Malignant solitary fibrous tumor of the kidney: report of the first case managed with interferon

Malignant renal hemangiopericytoma: a case report

Malignant hemangiopericytoma (HPC) is an uncommon disease first described by Stout and Murray in 1942. Patients with suspected renal HPC on admission sometimes complain of low back pain, hematuria, or hypertension. A combination of histochemical and anatomo-pathologic examinations is necessary to confirm the diagnosis of renal HPC. We report the case of a 41-year-old female patient who had persistent painful nodular lesion at the right lower back and gross hematuria. Based on analyses of clinical symptoms and signs plus radiological a laboratory examination, she was diagnosed with renal cell carcinoma of the right kidney. She subsequently underwent open right radical nephrectomy via transperitoneal approach. The patient was discharged from hospital in good condition on Day 5 of care after surgical intervention. Malignant HPC of the kidney is an uncommon disease that can be diagnosed based on multislice computerized tomography angiography plus histopathological examination using the periodic acid shift method. Management of malignant renal HPC requires radical nephrectomy followed by chemotherapy. This case study provides important preliminary data for further studies of patients with renal HPC in Indonesia.

A case of incidentally discovered solitary fibrous tumor of the kidney: A case study

Solitary fibrous tumor (SFT) is a rare neoplasm of mesenchymal origin. The kidney represents an unusual location for SFT and the diagnosis and treatment of renal SFT remains challenging. The present study reports the case of a right kidney SFT incidentally discovered in a 52-year old woman. Radiological findings from computed tomography and magnetic resonance imaging were not specific but highly suspect for a malignant neoplasm. The definitive diagnosis relied on histological examination and immunohistochemical staining for CD34 and signal transducer and activator of transcription 6.

Giant Cell-Rich Solitary Fibrous Tumor in the Nasopharynx: Case Report and Literature Review

Solitary fibrous tumors (SFTs) can occur in several locations outside the pleura, but rarely in the sinonasal tract, and particularly not in the nasopharynx. Herein, we describe an unusual case of giant cell-rich SFT (GCRSFT) occurring in the nasopharynx. A 64-year-old man experienced dizziness and headache for more than 10 years with no obvious cause. Computed tomography (CT) scan showed a 3.9 cm × 2 cm tumor on the posterior lateral wall of the left nasopharynx, and angiography revealed a hypervascular tumor fed by branches of the left carotid artery. Hence, preoperative embolization was performed, and then the tumor was endoscopically resected. The symptoms were relieved after the resection, and postoperative head CT and video laryngoscopy showed that the tumor was completely resected. We next characterized the specific pathological characteristics of the resected tumor. Histologically, the tumor was characterized by varying cellular proliferation of cytologically bland spindle cells within a collagenous stroma, with prominent interspersed branching vessels. Mitotic activity was low (2/50HPF), and there was no evidence of pleomorphism or tumor necrosis. Moreover, multinucleated giant cells with deep nuclear staining and distributed in pseudovascular spaces were found within the tumor. We ruled out the possibility that our case was giant cell fibroblastoma (GCF) by immunohistochemical analysis, showing that the tumor cells were positive for CD34, CD99, STAT6, and BCL-2, and that the Ki-67 labeling index was 3%, indicating that our case was SFT and not GCF. The patient's condition is generally good after a 14-month follow-up. This report serves to broaden the morphologic spectrum of GCRSFT and will help clinicians and pathologists better understand this entity to prevent misdiagnosis.

Solitary fibrous tumor of the liver - An unusual entity: A case report and review of literature

Solitary fibrous tumor (SFT) of the liver is a rare entity and its presentation is usually delayed till they grow to a substantial size. Clinico-radiological features are non-specific, contributing to increase in the diagnostic dilemma. Definitive diagnosis of SFT is usually made based on the histological features and immunohistochemistry data of the resected specimen. In this case report, we describe the case of an elderly male who presented with a large mass in the left lobe of the liver with normal level of tumor markers and atypical radiological findings. The patient successfully underwent resection of the tumor and the diagnosis was confirmed on histopathology.

Clinical analysis of 47 cases of solitary fibrous tumor

The aim of the present study was to summarize the clinical manifestations, diagnosis, treatment, and prognosis of solitary fibrous tumor (SFT). In total, 47 cases of SFTs diagnosed by postoperative pathology between January 2002 and September 2014 were retrospectively reviewed, and the general information, clinical manifestations, imaging techniques, treatment, pathology and follow-up findings were analyzed. Of the 47 patients, clinical characteristics were collected in 37 cases (18 men and 19 women; mean age, 44.1 years; age range, 13-72 years). The maximum diameters of the tumors were 1.5-25 cm, with a mean diameter of 8.8 cm. The symptoms were various and non-specific. Imaging examinations following iodinated contrast administration showed the SFTs to be well-defined, cystic or solid mass and enhanced. On color Doppler ultrasound, SFTs were described as hypoechoic, clear, irregular masses. All patients underwent surgical resection, and SFT was diagnosed by postoperative pathological and immunohistochemical examination. Of the 47 patients, 25 received complete follow-up of 5-130 months, with a median follow-up period of 35.2 months, that included a color Doppler ultrasound or computed tomography (CT) scan every 6-12 months. At the end of the follow-up period all patients were alive and healthy, with the exception of one patient, who presented with recurrence 15 months after surgery. The findings of the present study showed SFT to be a rare systemic disease with no particular clinical manifestations. In the cases reviewed in the present study, CT, magnetic resonance imaging scans and color Doppler ultrasound were important for the diagnosis of SFT, while the definitive diagnosis relied on pathological and immunohistochemical examinations. Surgery, the primary treatment for SFT, was performed, and, following complete removal of the tumor, the prognosis was favorable.

Variable Solitary Fibrous Tumor Locations: CT and MR Imaging Features

The aim of the study is to describe the radiological imaging features of different solitary fibrous tumors (SFTs) locations and present histopathological correlations. From 2007 to 2013, 20 cases of histologically confirmed that SFTs were retrospectively analyzed with computed tomography (CT; 9/20), magnetic resonance imaging (MRI; 5/20), or both CT and MRI (6/20). All 20 SFTs were well defined, lobular, soft-tissue masses, and 60% were located outside of the pleura. One pleural case invaded to the 10th thoracic vertebra and had lung metastases. Images revealed 11 heterogeneous lesions that exceeded 3.0 ± 0.203 cm along the greatest axis with patchy necrotic foci, and 9 homogeneous lesions <3.0 ± 0.203. Microscopically, all SFTs were proliferative spindle cells with varying degrees of fibrosis and interspersed vessel branching. Cells were strongly immunopositive for CD34. Here we review variable imaging findings of SFTs, which can be within the pleura as well as within other serosal tissues such as the meninges and postperitoneum. SFTs > 3.0 ± 0.203 cm along the greatest axis appeared to be mixed patterns, whereas SFTs < 3.0 ± 0.203 cm had isodense appearances. SFTs cells were CD34 immunopositive and surgery was a first-line treatment choice.

A GRIA2 and PAX8-positive renal solitary fibrous tumor with NAB2-STAT6 gene fusion

Solitary fibrous tumor (SFT) is a rare neoplasm composed of mesenchymal-derived spindle cells. Although SFT occurs anywhere in the body, they most frequently affects the thoracic region. Here, we reported an extremely rare case of an extrathoracic SFT occurring primarily in the kidney. To our knowledge, little information has been described on the immunohistochemistry (IHC) and genetics of renal SFT.

A 41-year old Japanese female came to our hospital for further examination of a left kidney mass detected incidentally with ultrasound. Extensive investigation of the tumor, including physical, laboratory, and image examinations led to a clinical diagnosis of renal cancer (cT1aN0M0), which were in most parts imbedded in the lower polar parenchyma. The patient underwent laparoscopic radical nephrectomy. The mass was diagnosed pathologically as SFT originating from the kidney, but not as renal carcinoma. Microscopically, the tumor was composed of spindle-shape cells distributed variably in dense collagenous stroma and had a focal hemangiopericytomatous staghorn-like vascular pattern. Mitotic figures, atypical structures, necrosis and hemorrhage were not identified. No adjuvant therapies were given postoperatively. The patient has been free of tumor recurrence for 25 months since the surgery. IHC revealed that the tumor diffusely expressed CD34, CD99, Bcl2, PAX8, NAB2, STAT6, and GRIA2. The tumor stained negatively for desmin, S-100, c-Kit, CK-AE1/AE3, CDK4 and MDM2. A NAB2-SATA6 gene fusion was detected in tumor cells by reverse transcription-polymerase chain reaction, direct sequencing, and an in situ proximity ligation brightfield assay. The gene fusion occurred as an 831 bp truncation of exon 2 in NAB2 connected to the beginning of exon 3 in STAT6. We have reported a case of GRIA2 and PAX8-positive SFT occurring primarily in the kidney with such NAB2-STAT6 gene fusion for the first time. Diffuse expression of PAX8 in the tumor might present with a renal origin. Reportedly, benign histology of SFT cannot necessarily predict favorable clinical prognosis. Genetic alterations recently identified in SFT could possibly refer to risk stratification for tumor recurrence. However, malignant preponderance of extrathoracic SFT over thoracic SFT remains unexplained so far. Long-term follow-up after surgery should be performed in the present case.

Solitary fibrous tumor of the kidney with focus on clinical and pathobiological aspects

Renal solitary fibrous tumor (SFT) is a rare, and a large scale study on this topic is lacking to date. In this article, we summarize the previously reported cases. The symptoms and signs resemble those of renal cell carcinoma, including hematuria, flank/abdominal/lumbar pain and palpable abdominal mass. Grossly, the tumor demonstrates a well-circumscribed solid mass. Microscopically, the tumor consists of fusiform or ovoid spindle cells and a various amounts of collagen bundles with patternless, storiform, or fascicular arrangements with an occasional hemangiopericytomatous pattern. Immunohistochemically, CD34, CD99 and bcl-2 are often detected. Ultrastructurally, tumor cells contain irregular nuclei, prominent Golgi apparatus, branching rough endoplasmic reticulum, variable numbers of mitochondria. Surgical resection is considered to be the gold standard therapy. Most of renal SFT are benign, but cases of approximately 10 to 15% behave in an aggressive fashion. All patients need to be on long-term follow-up because clinical behavior is rather unpredictable. As the molecular genetic study of renal SFTs is lacking, a large scale study will be desirable in the future.

Renal malignant solitary fibrous tumor with single lymph node involvement: report of unusual metastasis and review of the literature

Solitary fibrous tumors are rare mesenchymal spindle cell neoplasms that are usually found in the pleura. The kidneys are an uncommon site and only few cases of renal solitary fibrous tumor exhibit malignant behavior metastasizing to the liver, lung, and bone through the hematogenous pathway.

A huge malignant solitary fibrous tumor of kidney: case report and review of the literature

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1603694556107408.

Solitary fibrous tumor (SFT) is a spindle cell neoplasm that rarely occurs in the kidney. Malignant SFT of the kidney is particularly rare. Here, we report a 66-year old woman with a right flank mass that has been proved clinically and radiographically. Grossly, the largest diameter of the mass were measured up to 23 cm, was poorly circumscribed. Approximately 80% of the neoplasm consisted of hyperchromatic and pleomorphic spindled cells surrounding staghornlike blood vessels. Tumor cells frequently had mitoses and necrosis. However, the remainder of the mass was composed of haphazard, storiform or short fascicular arrangements of spindle cells in a loose myxoid to fibrous stroma. Immunohistochemically, we observed diffusely strong CD34 staining and an 85% Ki-67 proliferative index. The tumor partly showed negative CD34 and a 20% proliferative index. To our knowledge, this is the largest malignant renal SFT in the reported literatures and shows an obviously high proliferative index.

Malignant solitary fibrous kidney tumor with peritoneal disease: a case report

We report a case of a large malignant solitary fibrous kidney tumor. A complete surgical resection of the primary tumor and peritoneal disease was carried out, and a histological examination confirmed the initial diagnosis. We describe and discuss the characteristics of this rare kidney neoplasm.