Solitary fibrous tumor occurring in the colon as submucosal mesenchymal lesion: report of two cases and review of the literature

Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm most often arising from the pleura and rarely in extra-pleural locations, including the gastrointestinal tract. We describe two cases of a SFT presenting as submucosal colonic lesion and review the literature on this lesion. One submucosal lesion was localized in the cecum and was 10 mm in size. The second lesion presented as a 17 mm submucosal rectal lesion. Both lesions presented as well-circumscribed submucosal lesions arranged in short fascicles, blending with abundant collagenous stroma. In both cases, the spindle cells were positive for CD34, STAT6 and CD99, and molecular studies showed NAB2:STAT6 fusion supporting the diagnosis of SFT. Both patients are alive and well 10 and 5 years post-excision, respectively. In conclusion, SFT can occur in the colon as a submucosal lesion and should be included in the differential diagnosis of colonic mesenchymal lesions.

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.

Orbital Solitary Fibrous Tumor in a Commercial Airline Pilot

BACKGROUND: In the literature, central serous retinopathy (CSR) accompanying solitary fibrous tumors (SFT) in a pilot has not been reported. In airline pilots, mass effect-related symptoms such as diplopia, ptosis, etc., seen with orbital tumors may endanger flight safety.CASE REPORT: A 62-yr-old male commercial airline pilot presented with blurred vision in the right eye. He had been receiving treatment for 2 mo because of CSR. His visual acuity was 10/20 in the right eye and 20/20 in the left. During examination, ptosis and exophthalmos were noticed in the right eye. Ocular movements were free in all cardinal directions and there was downward displacement in the right eye. There was no diplopia. Magnetic resonance imaging revealed a 1.5- to 2-cm well-defined contrast-enhancing mass in the lateral extraconal orbit. His medical flight certificate was suspended for 3 mo due to decreased visual acuity and superior visual defect. Superior orbitotomy was performed without any complication. Ptosis and CSR had regressed 1 wk after surgery. All systemic and ophthalmological examinations met aviation medical certificate requirements. He returned to flight on the condition of being checked every 3 mo. At the 1-yr follow-up, there was no sign of recurrences of SFT or CSR.DISCUSSION: SFTs are slow-growing neoplasms that can manifest symptoms related to mass effect. In the current literature, there are no reported cases of the coexistence of orbital SFT and CSR or pilots able to resume flight duties only 1 wk after a successful orbitotomy and tumor resection surgery.Altinbas M, Ozpınar A, Akbaba M, Nacaroglu SA, Sargolzaeimoghaddam M, Sargolzaeimoghaddam M. Orbital solitary fibrous tumor in a commercial airline pilot. Aerosp Med Hum Perform. 2024; 95(6):333-336.

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.

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.

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.

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.

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.

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.

A multicentre retrospective study on extra-thoracic solitary fibrous tumour: preoperative MRI findings predict intraoperative findings and postoperative prognosis

OBJECTIVE

The present study investigated the relationships between the preoperative and operative findings of solitary fibrous tumour (SFT) and between preoperative findings and prognosis.

METHODS

We reviewed 50 SFT patients treated at our musculoskeletal oncology hospital group. We analyzed preoperative clinical findings, particularly MRI imaging findings, and intraoperative information as well as the relationship between preoperative findings and outcomes.

RESULTS

Mean age was 48.9 years and the mean follow-up was 51.8 months. Prior to surgery, needle biopsy was performed on 27 patients and open biopsy on 14. T2-weighted images showed a high signal intensity in 24 patients and heterogeneous signal intensity in 20. Tumours had polylobular contours in 17 patients and smooth and round contours in 27. Collateral feeding vessels were detected in 22 patients. Gd-enhanced MRI was performed on 23 patients, and showed 15 with homogeneous enhancement and 8 with heterogeneous enhancement. Surgical times were significantly longer in patients with a retroperitoneal origin, a tumour of 10 cm or more, and polylobular-type tumours. Intraoperative blood loss was significantly greater in patients with a retroperitoneal origin and heterogeneous Gd-MRI-enhanced tumours. In histopathological evaluations, surgical margins were positive in 12 patients. Local recurrence was observed in one patient. Distant metastasis was noted in eight patients, four of whom had pulmonary metastases. Positive surgical margins were more common in polylobular-type tumours. Distant metastases were more likely to appear in patients with observable collateral feeding vessels and heterogeneous Gd-MRI enhancement.

CONCLUSION

The present results suggest that preoperative clinical findings in SFT patients predict longer surgical times and the risk of increased intraoperative blood loss. Moreover, the risk of a positive surgical margin and postoperative distant metastases may be predicted based on preoperative MRI.

Solitary fibrous tumor developing in the right retroperitoneal space

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor that is quite aggressive and prone to recurrence and metastasis. Most SFTs are benign, but the identification of the histological features that define the dedifferentiation of SFTs can predict the aggressiveness of the tumor and the presence of a reserved prognosis. We present a rare case of conventional SFTs with features of malignancy and highlight the diagnostic and therapeutic difficulties related to this case. Computed tomography aspect suggested a possible gastrointestinal stromal tumor. Surgical intervention was performed through median laparotomy and a tumor of approximately 15∕12 cm was found, developed from the level of the right retroperitoneal space, and pushing anteriorly the ascending colon, cecum, and terminal ileum. The immunohistochemical aspect correlated with the histopathological one suggests a SFT most likely malignant. In conclusion, the early diagnosis of SFTs is essential in establishing an appropriate treatment. Immunohistochemistry is indispensable in establishing the diagnosis of SFTs.

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.

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 of the Prostate Shown on FAPI PET/CT

ABSTRACT

Solitary fibrous tumors are fibroblast tumors that occur mainly in the peritoneum, extremities, and pleura. Here, we report the MRI, FDG PET/CT, and FAPI PET/CT findings of a rare prostate solitary fibrous tumor. A 57-year-old man was pathologically diagnosed with a solitary fibrous tumor. To detect any systemic metastases or other primary lesions, the patient underwent FDG PET/CT and FAPI PET/CT examination sequentially. Mild FDG uptake was observed in the primary prostatic lesion, but there was a significant uptake of FAPI in the prostate. This case highlighted that FAPI PET/CT may outperform FDG PET/CT in identifying solitary fibrous tumors.

A giant orbital solitary fibrous tumor treated by surgical excision: a case report and literature review

BACKGROUND

Spindle cell tumors, called solitary fibrous tumors (SFTs), are of mesenchymal origin, and can develop in the orbit. As 'intermediate malignancy' tumors, only a small percentage show malignant behavior, such as invasion of surrounding tissue.

CASE PRESENTATION

A 57-year-old woman presented with a 19-year history of a giant right orbital mass. Orbital computed tomography (CT) revealed an inhomogeneously-enhancing mass compressing and engulfing the eyeball and optic nerve. She underwent lid-sparing orbital exenteration. Microscopic characteristics and immunohistochemistry (IHC) tests were indicative of a benign SFT. No recurrence was observed at the 4-year follow-up.

CONCLUSION

Early and complete tumor resection is recommended.

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

BACKGROUND

Solitary fibrous tumors (SFT) are uncommon mesenchymal neoplasms which can arise in any anatomical location. Pleural SFTs have been most frequently documented; however, breast SFT is an exceedingly rare entity and seldom present in male breast, with only 8 previously reported cases. Recently, STAT6 immunostaining was considered to be a definitive marker of SFT, however, no case of the male breast SFT showing STAT6 positivity preoperatively has been reported.

METHODS AND RESULTS

We describe a case of breast SFT in a 73-year-old male patient with a 12-month history of a palpable breast mass. The only associated clinical symptom was bilateral gynecomastia. An ultrasound scan examination revealed an oval, well-circumscribed and hypoechoic mass with hypervascularity. A core-needle biopsy was performed, and microscopic examination with immunohistochemistry confirmed the diagnosis of SFT. He underwent a complete surgical resection with clear margins, and there were no signs of high cellularity, remarkable mitotic activity, pleomorphism, hemorrhage or necrosis.

CONCLUSION

A perioperative immunohistochemical evaluation for diffuse and intense nuclear expression of STAT6 was helpful to distinguish SFT from myofibroblastoma. We, herein, describe the first case of SFT in a male breast, confirmed by STAT6 immunostaining positivity. We also conducted a literature review of all previous cases of breast SFTs.

Mesenteric Solitary Fibrous Tumor with High Risk for Aggressive Behavior: A Case Report

A 64-year-old female presented to the emergency department (ED) with complaints of two days of intermittent fever and chills, progressively worsening back pain, and hematochezia. Initial evaluation and computer tomography (CT) imaging work up revealed a hypervascular and necrotic appearing pelvic mass, measuring 11.7 x 7.8 x 9.7 cm, closely associated with the inferior mesenteric vein (IMV) in conjunction with portal venous gas. Flexible sigmoidoscopy with biopsy was performed to identify the etiology of the lesion and revealed an ulcerated non-obstructing mass in the recto-sigmoid colon measuring 3 cm in length and involving 1/3 of lumen circumference with oozing present. Interventional radiology (IR) embolization of the feeding vessels was done pre-operatively due to high vascularity of the mass. Pathology of the mass was consistent with a malignant solitary fibrous tumor.

Multidisciplinary treatment of giant presacral solitary fibrous tumour: a case report and literature review

Solitary fibrous tumours (SFTs) usually occur at the pleura. Extrapleural sites, particularly giant extrapleural solitary fibromas, are more rarely observed in the clinic, and the clinical diagnosis and treatment of this disease is a focus of attention. Herein, the case of a 43-year-old male patient with giant presacral SFT successfully treated by open surgery, and with a final diagnosis confirmed by postoperative pathology and immunohistochemistry, is reported. The patient was followed-up regularly during 5 years after surgery, with no obvious surgical complications, and no tumour recurrence noted on pelvic magnetic resonance imaging. This case provides clinical information that may help in the diagnosis and treatment of complex SFT.

Recurrent meningeal malignant tumor: Assessment of differences in the solitary fibrous tumor/hemangiopericytoma spectrum through a case report

Solitary fibrous tumors (SFTs) are neoplasms that grow from mesenchymal fusiform cells. In the central nervous system, meninges are the common origin of these neoplasms. Although literature reports mostly SFT as benign neoplasm, malignancy data have been described in recurrences or metastatic lesions. Definitive diagnosis includes immunohistochemical profiles assessing cellular positivity for CD34, vimentin, CD99 and Bcl-2. Recent studies have demonstrated NAB2-STAT6 gene fusion as a distinct molecular feature of SFT with overexpression of the fusion protein NAB2-STAT6 in nuclei of these cells. Since several years, pathologists have grouped SFT and hemangiopericytomas (HPC) as different phenotypes of the same entity although both neoplasms do not share numerous features. This article, based on a case of a recurrent malignant SFT, aims to emphasize differences in the SFT/HPC spectrum due to the diagnostic, therapeutic and prognostic implications.

Rare magnetic resonance imaging findings of intracranial solitary fibrous tumor: A case report

RATIONALE

Solitary fibrous tumor (SFT) is a rare mesenchymal spindle cell tumor. SFT in the central nervous system (CNS) is rare. This case reports rare magnetic resonance imaging (MRI) findings of intracranial SFT (ISFT).

PATIENT CONCERNS

We report a 47-year-old female patient who was found to have weakness in her right limb with walking instability 2 months before the visit.

DIAGNOSES

Based on imaging, the provisional diagnosis was meningioma. Postsurgical histopathological diagnosis confirmed World Health Organization (WHO) grade I SFT/hemangiopericytoma (HPC).

INTERVENTIONS

The lesion was totally excised. The patient improved remarkably after the operation, without any signs of associated limb movement disorder.

OUTCOMES

No local recurrence or metastases were observed in the follow-up 3 months after the surgery.

LESSONS

Intracranial SFT is a rare mesenchymal tumor. Due to different tumor components, imaging manifestations are diverse and lack of characteristics, so preoperative diagnosis is challenging. Our case provides a rare ISFT with significantly decreased signal intensity in T2 weighted images (T2WI), which is an important supplement to the rare imaging findings of intracranial SFT.

Solitary Fibrous Tumor of the Bone Detected by FDG PET/CT

ABSTRACT

Solitary fibrous tumor as a rare mesenchymal tumor can occur in a wide variety of body sites, including serosal membranes, liver, lung, and deep soft tissues; however, primary tumor arising in bone is rarely documented. Herein, we reported the MRI, bone scan, and FDG PET/CT findings of a primary spinal solitary fibrous tumor in a 39-year-old woman.

Gamma Knife radiosurgery for a recurrent craniocervical junction solitary fibrous tumour

Spinal solitary fibrous tumour (SFT) is an uncommon tumour with few cases reported in the literature. It rarely originates at the craniocervical junction. To our knowledge, only eight cases of spinal SFT located at the craniocervical junction have been reported in the literature. We presented a patient with a craniocervical junction SFT and discussed its clinical presentation, radiological features, pathology, management and outcome. This was the first patient reported in the literature with a recurrent craniocervical junction SFT treated with Gamma Knife radiosurgery. The treatment reduced the tumour volume by more than 85% within 12 months.

Solitary fibrous tumour of lacrimal sac masquerading as lacrimal sac mucocele: a diagnostic and surgical dilemma

Swellings in medial canthal area in eye most often involve the lacrimal sac, the commonest aetiology being chronic dacryocystitis. Very rarely, there is a deviation in the routine diagnosis when the pathology comes out to be a lacrimal sac tumour. We report the case of a young man who presented with a medial canthal mass not extending above the medial canthal ligament. The clinical presentation was typical for a lacrimal sac mucocele, however on histopathological evaluation was diagnosed as a rare case of solitary fibrous tumour of lacrimal sac. We recommend radiological investigation in medial canthal masses where there is negative regurgitation on pressure over lacrimal sac area to avoid misdiagnoses.

Solitary fibrous tumor of the caruncle: a solitary location

A 78-year-old Caucasian male presented with diplopia and decreased vision in the left eye for 1 month, in addition to a painless fleshy lesion in the inner corner of the left eye for 3-month duration. His best-corrected visual acuity was 20/40 and 20/50. Slit lamp examination revealed a left medial conjunctival and caruncular lesion, measuring 6 mm by 4 mm. Histology of the excised mass showed a cellular submucosal spindle cell neoplasm without cytologic atypia and rare mitoses, immunohistologically diffusely positive for CD34 and STAT6, and negative for SMA. Based on these findings, solitary fibrous tumor was diagnosed. With the combined diagnostic power of light microscopy and immunohistochemistry, SFTs are diagnosed increasingly and more accurately in the orbit. With this first case report of a caruncular SFT, we believe that SFTs should remain on the differential for mesenchymal tumors of the conjunctiva and caruncle.

Giant cell-rich solitary fibrous tumour of the lacrimal gland with prominent angiomatoid cystic changes and an underlying NAB2ex3-STAT6ex18 fusion

Giant cell-rich solitary fibrous tumour (GCR-SFT) is a rare variant of SFT with a predilection for the orbital region. Despite its hypervascularity, extensive angiomatoid cystic changes are unusual in GCR-SFT and may pose a diagnostic challenge. A 47-year-old man presented with a right eye proptosis and a protruding tumour of several years’ duration with recently accelerated tumour growth. MRI revealed a cystic-solid heterogeneous mass arising from the lacrimal gland and displacing the globe. A subtotal excision of the mass was performed due to unanticipated hypervascularity and intraoperative bleeding. Pathologically, a vascular neoplasm was initially suspected. The diagnosis of GCR-SFT was made following careful evaluation and demonstration of CD34 and STAT6 expression. Molecular studies revealed a pathognomonic but rare NAB2ex3-STAT6ex18 fusion variant as well as a TP53 mutation suggestive of aggressive phenotype. The patient had a complete resolution of the proptosis but the clinical picture remains guarded due to incomplete resection.

The challenge to prove a rare cause of secondary arterial hypertension. A case report of a pediatric renal solitary fibrous tumor

BACKGROUND

Childhood hypertension is getting more attention in recent years. We present a case report of a rare cause of secondary arterial hypertension in a teenage girl - a solitary fibrous tumor of the kidney. The case demonstrates that standard imaging techniques, computed tomography and magnetic resonance imaging, are not fully reliable in the diagnosis of renovascular hypertension.

CASE

A 15-year old girl was admitted to the Pediatric Department because of episodes of stiffness in the limbs, accompanied by pale skin and lips, dated 4 months back. During these episodes, high blood pressure up to 160/100 mmHg was measured. A 24-hour blood pressure monitoring demonstrated arterial hypertension stage II. Renovascular hypertension was suspected, but the computed tomography examination of the abdomen showed normal-sized renal arteries. In the left kidney hilum, an intraparenchymal formation was discovered. The data presented a non-specific lesion with a wide differential diagnosis. Given the fact that the patient had been treated with an ACE-inhibitor, serum renin level could not be correctly interpreted. The lesion was removed through a laparoscopic intervention. Intraoperatively, the tumor was compressing a small intra-renal vessel - a finding that hadn`t been discovered by the previous imaging studies. The final pathologist diagnosis was: solitary fibrous tumor. During the next six months of follow-up, the maximal blood pressure values of the patient were up to 120/80 mmHg.

CONCLUSIONS

Solitary fibrous tumors of the kidneys are infrequent in children. The presented case displays a rare form of initial clinical manifestation of this tumor. It is also a demonstration that standard imaging techniques are not able to get a precise visualization of the small intra-renal vessels. At the same time, the decision of whether or not to perform a more invasive procedure should be based on the clinical conditions and risks of the individual patient.

Solitary Fibrous Tumor of Adrenal Gland and Review of the Literature

Solitary fibrous tumor (SFT) is a rare and still controversial entity. This type of tumor first appeared in the literature as a pleural lesion, but, over the last decades, it has been reported in many extrathoracic sites. As a tumor of the adrenal gland, SFT is still rare and very uncommon, thus extensive research among the English language literature has been performed. We present here a case report of an adrenal SFT which is compared to 11 other known cases. Our case report is from a patient with SFT on the left adrenal gland, followed by mild symptoms of abdominal discomfort and hypertension. Physical examination, laboratory, and radiological tests were performed. The patient underwent surgery and the material was sent for histopathologic analysis for a definite diagnosis. Regular follow up appointments were performed over the course of two years. No recurrence of the tumor has been detected. We explain the symptoms, diagnosis, treatment, and additionally we describe the results and implications of the findings reported in the literature. Correct diagnosis is mandatory for optimal management of solitary fibrous tumor patients.

Solitary Fibrous Tumor of the Prostate: A Case Report and Literature Review

Solitary fibrous tumors (SFTs) usually occur in the pleura and account for two-thirds of all cases; however, SFTs occurring in the prostate are extremely rare. Approximately 25 cases have been reported in the literature to date. This study reports the case of a 43-year-old man referred to our hospital with the chief complaint of a pelvic tumor after careful examination. The tumor marker levels were within normal limits. T2-weighted magnetic resonance imaging revealed a tumor, demonstrating primarily low signal intensity. It showed a capsule-like rim at the left lobe of the prostate, suggesting that the tumor was partially invading the rectal wall. Histopathological examination of needle-core biopsies showed spindle cell neoplasm with small and fusiform cells, strongly expressing signal transducer and activator of transcription 6 (STAT6) with a ramifying vascular network. Therefore, the clinical diagnosis of the patient was SFT of the prostate and robot-assisted radical prostatectomy was performed. Histopathological examination revealed that the tumor was composed of spindle cells with patternless and staghorn patterns. Immunohistochemical analysis showed a strong expression of STAT6. Furthermore, the tumor was partially positive for CD34. Therefore, the patient was diagnosed with SFT of the prostate. Two years after the initial diagnosis, the patient was alive with normal erectile function, continence status, and no evidence of the disease.

A rare case of rectal bleeding and Fusobacterium mortiferum sepsis due to solitary fibrous tumour originating from the mesentery

Solitary fibrous tumours (SFTs) are rare mesenchymal tumours that are mostly seen in the pleura. Lately, they have also been described in other locations. Recent discovery of the NAB2-STAT6 fusion gene which is specific for SFTs has led to an accurate diagnosis of SFTs. The occurrence of SFTs in the mesentery is very rarely reported in the literature. We report a case of a 63-year-old female who presented with abdominal pain, rectal bleeding and Fusobacterium bacteraemia, who was ultimately found to have a mesenteric SFT.

A Rare Case of Metastatic Solitary Fibrous Tumor (Hemangiopericytoma) of the Dura on 18F-FDG PET/CT

ABSTRACT

Solitary fibrous tumor is a rare neoplasm of mesenchymal origin. It can arise in various locations, most commonly in the pleura. It encompasses a heterogeneous group of histological patterns with different biological behavior. In some cases, metastases occur, sometimes years after the initial diagnosis. We report a case of metastatic meningeal hemangiopericytoma, also called solitary fibrous tumor of the dura, exhibiting liver metastases and muscle metastases 5 years after resection and adjuvant radiotherapy of the primary tumor.

Doege-Potter syndrome: a systematic review of the literature and case presentation of a rare pelvic malignant solitary fibrous tumour

Solitary fibrous tumours (SFTs) are a rare mesenchymal neoplasm with an incidence of 2.8 per 100 000 of which only 1% occur in the female genital tract. Doege-Potter syndrome is a paraneoplastic phenomenon associated with approximately 5%-10% of SFTs and is characterised by non-islet cell hypoglycaemia due to tumour production of low molecular weight insulin-like growth factor-II. We present the fourth confirmed case of female pelvic SFT with Doege-Potter syndrome and a literature review.