Solitary fibrous tumor of the prostate: 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.

Solitary fibrous tumor is an extremely rare clinical entity, most commonly manifested in the pleura and peritoneum. An increasing number of cases are found to occur at extrapleural sites. We report a case of solitary fibrous tumor arising from the mesentery of the small intestine. A 53-year-old man presented with a large abdominal mass which was initially thought to be a gastrointestinal stromal tumor. The tumor was successfully removed surgically and the diagnosis of solitary fibrous tumor was confirmed on immunohistochemical analysis. To our knowledge this is the first reported case of a solitary fibrous tumor arising from the small bowel mesentery.

OBJECTIVE AND IMPORTANCE: A solitary fibrous tumor (SFT) is a rare neoplasm of probable mesenchymal origin that was first reported in the pleura but can occur in different sites. Only six cases of SFT arising from the spinal cord have been reported. CLINICAL PRESENTATION: We report a case of primary SFT occurring in the thoracic spinal cord in a 64-year-old man with Brown-Séquard syndrome. Magnetic resonance imaging revealed an intradural mass at the level of T2–T3. INTERVENTION: Total T2–T3 laminectomies were performed. The tumor appeared to be adherent to the right lateral aspect of the cord but not attached to the meninges. On histological examination, the tumor exhibited spindle cell proliferation with abundant dense collagen but without a hemangiopericytomatous pattern. Immunohistochemically, the tumor cells were reactive with CD34 and vimentin only. CONCLUSION: We report a rare case of SFT occurring in the thoracic spinal cord. Histologically and immunohistochemically, we confirmed the diagnosis of SFT. Low signal intensity on T1- and T2-weighted images corresponded to the histological findings. When a spinal cord tumor exhibits a signal pattern similar to this, SFT should be included in the differential diagnosis. Because of the rarity of reports on this condition, the clinical manifestations and course of SFT of the spinal cord are unknown, and careful long-term follow-up is recommended.

Solitary fibrous tumors (SFT) are rare mesenchymal neoplasms. They were first described as spindle-cell tumors originating from the pleura, but they may arise in any anatomical site. SFT of the breast is an exceedingly rare clinical entity. Our literature review yielded only 21 cases reported so far. We describe a case of a SFT of the breast in a premenopausal patient who presented with a gradually enlarging palpable breast mass. Diagnostic evaluation and management are discussed along with a review of the relevant literature. There are no pathognomonic imaging findings of SFT of the breast. Complete surgical resection with clear margins is the gold standard of treatment. Thorough immunohistochemical analysis is crucial to obtain a definitive diagnosis. Although most SFTs run an indolent course, in some cases the clinical behavior can be unpredictable and a long-term follow-up for all patients is therefore mandatory.

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms of fibroblastic origin that mainly arise from the pleura. Although SFTs arising at numerous extrapleural locations have been reported, extrapleural soft tissue SFTs are extremely rare. The diagnosis of SFTs is based on histologic findings. However, given the histological variability of SFTs, immunohistochemical examination becomes important in their diagnosis. Complete surgical resection is the only and a very important prognostic factor and is recommended for the treatment of both benign and malignant SFTs with a curative intent. Here, the author reports what he believes to be the first case of an SFT originating in the mons pubis.

OBJECTIVE AND IMPORTANCE Solitary fibrous tumors (SFTs) are rare tumors of mesenchymal origin that typically arise in the pleura. Only 24 cases of SFTs in the orbit have been reported, all located within the orbit and generally with a benign course. We report the first case of an orbital SFT with extraorbital extension and short-term regrowth. CLINICAL PRESENTATION A 54-year-old man presented with proptosis and double vision that had persisted for 7 months. The tumor extended from the right extraconal inferolateral orbit to the extradural middle cranial fossa and cavernous sinus, via the superior orbital fissure, on magnetic resonance imaging scans. Positron emission tomography with [18F]fluorodeoxyglucose demonstrated faint uptake in the orbital portion. INTERVENTION Resection of the tumor was performed twice, because of short-term regrowth of the residual tumor in the orbit. The histological diagnosis was a SFT. The MIB-1 labeling index was 7% and the mitotic count was 5 mitotic figures/10 high-power fields at the time of the second operation. These findings indicate the malignant nature of the tumor. CONCLUSION The natural history of SFTs of the orbit remains unclear, and the importance of careful and continued follow-up monitoring of the tumor should be emphasized.

Solitary fibrous tumor involving the pancreas: report of the cytologic features and first report of a primary pancreatic solitary fibrous tumor diagnosed by fine-needle aspiration biopsy

Introduction Solitary fibrous tumors (SFT) are typically characterized by the proliferation of CD34-positive specialized fibroblasts. While these tumors are most found in the pleura, they can also present in extra-pleural sites, including the orbit, particularly in adults. Herein, we report a rare case of SFT of the eyelid in a pediatric patient and review the existing literature on similar cases. Methods A case of a 5-year-old male with a nodule on the eyelid margin is presented. The nodule was completely resected and histopathologically confirmed as SFT. A comprehensive review of the published cases of eyelid SFT was conducted. Results The case represents the second reported instance of eyelid SFT in a pediatric patient and is the youngest case documented to date. The tumor’s histopathological examination revealed characteristics consistent with SFT. The review of the literature identified only 10 cases of eyelid SFT in English literature, with just one previously reported in the pediatric population. Conclusion SFT of the eyelid is extremely rare, especially in pediatric patients. Despite its rarity, SFT should be considered in the differential diagnosis of vascular spindle-cell tumors of the eyelid in this age group. Early recognition and complete resection are crucial for effective management.

Central nervous system solitary fibrous tumors are a new pathological entity. To our knowledge, only 60 meningeal solitary fibrous tumors both in the spinal cord and in the brain have been described in the literature. The 56 previously reported cases of meningeal solitary fibrous tumors are critically reviewed. In addition, we report four new cases of solitary fibrous tumors of the meninges. There is a slight male prepoderance. Meningeal solitary fibrous tumors show a tendency to arise in the posterior fossa (26%) and spine (25%). The treatment was mainly total surgical excision. Radiotherapy was given only to four patients with tumors involving the cerebral parenchyma. Sporadic cases of recurrence and distant metastasis have been reported. The prognosis of meningeal solitary fibrous tumors is still unknown because the follow-up of the reported cases is short. It is probable that cases of solitary fibrous tumors of the meninges have been misdiagnosed as other tumors in the past. The best management of these tumors seems to be total surgical excision whenever possible. It is important that every new case of meningeal SFT be reported to throw light on this particular tumor and to affirm its status as a clinicopathological entity.

A solitary fibrous tumor is a relatively uncommon neoplasm that usually occurs in the pleura but occurs extremely rarely in the oral cavity. Reported herein is a rare case of a solitary fibrous tumor in the buccal cheek mucosa. A 50-year-old man visited the authors' hospital due to a buccal cheek mass whose size had increased. Excisional biopsy was done under local anesthesia. After the excisional biopsy, the patient was diagnosed to have a solitary fibrous tumor. In immunohistochemistry, the patient's solitary fibrous tumor was characterized by the expression of CD34 and CD99 on the neoplastic cells, and negativity for Bcl-2 and S-100. No recurrence or complication occurred for a period of 5 years. The growth of a primary solitary fibrous tumor in the buccal cheek mucosa is extremely rare and has been rarely reported in the South Korean medical literature. A solitary fibrous tumor must be distinguished from other spindle cell tumors. Presented herein is a case of primary solitary fibrous tumor in the buccal cheek mucosa. The relevant literature is briefly reviewed.

Purpose: To describe the first confirmed case of solitary fibrous tumor in Saudi Arabia and in the Middle East, and to illustrate a surgical technique for atraumatic complete removal. Methods: A retrospective interventional case report that describes the first confirmed case of solitary fibrous tumor in the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia. Results: The clinical presentation, computed tomography (CT) findings, and histopathological, immunohistochemical and electron microscopic findings to confirm the diagnosis, as well as the cryodissection surgical technique for atraumatic removal of solitary fibrous tumor used, are described. Conclusions: Solitary fibrous tumor should be considered in the differential diagnosis when a patient presents with unilateral proptosis and a well-circumscribed, intensely enhancing mass on CT imaging. Because of the risk of malignant transformation, surgical en bloc removal with minimal tissue damage is the treatment of choice. This may be achieved by means of cryo-extraction via a minimally invasive orbitotomy.

BackgroundSolitary 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 presentationWe 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.ConclusionGenital 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.

ObjectiveSolitary fibrous tumor (SFT) is a very rare tumor. The purpose of this study is to determine the MR imaging features of SFT in the intracranial and extracranial head and neck regions.Materials and MethodsWe retrospectively reviewed six MR images and two CT images of six histologically proven cases of SFT that occurred in four men and two women, and their ages ranged from 46 to 59 years. These imaging findings were correlated with the microscopic findings of their surgical specimens.ResultsSix SFTs arose in the meninges (the petrous ridge and the pituitary fossa), the parotid gland, the parapharyngeal space, the buccal space and the maxillary sinus. On the MR images, SFTs in the intracranial and extracranial head and neck regions were mostly isointense to the muscle on the T1-weighted images, they were hyperintense on the T2-weighted images and they all had intense enhancement. On the T1- and T2-weighted images, hypointense lines were observed within in five SFTs. On the CT images, the SFTs were hypodense to the muscle on the unenhanced images and they were heterogeneously enhanced on the contrast-enhanced images. An exceptional case of pituitary SFT was hypointense on the T2-weighted images and it was hyperdense on the unenhanced CT images, which correlated with the increased collagenous component and the cellular compactness.ConclusionThe imaging features of SFT are nonspecific; however, SFT should be included in the differential diagnosis of masses involving the intracranial and extracranial head and neck regions.

Solitary fibrous tumor of the orbit: a clinicopathologic study of six cases with review of the literature

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms, displaying variable morphological and clinicopathological features. Supportive immunohistochemical markers such as CD34, CD99, BCL2 and LSD1 are commonly applied in the differential diagnosis of SFTs, although none is sufficiently sensitive or specific enough. The aim of the present study was to examine the most differential markers for the reliable distinction of SFTs from histological mimics. We investigated the expression of STAT6, NAB2, ALDH1, GRIA2 and IGF2 in 454 comprehensive soft tissue tumors, comprising formalin-fixed paraffin-embedded (FFPE) tissue samples from 80 SFTs and 374 other mesenchymal tumors. The Duolink in situ proximity ligation assay (PLA) was adopted for the detection of NAB2-STAT6 fusion proteins. STAT6 was expressed in all 80 SFT cases with a moderate-strong nuclear staining intensity. In contrast, only 4/374 (1%) non-SFT mesenchymal tumors showed a nuclear STAT6 staining pattern. Strong expression of NAB2 and IGF2 was detected in SFT and non-SFT cases. Positive GRIA2 immunoreactivity was found in 64% (SFT) and 8% (non-SFT), respectively. Expression of ALDH1 was moderate-strong in 76% (SFT), whereas only 2 non-SFT lesions showed positive ALDH1 immunoreactivity. Moreover, the presence of NAB2‑STAT6 fusion proteins was indicated in 71/78 (91%) SFT cases by PLA. Nuclear STAT6 and cytoplasmic ALDH1 expression are the most sensitive and specific markers in the differential diagnosis of SFTs. Furthermore, application of Duolink in situ proximity ligation assay can be helpful to detect the NAB2-STAT6 fusion protein in the majority of SFTs.