Pleural solitary fibrous tumor from diaphragm, being suspected of liver invasion; report of a case

We report a case of solitary fibrous tumor (SFT) from diaphragmatic pleura. A 71-year-old female was admitted to our hospital because of an abnormal shadow on chest X-ray. A preoperative imaging study revealed a mass on her right diaphragm. At thoracoscopic exploration, the tumor was found to originate from diaphragm and was suspected of liver invasion. The conversion to open thoracotomy was introduced to perform appropriate surgical procedure. Pathological examination revealed proliferation of spindle cells and collagen fibers. Immuno-histochemical findings showed positive immunostaining for cell differentiation (CD) 34 and vimentin. The tumor was diagnosed as SFT with malignant potential.     

Solitary fibrous tumors of the pleura: clinicopathological and immunohistochemical examination

The purpose of this work was to study clinical and biological characteristics of solitary fibrous tumor (SFT) of the pleura. We reviewed the clinicopathological and immunohistochemical features of 12 patients who underwent surgical resection for SFT. Ten cases were histologically defined as benign; two were found to be malignant. CD34 negativity and strong expression of p53 could be observed in a patient with fatal outcome. Ki-67 expression was increased in malignant cases, as compared with benign. We also found that Bcl-2 expression inversely correlated with a tumor diameter. As the development of malignant SFT might be associated with these molecular statuses, immunohistochemical staining should be performed in all cases to identify the biological characteristics of the tumor.     

Solitary fibrous tumor of the orbit. Case report and review of the literature.

BACKGROUND: Solitary fibrous tumor (SFT), which usually presents in the pleura and is thought to be mesothelial in nature, has been recently discovered in extrapleural sites, including the orbit. Presently ultrastructural studies show absence of epithelial-mesothelial features, and reactivity of the tumor cells to CD34 antigen on immunohistochemical analysis suggests the mesenchymal origin of such tumors. CASE DESCRIPTION: A 40-year-old woman had a 4-year history of progressive swelling of her right upper lid and a slow-growing palpable mass of the orbit. CT and MR imaging showed a well circumscribed, nonenhanced extraconal mass with mild erosion of the right orbital roof. The tumor was totally excised. Histological examination disclosed a spindle-cell tumor in a dense fibrous tissue. Immunohistochemistry showed positive staining for vimentin and CD34. We review the clinical, diagnostic, and surgical features of 22 orbital SFTs including the present case. CONCLUSIONS: Orbital SFT generally pursues a slow, indolent, and nonaggressive course, reaches a size up to 4.5 cm, and can be cured by a single excision. It must be immunohistochemically differentiated from other spindle-cell tumors of the orbit.     

Intrapulmonary Solitary Fibrous Tumor Diagnosed by Immunohistochemical and Genetic Approaches: Report of a Case

Although solitary fibrous tumors (SFTs) of the pleura are not uncommon, intrapulmonary SFTs are extremely rare. A 72-year-old woman was admitted to our hospital for an investigation of an enlarging intrapulmonary tumor. Because a definitive diagnosis could not be readily established, a pulmonary wedge resection under video-assisted thoracic surgery was performed. Grossly, the tumor was white, well circumscribed, and separate from the pleural surface. Histologically, it consisted of spindle cells proliferating in a vague fascicular pattern, with many dilated capillaries, and intermingled glandular components. These findings suggested a differential diagnosis that included SFT and nonchondromatous pulmonary hamartoma. On immunohistochemical analysis, the spindle cells showed a strong positive reaction to the CD34 antigen. Interphase fluorescent in situ hybridization revealed an absence of HMGA-1 and -2 translocations. These results supported a diagnosis of SFT. A genetic approach may therefore be useful in the differentiation of SFT from nonchondromatous hamartoma.     

Solitary fibrous tumor of the liver with CD 34 positivity and hypoglycemia

We report a new case of solitary fibrous tumor (SFT) of the liver, an extremely rare neoplasm. Including the present case no more than ten cases are reported in the English-language literature. To date there is no definite proof of the origin of this tumor. Both mesothelial and fibroblas-tic genesis has been postulated. The monoclonal antibody CD 34 has recently been used for the characterization of SFT. SFT would appear to be histogenetically related to a CD 34 — positive fibroblastic stem cell. A 61-year-old woman was admitted to our department with epigastric and right hypochondriac pain, weight loss, and hypoglycemia. Ultrasonography and computed tomography demonstrated a large heterogeneous mass in the right hepatic lobe. A right hepatectomy was performed. The tumor weighed 2850 g and microscopic section revealed a peculiar random pattern, the so-called patternless pattern of spindle tumor cells separated by abundant thick collagen bands. The tumor presented a number of highly cellular areas composed of plump spindle cell with hyperchromatic nuclei and rare mitotic figures. Ninety percent of the neoplastic cells displayed strong immunoreactivity for CD 34/My 10. The postoperative course was uneventful and the patient is alive and well without recurrence 6 years after surgery. Received for publication on June 16, 1997; accepted on Oct. 27, 1997     

Solitary fibrous tumor of the peritoneum found in the prevesical space

Solitary fibrous tumors (SFT) are well recognized in the pleura, but their rare occurrence at other sites has become appreciated only in recent years. We experienced a 68-year-old male patient who presented with frequency of urination and difficulty in voiding. Computed tomographic scan revealed a solid and cystic mass which measured 12 x 10 cm in the prevesical space. This tumor showed typical histopathologic features of SFT, and was immunostained positive for vimentin, CD34 and CD99. This is an extremely rare case of SFT arising from the parietal peritoneum found in the prevesical space.     

Solitary fibrous tumor of the pancreas: Case report and review of the literature

Solitary fibrous tumor (SFT) is a mesenchymal tumor typically located in the pleura, but can also be found as an asymptomatic mass in other areas, including the liver, peritoneum, kidney and salivary glands. However, SFT rarely locates in the pancreas. We present such a case of pancreatic SFT, along with a review of all reported cases. A 55-year-old man was treated surgically for an asymptomatic pancreatic mass after a rigorous preoperative control. Histologic examination of the resected specimen showed characteristics of an SFT. As only 15 cases of pancreatic SFT have been reported so far, an attempt to compare the cases was considered intriguing. We found that patients with pancreatic SFT were mainly women (81.25%), with a median age of 54 years at the time of diagnosis and a median tumor size of 5.83 cm. Pancreatic SFTs were revealed incidentally in 50% of cases, and all of them showed an enhancement through arterial computed tomography. All tumors were positive for CD34, ten were positive for Bcl-2, and twelve were negative for S100. The diagnosis of this pancreatic tumor is established by a combination of clinical suspicion, imaging procedures and histological findings, and is confirmed by immunohistochemical staining. Although the behavior of SFTs is rather benign, close clinical follow-up is recommended due to a potentially malignant nature.     

Solitary fibrous tumors arising in abdominal wall hernia sacs.

Solitary fibrous tumor (SFT) of the peritoneum is an unusual spindle-cell neoplasm. SFT was originally described in the pleura; however it is now diagnosed in multiple extrathoracic sites. Most believe that the tumor is of mesenchymal origin and should be classified as a variant of fibroma. SFT of the pleura and peritoneum have also been called fibrous mesothelioma, and the cell of origin is felt to be a pluripotential submesothelial mesenchymal cell. Primary tumors arising in hernia sacs are rare, and we report on two patients with hernia SFT. The first is a 67-year-old man who had a diffusely thickened distal left inguinal hernia sac. Within the sac was copious myxoid material mimicking pseudomyxoma peritonei. Herniorrhaphy and orchiectomy were performed. The second is a 44-year-old woman with a midepigastric mass attached to a ventral hernia. Wide local excision was performed. Both tumors demonstrated plump spindle cells, one with myxoid background and the other with keloidal collagen. Calretinin immunostaining was positive in both tumors, whereas CD34 was negative. This suggests tumor origin from a submesothial pluripotential cell that maintains potential for mesothelial differentiation. Surgical excision is the treatment of choice with the degree of resectability being a powerful predictor of outcome.     

Solitary fibrous tumor of the meninges: two new cases and review of the literature

BACKGROUND

Solitary fibrous tumor (SFT), a mesenchymal neoplasm originally described in the pleura has been more recently reported to arise in a number of other sites, including the meninges. Nowadays immunohistochemistry facilitates the otherwise problematic differential diagnosis with regard to other benign and malignant spindle cell neoplasms of the central nervous system.

METHODS

Two recently treated cases of meningeal SFT (one craniospinal, one spinal) are presented and discussed in the light of the present knowledge and a review of the literature.

RESULTS

Total resection was followed by complete recovery and both patients are presently asymptomatic and without evidence of disease. The microscopic and immunohistochemical profiles (CD 34, vimentin positive; S-100, EMA negative) were consistent with those of previously reported cases.

CONCLUSIONS

The majority of SFTs behave in a benign fashion and do not recur unless subtotally resected. Malignant variants may account for up to 37% of SFTs in other locations but have never been reported to occur in the meninges. Meningeal SFTs are to be considered a new pathological entity. Wider use of immunohistochemical screening should enable the determination of their real incidence; larger series and longer follow-up will provide conclusions about their treatment and prognosis.     

Solitary fibrous tumor of renal pelvis

A 70-year-old Japanese man was referred because of a right renal mass of 2 years in duration. Imaging studies, including magnetic resonance imaging, revealed an ovoid mass, with relatively abundant vascularity, in the right renal pelvis. Right radical nephrectomy was done and a tumor measuring 6.0 x 4.5 x 4.0 cm was found in the renal pelvis. Solitary fibrous tumor (SFT) was highly suspected by histology. Immunohistochemical study using a monoclonal antibody directed against the human hematopoietic progenitor cell antigen (CD34) stain confirmed SFT. This is the first case of SFT of the renal pelvis. Although SFT is extremely rare in urogenital organs, this tumor must be included in the differential diagnosis when we encounter urogenital tumors consisting of mesenchymal elements.     

A case report: retroperitoneal inflammatory fibrosarcoma that revealed progressive enlargement

A 65-year-old woman presented with microscopic hematuria. Computed tomography (CT) and magnetic resonance imaging revealed a solid tumor measuring 64 x 55 x 71 mm adjacent to the right kidney. After 51 days, the CT demonstrated progressive enlargement of the tumor (110 x 80 x 82 mm), and the tumor-doubling time was calculated as 33 days. A transperitoneal right radical nephrectomy was performed. Histologically, the tumor was arising from retroperitoneum and consisted of variable arranged spindle cell proliferation with an infiltration of inflammatory cells. Immunostaining examination showed positive staining for alpha-smooth muscle actin (SMA), vimentin, cytokeatins, and CD 68, whereas desmin, CD 34, and p53 were negative. High proliferative activity (20%) was demonstrated by MIB1 immunostaining. Then the tumor was diagnosed as inflammatory fibrosarcoma. The patient has been followed up for 3 months since the operation with no evidence of local recurrence or distant metastasis.     

Solitary fibrous tumor of the pelvis: an uncommon soft-tissue tumor. A case report

A rare case of Solitary fibrous tumor (SFT) of the pelvis is reported. A 76-years-old man presented with a low abdominal pain, acute urine retention and constipation. Imaging studies (US, CT MR) showed an 17 x 10 x 9 ovoid mass in the pelvis, dislocating bladder and rectum. Finally, trans-rectal needle biopsy suggested the diagnosis of SFT. En bloc excision of tumor and rectum (because of strong adhesions) was performed. Histological examination showed spindle and fibroblastic-like cells dispersed in collagenous areas with positive stains for CD34, bcl-2, CD99 and it confirmed diagnosis of SFT. No postoperative complications occurred, only vesico-sphincter dyssynergia was found by urodynamics. After 5 years, patient is disease-free. SFT is, usually, benign tumor with slow growth and excellent prognosis. Complete surgical resection is the only curative treatment. However, 10-15% of SFT are malignant and histological findings cannot always predict clinical behaviour. For this reason, careful and long term follow-up is necessary after surgery.     

Case of retroperitoneal solitary fibrous tumor

Solitary fibrous tumor (SFT) of the retroperitoneal space is rare. We report a case of retroperitoneal tumor, diagnosed as SFT. A 69-year-old woman presented with right lower abdominal swelling, and was referred to our hospital with suspicion of right renal tumor. Abdominal ultrasound and computerized tomography (CT) showed a mass (about 15 x 14 x 10 cm) in the right abdomen. The tumor was thought to be right renal rumor, and right radical nephrectomy was performed. In the excised specimen the tumor was not connected to gastrointestinal tract, peritoneum, or right kidney. The histological and immunohistochemical examination of the specimen revealed SFT. The tumor has malignant potential with partially increased mitotic activity and cellularity in the histological examination. The patient is healthy and without evidence of recurrence or metastasis 26 months from surgery.     

Solitary Fibrous Tumor in the Retroperitoneal Space: Report of a Case

Solitary fibrous tumors (SFTs) are spindle-cell neoplasms originally described in the pleura. It is now known that these tumors can develop in many sites. This report describes the case of a well-circumscribed tumor located around the superior mesenteric artery (SMA), which was initially thought to be either a superior SMA aneurysm, a lymphoma, or a neurogenic tumor. Histological examination demonstrated the tumor to be composed of a cellular proliferation of ovoid to spindle cells with a fine collagenous matrix in the short fascicles. Immunohistochemical staining was strongly positive for CD34 and negative for factor VIII, cytokeratin, desmin, and muscle-specific actin (HHF-35). These findings suggested a diagnosis of SFT in the retroperitoneal space. To our knowledge, this is the first report of an SFT located around the SMA. Based on the above findings, it is important to include SFT in the differential diagnosis of retroperitoneal tumors located around the SMA. Received: August 13, 2001 / Accepted: March 5, 2002 Reprint requests to: M. Kume     

Primary solitary fibrous tumor (SFT) in the retroperitoneum

BACKGROUND: Solitary fibrous tumor (SFT) is an infrequent but distinct neoplasm, which generally arises from submesothelial connective tissue in the pleura. SFT is rarely recognized in extrathoracic sites, and histologically identical conditions have also been reported in the retroperitoneum, although their pathophysiology has not been extensively investigated. METHODS: We present four cases of primary SFT in the retroperitoneum, and review 37 similar cases in the previous literature. RESULTS: About 40% of patients were asymptomatic, and 19.2% and 15.4% presented with an abdominal mass and urinary symptoms, respectively. The tumor size ranged between 2 and 26 (mean 9.1) cm. Sixty-three percent of tumors showed nonspecific development with haphazard distribution of bland short spindle or polygonal cells with or without collagenous bundles and stromal hyalinization. In 22.0%, hemangiopericytomatous appearance was seen. About 15% of cases showed histologically malignant characteristics. The tumor cells were immunoreactive for vimentin in all cases, CD34 in 91% and Bcl-2 in 86%. All tumors were excised, and in 85.4% of cases, tumors did not recur postoperatively for 6 to 48 months. No significant difference was found between the recurrence rate of histologically benign and malignant cases. Cases positive for both CD34 and Bcl-2 had no recurrence. CONCLUSIONS: The identification of SFT in the retroperitoneum is of importance because histopathological indicators of malignancy are not necessarily associated with clinical malignant potential in many cases of retroperitoneal SFT. Retroperitoneal SFT showing typical pathological features with expression of CD34 and Bcl-2 is associated with a favorable outcome following excision.     

Solitary fibrous tumor of the pleura; report of a case

An 81-year-old male appealed against a feeling of dyspnea, and consulted the hospital. The giant tumor discovered in the thorax and it was enlarging gradually for 7 years. The tumor shadow with a diameter of about 15 cm was noted in right lower lung field on the chest X-ray. A definite diagnosis was not obtained by the needle biopsy. The tumor was found to exist between upper lobe and lower lobe and pressed lower lobe at surgery. The tumor was completely excised with partial resection of the collapsed lower lobe. The tumor was 1,050 g in weight and 18 cm in maximum diameter. Pathological examination showed the irregular and plan-like arrangement of the spindle-shape cell. Immunohistochemical study revealed positive findings for bcl-2 and CD34, negative findings for desmin, ketatin, and alpha-actin. The tumor was diagnosed as malignant solitary fibrous tumor of the pleura due to highly atypical nuclear finding with an abundant nuclear fission or histology.     

肠系膜纤维瘤、孤立性纤维性肿瘤和胃肠道间质瘤的免疫组织化学观察

目的：探讨肠系膜纤维瘤（MF）、孤立性纤维性肿瘤（SFT）和胃肠道间质瘤（GIST）的免疫组织化学鉴别诊断。方法：运用组织芯片结合免疫组织化学技术对3种肿瘤进行CD117、CD34、β-catenin、S-100、Desmin、Bcl-2和Dog-1的免疫组织化学分析。结果：75%的MF为β-catenin阳性表达,而13例GIST和7例SFT均为阴性表达;85%的GIST为CD117阳性表达,92%的GIST为Dog-1阳性表达,25%的MF为Dog-1阳性表达,8例MF均为CD117阴性表达,7例SFT则CD117和Dog-1均为阴性表达;71%的SFT表达CD34和Bcl-2,而23%的GIST表达为CD34阳性。结论：组合应用CD117（或Dog-1）、CD34和β-catenin并结合HE染色切片的形态特点可以有效地鉴别深部MF、SFT和GIST。配合应用S-100和Desmin,可以进一步排除肌源性和外周神经源性肿瘤。     

Solitary Fibrous Tumor of the Pleura: An Analysis of 13 Cases

BACKGROUND: Solitary fibrous tumor of the pleura is a rare soft-tissue tumor. In search of appropriate diagnosis and treatment methods, we present our experience with 13 patients. METHODS: The medical charts of 13 patients treated during the last 5 years were reviewed, as well as pathological records, including immunohistochemical stains. Follow-up data were obtained. In addition, a literature review with regard to treatment and clinical outcome was performed. RESULTS: Our series consisted of four men and nine women with a mean age of 47 years. Two were diagnosed before operation with ultrasonography-guided core needle biopsy. All patients underwent primary surgical treatment, and four of them were resected by video-assisted thoracic surgery. Seven tumors were malignant and the other six were benign. Immunohistochemical staining showed nestin was positive in three malignant solitary fibrous tumors of pleura (3/7), which were negative for CD34. Except for one, all patients were followed-up for 3 to 35 (mean, 14.5) months. Among them, one patient experienced a recurrence and one patient died of brain metastasis. CONCLUSION: Ultrasonography-guided core needle biopsy combined with immunohistochemical analysis might be a safe and rapid method to provide a confirmatory diagnosis before resection. For smaller, pedunculated tumors, video-assisted thoracic surgery could be a powerful and useful approach. We speculate that CD34-negative and nestin-positive might be a malignant marker for solitary fibrous tumor of pleura.     

Solitary fibrous tumor of the adrenal gland with renal cell carcinoma and angiomyolipoma at the same time; a case report

Solitary fibrous tumor (SFT) is a neoplasm of pleura and its occurrence in the retroperitoneal space is rare. We report a case of SFT of the adrenal gland associated with ipsilateral renal cell carcinoma (RCC) and angiomyolipoma (AML). A 48-year-old woman was referred to our hospital for a left renal AML. Computed tomography (CT) in our hospital showed a left adrenal mass (25 x 20 mm). Because the adrenal tumor was nonfunctioning, she was followed at outpatient clinic. Four years later, CT showed an increase in the left adrenal tumor size (42 x 30 mm) and a left RCC. Left adrenectomy and partial nephrectomy for RCC and AML were simultaneously performed. Histological examination revealed adrenal SFT and clear cell carcinoma and AML of the kidney. We present a brief review on histological characteristics of retroperitoneal SFT and its occurrence in the adrenal grand region.     

Solitary fibrous tumors of the pleura presenting satellite tumors

A 29-year-old man presented with a mass in the left lower lung field on a chest radiograph obtained during a medical checkup. Computed tomography revealed a tumor adjacent to the diaphragm. A sessile tumor measuring 10.5 × 8.5 × 4.5 cm arising from the parietal pleura was resected. The tumor was accompanied by several little tumors on the nearby diaphragm. Pathologically, the major tumor consisted of typical spindle-shaped cells with myxoid degeneration. There was no increased cellularity, cellular pleomorphism, or a high mitotic count. In immunohistochemical studies, the spindle cells showed positive staining for CD34 and were negative for bcl-2. The smaller tumors also consisted of myxoid degeneration. We diagnosed benign solitary fibrous tumor of the pleura with satellite tumors. We must be aware of the possibility of satellite tumors when we treat patients with a benign solitary fibrous tumor.