Rare presentation of solitary fibrous tumour in the floor of the mouth.

A male in his 20s, a tobacco chewer, presented to the outpatient department with a history of painless, slowly progressive swelling in the floor of the mouth. After a thorough history and clinical examination, MRI was done and the tumour was completely excised. Histopathological examination revealed the mass to be a solitary fibrous tumour, confirmed with immunohistochemical markers. On subsequent follow-ups, the patient was found to be asymptomatic with no clinical signs of recurrence.

177 Lu-FAP-2286 Therapy in a Metastatic Bone Malignant Solitary Fibrous Tumor.

ABSTRACT: A 57-year-old woman with a metastatic bone malignant solitary fibrous tumor received 177 Lu-FAP-2286 therapy. After 1 treatment cycle, 68 Ga-FAP-2286 PET/CT revealed remission of the lesions. Moreover, the patient did not report any adverse effects.

Intense PSMA Uptake in Solitary Fibrous Tumor of the Seminal Vesicle.

ABSTRACT: Solitary fibrous tumor arising from the seminal vesicle is very rare. We describe 18 F-PSMA-1007 PET/CT findings in a case of prostate adenocarcinoma with a solitary fibrous tumor of the left seminal vesicle. The solitary fibrous tumor showed intense 18 F-PSMA-1007 uptake mimicking metastatic prostate adenocarcinoma. This case indicates that solitary fibrous tumor may cause false-positive result when using PSMA PET in staging of prostate cancer.

Surgical Management of Craniospinal Axis Solitary Fibrous Tumors: A Single-Institution Case Series and Comprehensive Review of the Literature.

BACKGROUND AND OBJECTIVES: Meningeal solitary fibrous tumors (SFTs) comprise 0.4% of primary central nervous system neoplasms and carry metastatic potential. Disease course and optimal management are largely unknown, and there is currently no literature rigorously describing neurological outcomes in surgically managed SFTs. We present one of the largest craniospinal SFT series, analyze patient outcomes, and extensively review the associated literature. METHODS: All surgically managed SFTs at our institution between January 2005 and March 2023 were retrospectively reviewed. Patient demographics, tumor and radiographic features, treatment, and clinical outcomes were collected. Neurological function was quantified using Frankel grade and Neurologic Assessment in Neuro-Oncology scores. Descriptive statistics, multivariate analysis, log-rank test, and Kaplan-Meier survival analysis were performed. RESULTS: Twenty-one patients satisfied inclusion criteria. Tumor locations included 15 supratentorial, three infratentorial, and three spinal. All patients underwent surgical resection, and 16 (76.2%) underwent radiation. Six (28.6%) patients had tumor recurrence, and three (14.3%) developed metastasis. Younger age and higher postoperative Frankel grade were significantly associated with increased overall survival (OS) ( P = .011, P = .002, respectively). All patients symptomatically improved or stabilized after surgery, and Neurologic Assessment in Neuro-Oncology score ( P = .001) and functional status significantly improved postoperatively (Karnofsky Performance Status: 65.2 ± 25.2 vs 91.4 ± 13.5, P = .001). Sex, adjuvant radiation, and extent of resection were not significantly associated with OS. CONCLUSION: SFT of the central nervous system is a rare entity with a variable clinical course. Surgical resection was associated with improved postoperative functional and neurological status. Higher postoperative neurological function was significantly associated with OS. Further studies are warranted to validate a standardized treatment algorithm and investigate the efficacy of adjuvant radiation in SFT.

MRI-based radiomics nomogram for distinguishing solitary fibrous tumor from schwannoma in the orbit: a two-center study.

OBJECTIVES: To investigate the value of magnetic resonance imaging (MRI) radiomics for distinguishing solitary fibrous tumor (SFT) from schwannoma in the orbit. MATERIALS AND METHODS: A total of 140 patients from two institutions were retrospectively included. All patients from institution 1 were randomized into a training cohort (n = 69) and a validation cohort (n = 35), and patients from institution 2 were used as an external testing cohort (n = 36). One hundred and six features were extracted from T2-weighted imaging (T2WI) and contrast-enhanced T1-weighted imaging (CET1WI). A radiomics model was built for each sequence using least absolute shrinkage and selection operator logistic regression, and radiomics scores were calculated. A combined model was constructed and displayed as a radiomics nomogram. Two radiologists jointly assessed tumor category based on MRI findings. The performances of the radiomics models and visual assessment were compared via area under the curve (AUC). RESULTS: The performances of the radiomics nomogram combining T2WI and CET1WI radiomics scores were superior to those of the pooled readers in the training (AUC 0.986 vs. 0.807, p < 0.001), validation (AUC 0.989 vs. 0.788, p = 0.009), and the testing (AUC 0.903 vs. 0.792, p = 0.093), although significant difference was not found in the testing cohort. Decision curve analysis demonstrated that the radiomics nomogram had better clinical utility than visual assessment. CONCLUSION: MRI radiomics nomogram can be used for distinguishing between orbital SFT and schwannoma, which may help tumor management by clinicians. CLINICAL RELEVANCE STATEMENT: It is of great importance and challenging for distinguishing solitary fibrous tumor from schwannoma in the orbit. In the present study, an MRI-based radiomics nomogram were developed and independently validated, which could help the discrimination of the two entities. KEY POINTS: • It is challenging to differentiate solitary fibrous tumor from schwannoma in the orbit due to similar clinical and image features. • A radiomics nomogram based on T2-weighted imaging and contrast-enhanced T1-weighted imaging has advantages over radiologists. • Radiomics can provide a non-invasive diagnostic tool for differentiating between the two entities.

Developing a Nomogram to Stratify Intracranial Solitary Fibrous Tumor Recurrence.

RATIONALE AND OBJECTIVES: To develop a nomogram to stratify tumor recurrence (TR) in intracranial solitary fibrous tumors (ISFTs) based on the clinical, radiological, and pathological features. MATERIALS AND METHODS: A total of 215 patients from Beijing Tiantan Hospital, Capital Medical University and 48 patients from Lanzhou University Second Hospital, diagnosed with ISFT based on histopathological findings, were included. The patients were randomly divided into training and test cohorts at a ratio of 8:2. Information regarding clinical, radiological, and histopathological features, and the clinical outcomes was retrospectively analyzed. Univariate and multivariate analyses were performed using the Cox proportional hazard model for TR in the training cohort. A nomogram incorporating the independent risk factors was developed in the training cohort and validated in the test cohort. Its predictive performance was analyzed using the Harrell C-index. Decision curve analysis (DCA) was used to evaluate the net clinical benefit. RESULTS: The Harrell C-indices for TR at 3 and 5 years were 0.845 (0.578-0.944) and 0.807 (0.612-0.901) for the test cohort, respectively. In the test cohort, the nomogram provided a net clinical benefit in the DCA over the TR scheme or non-TR scheme. Although postoperative radiotherapy (PORT) was useful for TR prevention, high doses (≥46 Gy) were not superior to lower doses in prolonging the progression-free survival. CONCLUSION: The nomogram obtained in our study had a good predictive performance and could be used for ISFT patients.

Locally advanced solitary fibrous tumour of the prostate.

Solitary fibrous tumours (SFTs) are rare mesenchymal neoplasms composed of spindle cells, most often occurring in the pleura. SFTs arising from the prostate are exceptionally rare, with only around 40 cases reported in literature to date. We report a man in his 60s who was referred to our clinic for elevated prostate-specific antigen and presented with mild obstructive lower urinary tract and defecatory symptoms. Prostate needle-core biopsy revealed neoplastic spindle cells that strongly expressed CD34. Cross-sectional imaging demonstrated a 12 cm locally advanced heterogeneous prostate mass with intravesical extension and mass effect on the anterior rectum. Radical cystoprostatectomy with orthotopic neobladder reconstruction was performed, and the diagnosis of primary prostatic SFT was made based on histological characteristics and immunophenotyping. We present diagnostic, clinical management and prognostic considerations in patients with primary prostatic SFT.

Solitary fibrous tumor of the seminal vesicle.

Solitary fibrous tumors (SFTs) are mesenchymal neoplasms with variable clinical behavior depending on age, tumor site, and size, and pathologic factors such as mitoses and necrosis. Imaging features on computed tomography (CT) or magnetic resonance imaging (MRI) are not specific, and the diagnosis relies on histopathology with immunohistochemistry. SFTs arising from seminal vesicles is rare and reported in only eight earlier cases. We discuss the clinical, histopathologic and positron emission tomography (PET) imaging characteristics of a 54-year-old patient with SFT of the seminal vesicle. The patient was treated with robot-assisted seminal vesiculotomy and is doing well on follow-up at two years.

Solitary Fibrous Tumor in the Retroperitoneal Space Arising from the Diaphragm.

BACKGROUND/AIM: We present a case of solitary fibrous tumor, arising from the diaphragm in the retroperitoneal space, that was resected with robotic assistance. CASE REPORT: An 85-year-old female patient was referred to our hospital for evaluation of a suspected right renal tumor. Abdominal contrast-enhanced computed tomography revealed a tumor (maximum diameter, 36 mm) protruding from the superior pole of the right kidney. The patient was scheduled for robot-assisted, retroperitoneoscopic, partial nephrectomy based on a preoperative diagnosis of renal cell carcinoma. Intraoperative findings revealed that the tumor originated from the diaphragm and had no continuity with the renal parenchyma. Pathological examination revealed a solitary fibrous tumor. CONCLUSION: Solitary fibrous tumors are rare soft-tissue neoplasms with a distinct molecular feature of the fusion of nerve growth factor-inducible A gene-binding protein 2 with signal transducer and activator of transcription 6 gene (NAB2::STAT6). We believe that this is the first reported case of a solitary fibrous tumor arising from the diaphragm in the retroperitoneal space.

Intracranial Solitary Fibrous Tumor Mimicking Meningioma.

Solitary fibrous tumor (SFT) is a clinically rare tumor derived from mesenchymal spindle cells. Central nervous system SFT represents only 0.09% of tumors occurring on the meninges, while intracranial solitary fibrous tumors (ISFT) are even more rare. Due to the similar genetic characteristics it shares with hemangiopericytoma, in 2016, the World Health Organization (WHO) classified it as a single disease called solitary fibrous tumor (SFT)/hemangiopericytoma. We reported a case of a 60-year-old female with an intracranial solitary fibrous tumor (ISFT). The patient's magnetic resonance imaging showed a mass adhering extensively to the dura mater, with adjacent thickening of the meninges and evidence of a meningeal tail sign. These radiologic findings suggested a meningioma. The tumor was surgically removed and sent for pathologic examination, which confirmed that the tumor was consistent with a solitary fibrous tumor(WHO III). Due to its rarity and similarities with meningioma, ISFT is often misdiagnosed as other types of brain tumors. ISFT is poorly understood and poses a diagnostic challenge. Our case report presents several features suggestive of meningioma, but histopathological examination after surgery confirmed the diagnosis of SFT. Knowledge of these tumors is crucial for neurosurgeons to include them in preoperative differential diagnosis.

Surgical removal of an unusual huge solitary fibrous tumor in the mediastinum: a case report.

BACKGROUND: Intrathoracic Solitary Fibrous Tumors (SFT) mainly arise from the pleura; however, these tumors may also originate from the mediastinum. We present a rare case of posterior SFT extending to several mediastinal sites and with an unusual large size, successfully treated with surgical resection. CASE PRESENTATION: A 66-year-old female presented with an initial manifestation of ambiguous pain in the chest and dysphagia and later developed pitting edema in both lower extremities and cachexia five months before admission. Chest imaging confirmed a mediastinal mass (17 × 15 × 8 cm) which was surgically removed. Immunohistochemistry confirmed the diagnosis of a solitary fibrous tumor with positive B-cell lymphoma 2, STAT6, and CD99, negative S100 and smooth muscle actin, and low levels of Ki67 (5-7%). The patient's follow-up course was unremarkable. CONCLUSION: Mediastinal SFTs may grow extremely huge, with the potential to invade multiple adjacent sites. Surgical removal of the tumor remains the mainstay of treatment in these cases.

Large Solitary Fibrous Tumor (SFT) of the penis- a case report and review of literature.

BACKGROUND: Solitary fibrous tumors (SFTs) are very rare spindle cell neoplasms of mesenchymal origin with largely benign course of disease. Genital SFT's can be managed providing excellent functional and psychological outcomes by timely intervention. CASE PRESENTATION: We report the largest and possibly the second only reported case of penile SFT in a 34 year male presenting with a gradually increasing perineal mass with clinically normal appearing phallus. MRI revealed a 9.8 × 3.2 cm soft tissue mass arising from left corpora cavernosae, the mass was excised en-bloc via a perineal approach under spinal anaesthesia. Histopathology revealed spindle cell tumor embedded in myxohyaline stroma along with hyalinized vascular channels demonstrating IHC positivity for CD34 and STAT6. The patient is disease free post 2 years of resection with no sexual or urinary dysfunctions. CONCLUSION: Genital SFTs, although rare, should be considered in the differential diagnosis of well-circumscribed, painless, slow growing solid masses and histopathologists must be vigilant of its malignant characteristics.

Solitary fibrous tumor resembling pulmonary fractionation disease: A case report.

RATIONALE: Preoperative differentiation between pulmonary fractionation and solitary fibrous tumors (SFTs) is challenging. Diaphragmatic primary tumors are relatively rare among SFTs, with limited reports of abnormal vascularity. PATIENT CONCERNS: A 28-year-old male patient was referred to our department for surgical resection of a tumor near the right diaphragm, Thoracoabdominal contrast-enhanced computed tomography (CT) scan revealed a 10 × 8 cm mass lesion at the base of the right lung. The inflow artery to the mass was an anomalous vessel in which the left gastric artery bifurcated from the abdominal aorta, and its origin was the common trunk and right inferior transverse artery. DIAGNOSIS: The tumor was diagnosed as right pulmonary fractionation disease based on the clinical findings. The postoperative pathological examination determined a diagnosis of SFT. INTERVENTIONS: The pulmonary vein was used to irrigate the mass. The patient was diagnosed with pulmonary fractionation and underwent surgical resection. Intraoperative findings revealed a stalked, web-like venous hyperplasia anterior to the diaphragm, contiguous with the lesion. An inflow artery was found at the same site. The patient was subsequently treated using a double ligation technique. The mass was partially contiguous with S10 in the right lower lung and stalked. An outflow vein was identified at the same site, and the mass was removed using an automatic suture machine. OUTCOMES: The patient received follow-up examinations that involved a chest CT scan every 6 months, and no tumor recurrence was reported during 1 year of postoperative follow-up. LESSONS: Differentiating between SFT and pulmonary fractionation disease may be challenging during preoperative diagnosis; therefore, aggressive surgical resection should be considered as SFTs may be malignant. Identification of abnormal vessels using contrast-enhanced CT scans may be effective in reducing surgical time and improving the safety of the surgical procedure.