Benign Solitary Fibrous Tumor Research Articles

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

BackgroundSpindle 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 presentationA 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.ConclusionEarly and complete tumor resection is recommended.

IGF-2 mediated hypoglycemia and the paradox of an apparently benign lesion: a case report & review of the literature

BackgroundNon-islet cell tumour hypoglycemia (NICTH) is rarely encountered in clinical practice. Insulin-like growth factor 2 (IGF2) is the most common cause of NICTH observed in the setting of mesenchymal and epithelial neoplasia. This is a paraneoplastic syndrome caused by IGF2 activation of the insulin receptor.Case presentationAn 80 year old female presented with a short history of recurrent episodes of confusion with laboratory confirmed hypoglycemia with a plasma glucose of 2.7 mmol/L on fasting which fulfilled Whipple’s triad. Diagnostic clues to the aetiology at presentation include the fasting pattern of hypoglycemia, hypokalaemia and the absence of weight gain. A 72 hour fast with results showed early hypoglycemia and suppression of serum insulin, c-peptide, and proinsulin. Serum insulin antibody was not detected. Subsequent measurement of the serum IGF2:IGF1 ratio was elevated at 22.3 and consistent with IGF-2 mediated hypoglycemia and imaging studies demonstrated a pelvic mass. Dietary intervention and oral prednisolone abated hypoglycemia prior to surgery. Ultimately, hypoglycemia resolved following operative intervention and steroid therapy was successfully withdrawn. Histopathology was remarkable for dual neoplastic processes with uterine solitary fibrous tumour (SFT) confirmed as the source of IGF2 hypersecretion on IGF-2 immunohistochemistry and a coincidental invasive high grade serous carcinoma involving the fimbria of the right fallopian tube.ConclusionThe paradox in this case is that the benign solitary fibrous tumour accounted for patient morbidity through secretion of IGF2 and without treatment, posed a mortality risk. This is despite the synchronous presence of a highly malignant fallopian tube neoplasm. This case reinforces the need for thorough clinical evaluation of hypoglycemia to allow prompt and definitive management.

Novel Therapeutic Options for Solitary Fibrous Tumor: Antiangiogenic Therapy and Beyond.

Simple SummaryIn the latest WHO classification, solitary fibrous tumors (SFTs) are now subdivided into benign SFT (intermediate category (locally aggressive)), SFT NOS (intermediate category (rarely metastasizing)), and malignant SFT. Thanks to recent progress in molecular characterization, the identification of the NAB2–STAT6 fusion oncogene has emerged as a specific cytogenetic hallmark for SFT. Despite these recent advances in classification and understanding of the molecular pathophysiology of SFT, there are no consensus clinical guidelines regarding systemic treatment. Several new therapeutic options are of interest in this subtype of sarcoma considered as refractory to classical chemotherapy. In case of advanced disease, antiangiogenic therapy might be viewed as the best therapeutic option.SFT is an ultrarare mesenchymal ubiquitous tumor, with an incidence rate <1 case/million people/year. The fifth WHO classification published in April 2020 subdivided SFT into three categories: benign (locally aggressive), NOS (rarely metastasizing), and malignant. Recurrence can occur in up to 10–40% of localized SFTs, and several risk stratification models have been proposed to predict the individual risk of metastatic relapse. The Demicco model is the most widely used and is based on age at presentation, tumor size, and mitotic count. Total en bloc resection is the standard treatment of patients with a localized SFT; in case of advanced disease, the clinical efficacy of conventional chemotherapy remains poor. In this review, we discuss new insights into the biology and the treatment of patients with SFT. NAB2–STAT6 oncogenic fusion, which is the pathognomonic hallmark of SFT, is supposedly involved in the overexpression of vascular endothelial growth factor (VEGF). These specific biological features encouraged the successful assessment of antiangiogenic drugs. Overall, antiangiogenic therapies showed a significant activity toward SFT in the advanced/metastatic setting. Nevertheless, these promising results warrant additional investigation to be validated, including randomized phase III trials and biological translational analysis, to understand and predict mechanisms of efficacy and resistance. While the therapeutic potential of immunotherapy remains elusive, the use of antiangiogenics as first-line treatment should be considered.

Hypoglossal Nerve Palsy As an Initial Presentation of Glomus Jugulare Tumor in Patient with Breast Cancer: A Case Report and Literature Review

Background: Glomus jugulare tumor is a rare, slow-growing, hyper-vascular paraganglioma that originates from the neural crest derivatives in the wall of the jugular bulb. The most common clinical manifestations of glomus jugulare are pulsatile tinnitus, conductive hearing loss, and hoarseness due to its vascularity and invasion of surrounding structures. Isolated hypoglossal nerve palsy as a presenting feature of the glomus jugulare is very rare. Case Report: We report a 61-year-old woman with a past medical history of breast cancer and diabetic mellitus presenting with progressive difficulty handling food in her mouth and tongue atrophy. Investigations showed skull base lesion and solitary pulmonary nodule. Further work-up led to glomus jugulare and benign solitary pulmonary fibrous tumor diagnosis, although the first impression was metastatic involvement of the jugular foramen. Endovascular embolization of the glomus jugulare was performed, but the patient refused any open surgery due to co-morbidities and the risk of operation. She had no new symptoms at the one-year follow-up, and the size of the lesion became more minor on the follow-up imaging relative to the baseline. Conclusion: Glomus jugulare tumors should be considered and surveyed in the diagnostic work-up of patients with hypoglossal nerve palsy. [GMJ.2021;10:e2222]

Hypoglossal Nerve Palsy As an Initial Presentation of Glomus Jugulare Tumor in Patient with Breast Cancer: A Case Report and Literature Review

Background: Glomus jugulare tumor is a rare, slow-growing, hyper-vascular paraganglioma that originates from the neural crest derivatives in the wall of the jugular bulb. The most common clinical manifestations of glomus jugulare are pulsatile tinnitus, conductive hearing loss, and hoarseness due to its vascularity and invasion of surrounding structures. Isolated hypoglossal nerve palsy as a presenting feature of the glomus jugulare is very rare. Case Report: We report a 61-year-old woman with a past medical history of breast cancer and diabetic mellitus presenting with progressive difficulty handling food in her mouth and tongue atrophy. Investigations showed skull base lesion and solitary pulmonary nodule. Further work-up led to glomus jugulare and benign solitary pulmonary fibrous tumor diagnosis, although the first impression was metastatic involvement of the jugular foramen. Endovascular embolization of the glomus jugulare was performed, but the patient refused any open surgery due to co-morbidities and the risk of operation. She had no new symptoms at the one-year follow-up, and the size of the lesion became more minor on the follow-up imaging relative to the baseline. Conclusion: Glomus jugulare tumors should be considered and surveyed in the diagnostic work-up of patients with hypoglossal nerve palsy. [GMJ.2021;10:e2222]

Intrathoracic giant solitary fibrous tumor of the pleura: Case report

IntroductionSolitary Fibrous Tumor of the Pleura(SFTP) is exceedingly rare mesenchymal tumor commonly arising from the visceral pleura and accounts for <5% of all pleural tumors. Although it commonly has benign histologic characteristics, the tumor behavior is often unpredictable and less understood due to limited number of cases.Case presentationWe present a rare case of Intrathoracic Giant SFTP in a 65 years old female who presented with a progressive worsening of shortness of breath of 1 year duration associated with intermittent dry cough, low grade fever, easy fatigability and loss of appetite. Complete enbloc resection was done and she was discharged improved.DiscussionMost patients with SFTP are asymptomatic and definitive diagnosis is often made after surgical exploration and histopathologic study. Although 80% of SFTP arise from visceral pleura, the origin in our case was from the parietal pleura which is rare.ConclusionSFTP should be considered as differential diagnosis in patients with atypical or recurrent respiratory symptoms despite adequate medical treatment. Complete surgical excision is the main stay of treatment and meticulous post-operative follow up is mandatory as the risk of recurrence is higher and the tumor behavior is still less understood.

Bilateral Orthotopic Lung Transplantation after Resection of Benign Solitary Fibrous Tumor in the Donor Lung

IntroductionSolitary fibrous tumor (SFT) of the pleura is a rare soft tissue tumor of mesenchymal origin. Transplantation of donor lung with SFT has not been reported in the literature. We report the first case of a bilateral orthotopic lung transplantation utilizing donor lung which had SFT in the left lung.Case ReportThe donor was a brain dead 25 year old male who suffered from subarachnoid hemorrhage. He had no other comorbidities. The recipient is a 59 year old male with end stage fibrosing interstitial lung disease consistent with usual interstitial pneumonia (UIP) who was listed for bilateral orthotopic lung transplantation. His other comorbidities included triple vessel coronary artery disease, hypertension and type 2 diabetes mellitus. During the lung harvest, it was noted that the left lung had a circumferential 1 centimeter reddish appearing nodule in the left upper lobe. A stapled wedge resection of this nodule was performed during back table dissection. Pathology showed benign solitary fibrous tumor with 1 centimeter negative margins. The recipient underwent BOLT and 3 vessel coronary artery bypass grafting (CABG) on cardiopulmonary bypass via a thoracosternotomy (Clamshell). Post-operative course was uneventful and the patient was discharged home on post operative day 15. He continues to do well and symptom free at 1 year follow up. He underwent chest computed tomography (CT) scan 6 months and 1 year and there were no lung lesions identified.SummaryBilateral Orthotopic Lung Transplantation can be successfully be performed when utilizing donor lungs with benign tumors like solitary fibrous tumor. Regular follow up with CT scans is a necessary surveillance study to ensure there is no tumor recurrence. Solitary fibrous tumor (SFT) of the pleura is a rare soft tissue tumor of mesenchymal origin. Transplantation of donor lung with SFT has not been reported in the literature. We report the first case of a bilateral orthotopic lung transplantation utilizing donor lung which had SFT in the left lung. The donor was a brain dead 25 year old male who suffered from subarachnoid hemorrhage. He had no other comorbidities. The recipient is a 59 year old male with end stage fibrosing interstitial lung disease consistent with usual interstitial pneumonia (UIP) who was listed for bilateral orthotopic lung transplantation. His other comorbidities included triple vessel coronary artery disease, hypertension and type 2 diabetes mellitus. During the lung harvest, it was noted that the left lung had a circumferential 1 centimeter reddish appearing nodule in the left upper lobe. A stapled wedge resection of this nodule was performed during back table dissection. Pathology showed benign solitary fibrous tumor with 1 centimeter negative margins. The recipient underwent BOLT and 3 vessel coronary artery bypass grafting (CABG) on cardiopulmonary bypass via a thoracosternotomy (Clamshell). Post-operative course was uneventful and the patient was discharged home on post operative day 15. He continues to do well and symptom free at 1 year follow up. He underwent chest computed tomography (CT) scan 6 months and 1 year and there were no lung lesions identified. Bilateral Orthotopic Lung Transplantation can be successfully be performed when utilizing donor lungs with benign tumors like solitary fibrous tumor. Regular follow up with CT scans is a necessary surveillance study to ensure there is no tumor recurrence.

Refractory hypoglycemia associated with giant solitary fibrous tumor of the pleura (Doege–Potter syndrome)

The association of a solitary tumor of the pleura with paraneoplastic refractory hypoglycemia is a very rare clinical condition. An 86-year-old gentleman with an incidentally discovered large mass in the left chest and a long-standing history of refractory hypoglycemia was referred for surgical consultation. Computed tomography and PET (Positron Emission Tomography) scan confirmed the presence of a homogeneous mass leaning on the left hemidiaphragm with no tracer uptake. After tumor board discussion, the mass was radically excised through a left thoracotomy. Histopathology revealed a benign solitary fibrous tumor of the pleura. At 1‑year follow-up the patient was doing well and did not further complain of hypoglycemia-related symptoms. Doege–Potter syndrome is a life-threatening condition associated with severely impaired quality of life. Prompt identification and surgical treatment are mandatory.

Clinical management of extrapleural septal solitary fibrous tumor: A case report.

Solitary fibrous tumor (SFT) is a rare neoplasm arising from the pleura, although it can sometimes affect extrapleural sites, including the head and neck. The sinonasal involvement is exceptional. Recent literature defines the SFT as a single spectrum of mesenchymal tumors, including hemangiopericytoma, which is currently considered a cellular phenotypic variant. The current case describes a rare case of a nasal septal SFT. The mass was embolized and then removed through endonasal endoscopic surgery. Histopathologic examination demonstrated positive immunoreactivity for CD34, and negative for keratin and S100 protein confirming the diagnosis of benign nasal SFT. After two years of follow-up, no relapse was observed. Diagnostic assessment of SFT requires nasal endoscopy, imaging and histopathological examination and a long time follow up is mandatory.

Malignant SFT with nodal metastasis, a case report

Solitary fibrous tumours (SFT) are generally rare neoplasms. These tumours were first described in the pleura and later appeared to involve almost every organ. They affect all ages with no sex predilection. Most of the pleural lesions are discovered incidentally. The majority of these tumours are benign with 13–25% considered malignant. Microscopically the tumours are cellular and consist of fibroblastic spindle cells in a pattern-less pattern with a variable amount of hemangiopericytoma like vascular spaces and stromal hyalinisation. The lesions are positive for CD34, BCL2, CD99 and STAT6. Malignant SFTs are differentiated from benign SFTs by hypercellularity, pleomorphism, necrosis and mitosis of more than 4/10 HPFs. In this case report, we present a patient who presented to their GP with back pain and during workup was found to have a right lower lobe lung mass. A lobectomy was performed and the tumour was found to be a malignant pleural based SFT with metastasis to a single peri-hilar lymph node. Seventeen months later, the patient presented with a secondary metastatic nodule with features similar to the primary lung tumour. At this stage, the patient was considered unamenable to further surgery or curative radiotherapy.

Solitary fibrous tumour of the oral cavity: An update.

Solitary fibrous tumour is an unusual neoplasm of the oral cavity that is sometimes not clinically distinguishable from other lesions. The purpose of the present study was to review the clinical, microscopic and molecular aspects of malignant and benign solitary fibrous tumour of the oral cavity currently available in literature. For our review, an electronic search was performed using PubMed, Scopus, Ovid/MedLine, Web of science and ProQuest Dissertations and Theses Global database. A total of 74 publications reporting 150 cases were included. Oral solitary fibrous tumours are most frequently described as submucosal, well-circumscribed, asymptomatic nodule, more prevalent in females in their fourth to fifth decades of life. Buccal mucosa is the most commonly affected site by the benign tumour variant, whereas the tongue is the most common location affected by the malignant form of the neoplasm. Most of the lesions were treated by conservative surgery. One recurrent malignant tumour and one metastasis are reported. Asymptomatic normal-coloured submucosal nodules located in the buccal mucosa and tongue in adult patients are suggestive of oral solitary fibrous tumour, but only a careful microscopic examination can differentiate benign from malignant variants and the use of immunohistochemistry (CD34, Bcl-2, CD99 and STAT6), and cytogenetic studies (NAB2-STAT6) contribute significantly to confirm the diagnosis of solitary fibrous tumour in difficult cases.

Clinicopathological characteristics of renal solitary fibrous tumor: A single institution experience.

To analyze the clinical characteristics, treatment modalities and outcomes of adult renal solitary fibrous tumors (SFT) treated at a single institution. Demographic, diagnostic, surgical, and pathological findings of patients who had undergone radical nephrectomy (RN) due to renal SFT were collected from the database of a single institution and were retrospectively reviewed. Ten patients (6 men and 4 women) were diagnosed with renal SFT in our institution between January 1, 2000 and December 31, 2016. The mean age was 50.9 ± 8.2 years (range, 38–63 years). Of the 10 patients, 6 were asymptomatic, 2 presented with flank pain, 1 presented with abdominal discomfort, and 1 presented with haematuria. Computed tomography scans were obtained for all patients. Open RN was performed on 6 patients, and laparoscopic RN was performed on 4 patients. The mean tumor size was 10.23 ± 4 cm (range, 5.3–19 cm). Pathological diagnosis revealed that the tumors in 8 patients were benign, while those in the other 2 patients were malignant renal SFT. No recurrence occurred during a mean follow-up period of 47.3 ± 21.5 months (range, 16–85 months). Renal SFT is extremely rare, and its diagnosis may be challenging because of a lack of typical imaging manifestations. RN is a safe treatment modality for benign or low-grade malignant renal SFT, ensuring favorable outcomes.

Solitary Fibrous Tumor of the Dorsal Tongue Area.

Solitary fibrous tumor (SFT) is a rare tumor occurring in pleura or extrapleural areas. The tongue is infrequently affected, in less than 25 published cases. A female patient, 35years of age, noticed an oval mass in the posterior dorsal part of the tongue. The operated mass was nodule, 10mm in size, sharply circumscribed, rather firm. The histology shows uniform CD34 positive spindle tumor cells. The diagnosis of benign SFT of the tongue was made.

Solitary fibrous tumour of the spine: imaging features of a commonly misdiagnosed entity.

Solitary fibrous tumours (SFTs) occurring in the spine are rare. Herein, we review the clinical and imaging data of spinal SFT. We retrospectively analysed eight cases of pathologically confirmed spinal SFT imaging and clinical data, pathological manifestations, surgical methods, and follow-up results. Five SFTs cases occurred in the cervical spine, two in the thoracic spine, and one in the lumbosacral spine. Five cases showed a dumbbell-shaped or lobulated soft tissue mass that grew across the intervertebral foramen, two cases showed an expansive intraosseous mass formation in the vertebral body and/or posterior element, and one case showed a long-spindle shaped intraspinal canal mass growing along the spinal canal. Seven caused local invasion and destruction of the vertebral body and posterior element. Benign SFTs displayed a good prognosis, whereas malignant SFTs were prone to recurrence and metastasis (3/4). Spinal SFTs are difficult to characterise with imaging and required pathological and immunohistochemical investigation. Prolonged follow-up is recommended once a diagnosis of spinal SFTs has been established because of the unclear biology. • Spinal solitary fibrous tumours are extremely rare. • SFTs should be showed the differential of masses developing though the foramen. • Combing imaging with pathology and immunochemistry assesses the diagnosis and establish nature.

Unedited microneurosurgery of a solitary fibrous tumor of the pineal region.

Background:Solitary fibrous tumor/hemangiopericytoma is a new combined entity introduced in the 2016 World Health Organization classification of tumors of the central nervous system for grade I–III soft-tissue tumors. While grades II and III present more aggressive course and might require adjuvant radiochemotherapy, grade I tumors have a good outcome after gross total resection. In this video-abstract, we present an unedited microneurosurgery of a histologically confirmed benign solitary fibrous tumor of the pineal region performed by a senior author (JH). Our aim is to demonstrate the efficiency and safety of our microsurgical technique into deep brain territories under the principle “simple, clean, and preserving the normal anatomy.” For this, a paramedian supracerebellar infratentorial approach and a proper praying sitting position are essential.Case Description:A patient with a history of slow progressive hydrocephalus was placed in a sitting praying position. The pineal region was accessed over the right cerebellar hemisphere following a right paramedian supracerebellar infratentorial approach. The lesion identified after a lateral opening of the quadrigeminal cistern followed partial debulking. Small vessels running on the surface of the tumor were coagulated and cut. After a careful dissection and devascularization of the lesion, the tumor was pulled out using long ring microforceps and long sharp bipolar forceps as well. The final steps included detachment of some tumoral remnants from the internal cerebral veins and meticulous attention to any bleeding securing complete hemostasis of the surgical site. The postoperative course was uneventful with only slight and occasionally double vision. The patient is alive and free of recurrence almost 4 years after surgery.Conclusion:This unedited video offers all detailed aspects that a neurosurgeon like senior author JH considers essential when performing an efficient and safe surgery into the pineal region for this very rarely documented solitary fibrous tumor.Videolink:http://surgicalneurologyint.com/videogallery/pineal-tumor

The Peculiar Case of a Large Right Lower Quadrant Solitary Fibrous Tumor With Vasculature Arising from the Splenic Artery and Vein

We present the interesting case of a patient with peritoneal solitary fibrous tumor (SFT). The patient initially presented with right lower quadrant pain. Computed tomography findings revealed the presence of a large mass near the cecum, with both arterial and venous blood supply arising directly from the splenic artery and vein. The patient ultimately underwent surgical excision of the mass, and pathological examination was consistent with benign SFT. Not only is the location of our patient's tumor exceedingly rare, but also, to our knowledge, it is the first reported case of SFT with such a unique vascular supply.

FNA cytology of solitary fibrous tumors and the diagnostic value of STAT6 immunocytochemistry.

Solitary fibrous tumors (SFTs) are rare mesenchymal tumors commonly located in the pleura, soft tissues, or meninges and are characterized by the NGFI-A-binding protein 2 (NAB2)-signal transducer and activator of transcription 6 (STAT6) fusion gene. Recent studies have indicated that nuclear STAT6 immunohistochemistry is a specific marker for SFTs. The authors reviewed fine-needle aspiration (FNA) specimens from extracranial SFTs diagnosed at their institution between 1993 and 2017. Histologic blocks and available formalin-fixed smears of FNA specimens from SFTs were investigated for STAT6 immunoreactivity using a monoclonal antibody. STAT6 immunocytochemistry was also investigated in schwannomas and spindle cell lipomas. Cytopathologic and clinical characteristics were described. Nineteen benign and 9 malignant SFTs were identified. Both benign and malignant SFTs had a female predominance (female-to-male ratio, 2.8:1 and 1.25, respectively). Localization varied, and approximately one-half of the extrapleural tumors were located in the extremities and frequently were intramuscular. Benign and malignant primary tumors had limited differences in cytologic presentation, the most notable feature being nuclear pleomorphism. Cytomorphologic features included low-to-moderate cellularity of mixed oval, elongated, round, and stellate cells with pink collagenous stroma and hypercellular clusters with infrequent atypia. In metastatic SFTs, the cytopathology was suggestive of sarcoma. Immunohistochemistry revealed nuclear STAT6 immunoreactivity in SFTs (n = 5) with cytoplasmic reactivity in cytologic mimickers. Benign and malignant SFTs have common cytopathologic features, and the ability to distinguish between them is limited. Nuclear STAT6 immunoreactivity is a valuable cytologic marker for SFTs. Cancer Cytopathol 2018;126:36-43. © 2017 American Cancer Society.

P2.04-039 Long-Term Risk of Recurrence in Benign Pleural Solitary Fibrous Tumors: A Single Institution Review: Topic: Esophageal Cancer and Other Malignancies

Solitary fibrous tumor (SFT) is a rare tumor of submesothelial origin that can occur in the abdomen, extremities, trunk, head, neck and pleura. Pleural SFTs are defined as benign or malignant based on the number of mitoses and the presence of pleomorphism, hemorrhage, or necrosis. There is limited data in the literature regarding the recurrence risk of benign pleural SFT and the need for long-term follow up in these patients. A single institution retrospective chart review was performed on all surgically resected primary pleural SFTs between 1992 and 2015. Preoperative clinical information, pathologic tumor characteristics, and long-term recurrence and survival data were collected. There were 29 primary pleural SFTs resected between 1992 and 2015. Patients had a mean age of 60 years and there were 16 men (55%) and 13 women (45%). Fourteen (48%) presented with symptoms, including two patients with paraneoplastic syndromes, and the other 15 tumors (52%) were found incidentally on imaging. There were six giant SFTs defined as size greater than 15 cm, with two of six giant SFTs undergoing preoperative embolization to aid surgical resection. Otherwise, there were no neoadjuvant or adjuvant treatments in any patient. There was no perioperative 30-day mortality (0%). Mean follow up time was 77 months, during which 4 (14%) patients recurred and 21 of 29 patients (72%) were alive at last follow up. Three of the 8 deaths occurred in patients with recurrent disease. Among the 19 benign pleural SFTs, 2 (11%) recurred at 5 and 9 years postoperatively and 2 of the 6 malignant SFTs (33%) recurred at 4 and 15 years postoperatively. Margin status was known in 25 cases, of which 21 (84%) were negative and 4 (16%) were positive. There were no recurrences in patients with known negative margins. This study represents one of the largest contemporary single institution reviews of outcomes of pleural SFT. While benign pleural SFTs were less likely to recur than malignant pleural SFTs, benign pleural SFTs with positive or unknown margin status remain at risk for recurrence up to a decade following resection and require ongoing long-term follow up and surveillance imaging.

Solitary Fibrous Tumor of Central Nervous System: Clinical and Prognostic Study of 24 Cases.

Solitary fibrous tumors (SFTs) are rare mesenchymal tumors that occasionally occur in the central nervous system (CNS). It is difficult to fully understand their clinical characteristics, partly due to a limited number of reported cases. We reviewed 24 patients admitted to our institution between 2009 and 2016 with CNS solitary fibrous tumors. We reviewed and analyzed patient profiles, such as demographics, presentations, imaging studies, extent of resection, and adjuvant treatment. Differences between malignant and benign SFTs were assessed using the χ2 test or Student's t-test. Kaplan-Meier analysis was used to estimate the disease-free survival (DFS) rate. The multivariate Cox regression analysis was performed to evaluate the possible predictive value of the DFS rate of the previously mentioned covariates. A total of 13 men and 11 women were enrolled in the study (the average age was 43). The median follow-up time was 58 months. Twenty-one patients underwent gross total resection (GTR), and 3 patients received a subtotal resection (STR). The tumors in 15 patients (62.5%) were atypical or malignant. One patient (4.2%) suffered SFT-related death (multiple organ failure by tumor metastasis), and 3 patients (12.5%) experienced tumor recurrence. We found that a large tumor size (≥10 cm, P < 0.001) and STR (P < 0.001) were negatively associated with the DFS rate. CNS SFTs are rare, slow-growing, less aggressive, and recrudescent tumors. Complete resection is the most effective therapy. Large tumor size and STRs might shorten DFS time.

Integrally calcified solitary fibrous tumor in the retroperitoneum: a case report and review of the literature.

Solitary fibrous tumor (SFT) is a rare stromal neoplasm and usually occurs in the thoracic cavity. We here report a case of retroperitoneal SFT with prominent calcification. A 64-year-old man presented with an incidentally detected retroperitoneal mass in the right upper abdomen. Imaging tests indicated an integrally calcified mass. The lesion was observed for 2 years and laparoscopically resected according to the patient’s wish. Microscopically, the mass was mostly occupied by calcification and proliferous spindle cells were scattered with positive CD34 expression. We diagnosed morphologically benign SFT and the patient remained disease-free 1 year after the excision. There has been no report of such integrally calcified SFT. Retroperitoneal SFT is difficult to make a preoperative diagnosis, and careful follow-up after the excision is recommended because morphological malignancy does not always correspond to clinical malignancy.