follow-up to 2011. All medical records were collected and literature of solitary fibrous tumor of the pleura with Doege-Potter syndrome from 1979 to 2011 was obtained through Medline. This typical case, diagnosed and confirmed by histopathologic results, was a 72-year-old Chinese woman who had a complaint of night sweat for a month. A localized mass 12 cm × 11 cm × 8 cm in size was found associated with pleural effusion in her left low chest cavity, and blood tests showed severe hypoglycemia. Removal of the mass solved the hypoglycemia. The case was repeatedly recurrent in April, 2010 and March, 2011 and had no signs of recurrence up to the end of 2011 after surgery. A review of 45 cases of solitary fibrous tumor of the pleura with Doege-Potter syndrome compared and summarized clinical characteristics, treatments, and outcomes by benign and malignant tumor nature.ConclusionsIncidence of solitary fibrous tumor of the pleura with Doege-Potter syndrome is similar between genders. There are no significant differences in clinical characteristics between benign and malignant cases. Surgery is the first effective treatment for solitary fibrous tumor of the pleura with Doege-Potter syndrome and the completeness of the initial resection is the key to preventing recurrence. Routine follow-up examinations are recommended for early detection of recurrence.

A rare case of solitary fibrous tumour of the bladder.

Solitary fibrous tumour of the bladder is a rare mesenchymal neoplasm with a favourable prognosis. Its symptoms are usually secondary to obstructive symptoms rather than hematuria or other findings typical of other bladder neoplasms. We describe a case of solitary fibrous tumour of the bladder and review the literature.

Primary mesenchymal tumors of the pancreas: single-center experience over 16 years.

Primary mesenchymal tumors of the pancreas are extremely rare and no comprehensive study of this class of tumors has been previously performed. Twenty cases of the primary mesenchymal tumors of the pancreas were selected and compared clinicopathologic variables with consecutively resected 500 pancreatic ductal adenocarcinomas. Finally, 20 (0.3%) cases were confirmed as primary mesenchymal tumors. The 14 (70%) cases of benign/borderline tumors included 4 cases of fibromatoses, 2 cases of cavernous hemangiomas, 2 cases of schwannomas, 2 cases of solid and cystic hamartomas, 2 cases of solitary fibrous tumors, 1 case of inflammatory myofibroblastic tumor, and 1 case of angiomyolipoma. The 6 (30%) cases of sarcomas comprised 3 cases of undifferentiated/unclassified sarcomas, 1 case of leiomyosarcoma, 1 case of Ewing sarcoma/primitive neuroectodermal tumor, and 1 case of atypical lipomatous tumor/well-differentiated liposarcoma. When compared with the 500 ductal adenocarcinomas, the 3 surgically resected sarcomas were larger (mean, 5.8 cm vs 3.6 cm; P = 0.02); however, no difference in median survival time was observed between patients with sarcoma (23 months) and patients with ductal adenocarcinoma (16 months). First, primary mesenchymal tumors of the pancreas are extremely rare. Second, several primary mesenchymal tumor types can be observed in the pancreas. Understanding these rare disease entities will help ensure their correct diagnosis.

68Ga DOTATATE PET/CT Imaging of a Solitary Fibrous Tumor of the Nasopharynx

Solitary fibrous tumors (SFTs) are rare group of mesenchymal tumors that occurs predominantly in the pleura. The role of PET/CT imaging in characterizing the SFT is not well reported. Mesenchymal tumors may express somatostatin receptors. We hereby report a rare case of SFT of the nasopharynx showing Ga DOTATATE avidity.

Solitary fibrous tumor of the post-styloid parapharyngeal space

Solitary fibrous tumor (SFT) is a well-known tumor composed of spindle cells found most commonly in the pleura. Recently, accounts of their rare occurrence at other sites, including the head and neck area, have been reported. The parapharyngeal space is a rare location even for head and neck SFTs, and thus, could be confused with a variety of other tumors that can originate in this area. Here, we report a case of SFT originating from the post-styloid parapharyngeal space and discuss the possible differential diagnosis on radiographic findings.

Solitary fibrous tumor arising from pericardium Case report of a rare entity

Solitary fibrous tumor (SFT) is a rare spindle cell neoplasm mainly originated in the pleural cavity. We report here an unusual case of a large SFT arising from the pericardium. A 40 year female with complaints of left sided chest pain was admitted to our hospital with a diagnosis of pericardial mass. CT showed a 11x7 cm mass arising from pericardium showing enhancement and peripheral calcification. Excised mass showed a grey brown well circumscribed nodular mass measuring 8x6x5cm along with attached lobe of lung measuring 6x4x3 cm. Microscopic examination showed a predominant population of monotonous bland looking ovoid to spindle cells arranged in patternless pattern or interlacing bundles with areas of necrosis , hemorrhage and myxoid change, mild nuclear atypia and no mitotic activity. Immunohistochemistry revealed that the tumor cells were positive for CD34, BCL-2, Vimentin and Desmin (focally) and negative for EMA, SMA and Calretinin. Based on histomorphology and immunohistochemistry, the final diagnosis of solitary fibrous tumor was made.

Imaging findings of solitary fibrous tumor in the abdomen and pelvis.

The purpose of this study was to investigate the imaging characteristics of solitary fibrous tumor (SFT) in the abdomen and pelvis. Nine cases of SFT confirmed by surgery and pathology were retrospectively analyzed in terms of computed tomography (CT, eight cases) and magnetic resonance imaging (MRI, one case). SFT were located in the retroperitoneum (4/9), abdominal cavity (1/9), pelvis (4/9). Eight cases were single (8/9) and one case (1/9) with three tumors. The average tumor size of 11 lesions was 9.7cm (4.7-20cm). Nine tumors were round or ovoid, and two lesions were irregular. The CT value of the plain scans ranged from 33 to 43Hounsfield units (HU, mean 37.6HU) in five cases. Arterial-phase CT found solid parts demonstrate avid enhancement (eight cases) and five of them presented with multiple circuitous vessels along the periphery with a CT value of 68-89HU (mean76.6HU). In the venous and delayed phases, enhancement was strengthened progressively. The CT values at venous (eight cases) and delayed phases (five cases) were 108-115 and 112-123HU respectively, with averages of 109.8 and 114.8HU. Patch or nodular no-enhanced areas were observed in eight cases during the enhanced phases. One case showed isointensity on T1-weighted images and high signal intensity on T2-weighted images accompanied by linear or curvilinear hypointense lines. Intense enhancements along with linear no-enhancement areas are seen in the arterial and venous phases. The possibility of SFT should be considered when a single or multiple masses with sharp border, inhomogeneous density or signal are detected, especially, with inhomogeneous intense enhancement in the arterial phase being maintained in the venous and delayed phases.

A Rare Case of Solitary Fibrous Tumor of the Adrenal Gland Detected by 18F-FDG PET/CT

A 33-year old man underwent an F-FDG PET/CT searching for the cause of a fever of unknown origin. F-FDG PET/CT incidentally detected a focal area of markedly increased radiopharmaceutical uptake corresponding to a 2.5-cm nodule in the right adrenal gland. Laboratory data ruled out the presence of a functioning adrenal lesion. All these findings were suggestive of adrenal malignancy. After right adrenalectomy, histology showed a benign solitary fibrous tumor of the adrenal gland. This case highlights that benign solitary fibrous tumor should be considered as possible false-positive F-FDG PET/CT finding for malignancy in evaluating adrenal incidentalomas.

Surgical treatment for recurrent solitary fibrous tumor invading atlas

Solitary fibrous tumor (SFT), a rare neoplasm, usually originates in the pleura. Extrapleural SFTs occasionally occur in the head and neck. In this study, the extirpation of a rare case of recurrent SFT invading the atlas is discussed. Ten years after surgical resection of an SFT in the right parapharyngeal space, the patient returned with a complaint of swelling sensation in the right neck. MRI and CT showed an enhanced lobulated mass invading the right lateral C1 vertebral body and canal and encasing the right vertebral artery. Extirpation of the recurrent tumor with a combined transcervical and midline posterior approach was successful. The surgical margin was negative for cancer and the postoperative course was uneventful. Although an SFT is generally benign, recurrence can occur even after several years, therefore, careful long-term follow-up is essential for early detection. A combined transcervical and midline posterior approach proved useful for resection of the atlas body.

STAT6 Immunohistochemistry Is Helpful in the Diagnosis of Solitary Fibrous Tumors

Solitary fibrous tumor (SFT) is an uncommon fibroblastic neoplasm. Although histologic characteristics and frequent CD34 expression allow for an accurate diagnosis in the majority of SFT cases, a wide histologic spectrum and an occasional unexpected immunophenotype may pose diagnostic challenges. Molecular analyses have discovered that almost all SFTs harbor an NAB2-STAT6 fusion gene, which is considered specific to this tumor type. Recent studies have suggested that STAT6 immunohistochemistry is a reliable surrogate for detection of the fusion gene. Our aim was to validate these findings by examining a large number of SFT cases and a broad array of 30 different types of non-SFT tumors. A total of 49 SFTs with a range of histologic characteristics and 159 benign or malignant tumors that can mimic SFTs were retrieved and stained for STAT6. All 49 SFTs (100%) showed STAT6 expression that was restricted in the nucleus, mostly in a diffuse and strong manner, irrespective of the tumor sites and histologic patterns. The staining was uniform in most cases but was heterogenous in about 20% of the cases in which zonal staining attenuation was observed, likely reflecting variability in fixation or tissue ischemia. In contrast, only 4 non-SFT tumors (2.5%) exhibited weak nuclear STAT6 expression, whereas the remaining 155 cases showed no staining or often weak reactivity in both the cytoplasm and the nucleus. Therefore, nuclear STAT6 immunoreactivity is a highly sensitive and specific marker of SFTs and can be helpful when diagnosis is inconclusive by conventional methods.

STAT6-positive intraorbital papillary tumor: A rare variant of solitary fibrous tumor?

We experienced a peculiar case of orbital mesenchymal tumor in a 22-year-old Japanese woman. The tumor showed a papillary proliferating pattern, but no typical hemangiopericytomatous staghorn vessels. The tumor was composed of round to oval shaped cells with oval nuclei and mild nuclear atypia. Abundant vascular cores were present in the central portion of papillary proliferations of tumor cells. Immunohistochemistry revealed that the tumor cells were positive for CD34 and bcl2. Moreover, they showed positive nuclear signals of STAT6, which have recently been shown to be specific for solitary fibrous tumors. In the literature, only one case of solitary fibrous tumor with papillary and retiform growth pattern has been reported, but the case partially showed the typical staghorn vessel pattern. Although the definite diagnosis is difficult in the settings of the unusual histology and the deficiency of NAB2–STAT6 fusion, it is possible that this STAT6-positive intraorbital papillary tumor is a very rare variant of solitary fibrous tumor.

Solitary fibrous tumor of the soft palate: A report of two cases.

Solitary fibrous tumors (SFTs) are a unique group of mesenchymal neoplasms of fibroblastic or myofibroblastic origin and are extremely rare in the oral cavity. The present study reported two additional cases of SFTs in the soft palate, along with the computed tomography characteristics, which demonstrated well-circumscribed soft tissue lesions with marked and homogenous enhancement. Following wide resection, one of the cases showed certain malignant pathological characteristics, including infiltration of mucinous gland, hypercellularity, nuclear atypia and weak positive staining for S-100. In our experience, SFTs should be considered as a differential diagnosis when a well-circumscribed and solid mass in the soft palate is identified.

Nuclear expression of STAT6 distinguishes solitary fibrous tumor from histologic mimics

Solitary fibrous tumor (SFT) is composed of spindled to ovoid cells in a patternless architecture with prominent stromal collagen and hemangiopericytoma-like vessels. Some tumors show hypercellularity, nuclear atypia, and significant mitotic activity; the latter feature in particular often portends an aggressive clinical course. SFT can sometimes be difficult to distinguish from other benign mesenchymal tumors and sarcomas. The most characteristic (albeit nonspecific) immunohistochemical finding in SFT is CD34 expression. A NAB2–STAT6 gene fusion, resulting in a chimeric protein in which a repressor domain of NGFI-A binding protein 2 (EGR1 binding protein 2) (NAB2) is replaced with a carboxy-terminal transactivation domain from signal transducer and activator of transcription 6, interleukin-4 induced (STAT6), was recently identified as a consistent finding in SFT. However, as these genes are located in close proximity on 12q13, this fusion can only rarely be detected by conventional chromosomal banding or fluorescence in situ hybridization analysis. Nuclear expression of the carboxy terminal part of STAT6 is a consistent finding in SFT of the meninges (so-called ‘meningeal hemangiopericytoma'). We investigated STAT6 expression by immunohistochemistry in SFTs and other soft tissue tumors arising outside the central nervous system to validate the diagnostic utility of this novel marker. Whole-tissue sections of 231 tumors were evaluated, including 60 cases of SFT as well as other benign and malignant mesenchymal neoplasms and sarcomatoid mesotheliomas. Fifty-nine of 60 SFT cases (98%) showed nuclear expression of STAT6, which was usually diffuse and intense. All other tumor types were negative for STAT6, except for three dedifferentiated liposarcomas and one deep fibrous histiocytoma, which showed weak staining. In conclusion, STAT6 is a highly sensitive and almost perfectly specific immunohistochemical marker for SFT and can be helpful to distinguish this tumor type from histologic mimics.

English

This paper reports a rare case of solitary fibrous tumor(SFT) arising independently from the external auditory canal. A 16-year-old female patient presented with mass in left external auditory canal and aural fullness. Physical examination revealed a large papillomatous mass coming out from left external auditory canal. The patient underwent surgical removal of tumor. A light microscopic study showed a spindle-cell proliferation with a collagenous stroma and a staghorn-like vascular pattern. The tumor cells were immune histochemically positive for vimentin. One week after resection aural fullness had resolved. Solitary fibrous tumor is a rare mesenchymal tumor which originates in the pleura or at virtually any site in the soft tissue.It has been observed that 78% to 88% of SFT's are benign and 12% to 22% are malignant.En-bloc resection remains the cornerstone of therapy. Although, several cases of extra pleural SFT have been reported, only one case of external auditory canal SFT has been reported so far. Excision of SFT of the external auditory canal is advisable, especially in the presence of symptoms, and should be preceded by confirmation of non-malignancy by biopsy, if possible.

Solitary fibrous tumor of the lumbar spine: the great mimicker-report of the fifth case.

Solitary fibrous tumor (SFT) is a rare neoplasm occurring in the central nervous system. It rarely occurs in the spine. This paper reports the fifth case of SFT in a 34-year-old female and focusses on differential diagnosis and importance of surgical treatment.

Orbital Solitary Fibrous Tumor: Report of a Three Cases Series

In the current report we present three cases of solitary fibrous tumors of the orbital area that we have seen in a relatively short lapse of time. Most periocular tumors formerly identified as soft tissue hemangiopericytomas, are currently recognized as solitary fibrous tumors, and probably hemangiopericytomas, solitary fibrous tumors, giant cell angiofibromas and fibrous histiocytomas are actually the same tumour, despite some morphologic and immuno labeling variations.

A Case of Solitary Fibrous Tumor in the Nasal Cavity Resected via Endoscopic Surgery

The solitary fibrous tumor (SFT) is a rare neoplastic entity which typically originates from the pleura and other serosal tissues, and infrequently arises in the head and neck region. A 26-year-old female, who complained of nasal obstruction, was referred to us for a tumor in the left nasal cavity. A contrast-enhanced computed tomography scan showed a heterogeneously enhanced mass. The pathological findings of this hemorrhagic tumor on the first biopsy were compatible with a nasal polyp; however, the specimen on rebiopsy revealed a spindle cell neoplasm which was immunohistologically positive for CD34 and bcl-2, leading to the diagnosis of SFT. The tumor was endoscopically resected, the pathologic finding of which was identical to the preoperative diagnosis. The patient showed no evidence of recurrence four years after the operation. Immunohistological staining is essential for the diagnosis of SFT, as HE staining alone is insufficient to dif ferentiate it from other tumors.

頭頸部に発生したsolitary fibrous tumorの4例

Solitary fibrous tumor（SFT）は線維芽細胞類似の紡錘形細胞が膠原線維を伴い増生する比較的まれな間葉系腫瘍で，胸腔内に発生し胸膜由来のものが多い。症例1は79歳女性。気管右側の25mmの腫瘤を摘出しSFTと診断された。症例2は33歳女性。左鼻腔内より生じたSFTに対して歯齦部切開にて腫瘍を切除した。症例3は47歳男性。右下頸部の80mm大の頸部腫瘍を摘出しSFTと診断された。症例4は63歳女性。9歳時より再発を繰り返すSFTが下顎に転移したため，下顎区域切除施行し腫瘍を摘出した。病理組織学的には4例とも紡錘形細胞がpatternless patternをとって密に増生し，CD34（＋），Vimentin（＋）とsolitary fibrous tumorに矛盾しなかった。症例4では2年後に腰椎転移を認めたが，他の症例については再発を認めなかった。