Case Of Solitary Fibrous Tumor Research Articles

Immunotherapy for Solitary Fibrous Tumor (Hemangiopericytoma): A Unique Treatment Approach for a Rare Central Nervous System Tumor.

Solitary fibrous tumors (SFTs) of the central nervous system represent a unique entity with limited data on best treatment practices. Here, we present a case of multiply recurrent central nervous system SFT treated with radiation and immunotherapy. Immunotherapy was chosen based on mutations of genes encoding DNA repair enzymes detected through next-generation sequencing of the tumor, DNA polymerase epsilon catalytic subunit (POLE) and mutL homolog 1. The use of radiation and immunotherapy led to slight shrinkage and no recurrence of the tumor for over 2 years. The presence of somatic DNA repair enzyme gene mutations in SFT may suggest a benefit from a combination of radiotherapy and immunotherapy. This may serve as a biomarker for guiding management in patients with this rare tumor.

Imaging characteristics and diagnosis of primary middle mediastinal tumors

Objectives: To investigate the proportion of different histological types and CT enhanced imaging features of primary middle mediastinal lesions in order to improve the understanding of these tumors and the accuracy of preoperative diagnosis. Methods: Retrospective analysis was conducted on 84 patients with primary middle mediastinal lesions and clear histological classifications diagnosed and treated at the Cancer Hospital, Chinese Academy of Medical Sciences from January 2012 to December 2022. Clinical, imaging, and pathological data were collected and classified according to tumor histological classifications. CT imaging manifestations such as tumor location, size, morphology, edge, boundary, internal components, enhancement characteristics, and surrounding tissue invasion were evaluated and recorded. Results: The histological types of the primary middle mediastinal lesions from the 84 patients included mesenchymal tumors, anterior intestinal cysts, giant lymph node hyperplasia, substernal goiter, neuroendocrine carcinoma, lymphohematopoietic system tumors, and mesothelioma, accounting for 28.6%, 27.4%, 14.3%, 3.6%, 11.9%, 9.5%, and 4.8%, respectively. Mesenchymal tumors included peripheral nerve sheath tumors, vascular tumors, adipogenic tumors, solitary fibrous tumors, and synovial sarcoma, accounting for 54.2%, 20.8%, 12.5%, 8.3%, and 4.2%, respectively. The above tumors had diverse imaging manifestations and specific imaging features. Mature fat were found in 3 cases of liposarcoma; Calcification was observed in 2 cases of thyroid nodules and 7 cases of giant lymph node hyperplasia; Enhanced scanning showed significant enhancement in 2 cases of solitary fibrous tumors, 3 cases of thyroid nodules, and 11 cases of giant lymph node hyperplasia; Mediastinal large lymph nodes was observed in 6 cases of lymphoma and 3 cases of mesothelioma; High invasiveness was observed in 4 cases of mesothelioma and 9 cases of neuroendocrine carcinoma. Conclusion: Mediastinal tumors have low incidence rate and rich histological types, and their imaging manifestations are diverse. Preoperative differential diagnosis can be made according to their specific imaging characteristics.

Solitary fibrous tumor of the parapharyngeal space: report of 2 cases and a literature review.

The solitary fibrous tumor (SFT) is usually described as a lesion arising from the pleura. Rarely, it has been described in the parapharyngeal space (PS). This study aims to report two cases of SFT in the PS and to perform a literature review on this topic. Two patients undergoing surgical resection of a SFT in the PS, were reported. A literature review on SFT of the PS, was also performed. Two patients were analyzed. Both patients underwent surgical resection, followed by adjuvant radiotherapy, for SFT arising from the PS. The postoperative course was uneventful and both patients recovered well after the procedure. No recurrences were diagnosed during the followup. SFT of the PS is an infrequent entity. Surgical resection is the most used treatment, and adjuvant radiation should be considered in patients with recurrence risk factors or distant metastases.

Solitary Fibrous Tumor of Nasal Cavity: A Case Report.

Solitary fibrous tumors (SFTs) belonging to a distinct group of mesenchymal tumors, was originally described by Klemper and Rabin in the pleura in year 1931. However, it can also be extra-pleural in origin. With tongue being the most common site involved in this region, epiglottis, larynx, thyroid, external auditory canal, lacrimal sac, hypoglossal nerve, parotid gland, sublingual gland, Para pharyngeal space, nasopharynx, scalp, gingiva, orbit and infratemporal fossa as well as paranasal sinuses and nasal cavities can also get involved. But SFTs involving nasal cavities and nasopharynx are quite uncommon, accounting for < 0.1% of all Sino-nasal neoplasms. Until now there have only been 40 cases of nasal SFT reported in literature. We report the case of an extraserosa solitary fibrous tumor arising from the nasal cavity with extension to the sphenoid sinus, a much rarer presentation of its type. Our case report is one of its type, emphasizing the need conducting further studies on the nature and management of the disease.

Ultrastructural differences between synovial sarcoma and solitary fibrous tumor: comparative study in adult patients from the National Cancer Institute of Mexico

ABSTRACT Synovial sarcoma (SS) and solitary fibrous tumor (SFT) are entities with considerable morphological and immunohistochemical similarities that sometimes show a non-confirmatory profile (TLE1 negative, CD34 and focal or negative STAT6 and lack of specific fusion IHC markers), in which the utility ultrastructure is unknown. A cross-sectional, retrospective, analytical, nonexperimental study was carried out by the Department of Pathology of the National Cancer Institute of Mexico (INCan) e from January 1, 2009 to December 31, 2018. With 17 SFT cases with diffuse or focal CD34 and STAT6 positivity and 18 cases of SS with positive FISH molecular test t(X:18) breakapart were studied by electron microscopy of fresh glutaraldehyde fixed or paraffin-embedded tissue. The ultrastructural findings with a significant difference present in the SS were tandem tight junctions, desmosomes and abundance of dilated rough endoplasmic reticulum (RER) cisternae (p < 0.001, 0.003, and 0.001, respectively); while in the (SFT) the presence of abundant glycogen, basal lamina, long and slender cytoplasmic processes, pinocytic vesicles, hemidesmosomes, and/or dense plaques, collagen skein, and microvilli-like buds (p = 0.028, 0.005, and <0.001 for the last five). We then infer that the five distinctive markers of the SFT are the collagen skeins intermingled with cellular processes in a shape of “squid can,” and the pinocytic vesicles as they were not observed in any case of SS. Conversely, tandem junctions were not found in any SFT case. Although the presence of multivesicular buds in the SFT was not significant, it had not been previously described.

P-02 A case of solitary fibrous tumor originating from the adrenal gland presenting with hypoglycemia

Abstract Introduction Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm usually located in the pleura and associated with NAB2-STAT6 gene fusion. According to the World Health Organization (WHO) classification, although most SFTs are considered well benign, some SFTs have cytological atypia, hypercellularity, tumor necrosis, Ki-67 greater than 5%, high mitotic rate (&amp;gt;4 per high-power field (HPF)) and/or the presence of infiltrative surgical margins are considered malignant. SFT with severe hypoglycemia is called Doege-Potter syndrome which occurs with ectopic secretion of a prohormone of insulin-like growth factor 2 (IGF-2) from tumor tissue. We present a case who applied with severe hypoglycemia and was diagnosed with a solitary fibrous tumor thought to originate from the adrenal gland located in the right retroperitoneal region. Clinical Case A 61-year-old female patient was admitted to the hospital after hypoglycemia was detected in her application due to clouding of consciousness. While the patient's glucose level was 23 mg/dL, insulin:0.4 µIU/mL, C-peptide:&amp;lt;0.01 ng/mL, serum cortisole: 24,20 (µg/mL), growth hormone (GH): 13,20 ng/ mL and insulin-like growth factor I (IGF-1) 38 ng/mL were measured. Insulinoma was excluded and because of IGF-2 level could not be measured in our hospital, low serum insulin and IGF-1 levels suggested high serum IGF-2 levels. HbA1c, adrenal gland, and pituitary function tests were normal (Table 1). A mass lesion of approximately 145×133 mm in size, with heterogeneous contrast, containing cystic areas, was seen, which was thought to originate from the right adrenal gland in the upper abdomen tomography taken due to the presence of a palpable abdominal mass on physical examination (Figure 1). Urine catecholamines were found to be normal, and the plasma aldosterone concentration (PAC)/plasma renin activity (PRA) ratio was 2.56. The patient was operated under intravenous infusion of 10% dextrose due to persistent hypoglycemia. The immunohistochemical evaluation showed CD34, SOX-1 and STAT6 positivity and negativity for S-100, HMB45, straight muscle actin, desmin, caldesmon and melan A, thus confirming the diagnosis of a solitary fibrous tumor. After the operation, the patient's hypoglycemia disappeared. Since there are cases in the literature in which Doege-Potter syndrome was diagnosed without measuring IGF-2, we think that our patient had IGF-2-related hypoglycemia. Conclusion The development of hypoglycemia in Doege-Potter syndrome has been associated with the secretion of large amounts of IGF-2 by tumor tissue, resulting in decreased IGF-1 and Insulin-like growth factor-binding protein 3 (IGFBP-3) concentrations. In these patients, the tumor originates from mesenchymal tumors of low malignant potential. In our case, the Ki-67 proliferation index was around 2%, it was considered benign, and the patient's symptoms completely regressed after resection.Figure 1.CT images of the patientA mass in the right retroperitoneal area, associated with the adrenal gland and containing areas of necrosis, is seen on non-contrast (a) and contrast-enhanced (b) CT scans. Table 1.Laboratory workup

Prognostic analysis of extrameningeal solitary fibrous tumor using the modified Demicco model: a clinicopathologic study of 111 Chinese cases.

Solitary fibrous tumor (SFT) represents a fibroblastic neoplasm exhibiting NAB2::STAT6 gene rearrangement, displaying diverse clinical manifestations, spanning from benign to malignant. To predict prognosis, the modified (four-variable) Demicco (mDemicco) model was introduced. This investigation aims to authenticate the mDemicco risk model's precision in Asian patients while investigating the clinicopathological and molecular factors linked to the prognosis of extrameningeal SFTs. Clinicopathological data from 111 extrameningeal SFT cases in East China, covering the period from 2010 to 2020, were thoroughly analyzed. The tumors were classified using the mDemicco model. Immunohistochemical evaluation of P16 and P53, molecular detection of TP53 and TERT promoter mutation, and fluorescence in situ hybridization for CDKN2A gene alterations were performed. Statistical methods were utilized to assess the associations between clinicopathological or molecular factors and prognosis. Histologically, only one parameter, the mitotic count, exhibited a statistical correlation with progression-free survival (PFS) and overall survival (OS). During the Kaplan-Meier analysis, the variation in PFS among the different risk groups exhibited a notable trend towards statistical significance. Nevertheless, 3 out of 74 patients classified as low-risk SFTs and 7 out of 21 patients classified as intermediate-risk exhibited disease progression. Among the 5 patients with TP53 mutations and/or mutant-type P53 immunophenotype, 3 experienced disease progression, including 2 intermediate-risk patients. Additionally, among the 4 patients with TERT promoter mutations who were followed up, 3 showed progression, including 2 intermediate-risk patients. Moreover, it was observed that hemizygous loss of CDKN2A was detected in more than 30% of one case, yet the patient exhibited a favorable survival outcome. The mDemicco risk model exhibits certain limitations when dealing with smaller tumor sizes, younger age groups, and occurrences of malignant and dedifferentiated SFTs. Furthermore, molecular factors, such as TP53 or TERT promoter mutations, may identify intermediate-risk SFTs with poorer prognoses.

Case Report of Rare Solitary Fibrous Tumour of Nape of Neck with Review of Literature.

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an indolent course but variable metastatic potential. Less than 50 cases of neck SFTs have been documented since 1991. We present a case report of rare presentations of SFT of nape of neck typifying the hypercellular variant of SFT (hemangiopericytoma) with challenges in treatment. Patient underwent excision and was subjected to adjuvant radiation. We concluded that SFT though a rare diagnosis should be considered while dealing with soft tissue tumors and multi-disciplinary pre-operative planning is must to avoid complications and recurrence. Surgical excision remains treatment of choice, but long follow-up is must.

Imaging diagnosis analysis and literature review of intrapulmonary solitary fibrous tumor.

Solitary fibrous tumor (SFT) of the chest mainly arises from the pleura, but intrapulmonary SFT is rare. This study aimed to review and discuss the chest multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) findings of intrapulmonary SFT and summarize existing literature on the disease in order to improve clinicians' understanding and diagnosis of this disease. The imaging findings and clinical data of 4 surgically and pathologically confirmed intrapulmonary SFT cases were retrospectively analyzed in terms of location, morphology, size, density, border, enhancement level of the lesion, and its relationship with surrounding tissue. These findings were combined with a review of 61 cases reported in the literature to characterize the features of intrapulmonary SFT. A total of 65 patients with intrapulmonary SFT were reviewed, consisting of 30 females and 35 males. Of these cases, 21 had a lesion in the left lower lobe, more than in any other part of the lungs. The lesions were clear, had a quasicircular boundary, and were distinctly separated from surrounding tissue. Under plain scan, the 4 cases investigated in this study showed lesions of even density, and enhanced scanning revealed geographic enhancement in 2 cases. Of the 65 cases examined, 56 cases were benign, and the remaining 9 cases were borderline or malignant. The imaging findings of intrapulmonary SFT demonstrated certain features, such as lesions with a clear boundary and even density. Imaging examination is important for the diagnosis and differential diagnosis of this disease.

A Case of Solitary Fibrous Tumor of the Chin

Solitary fibrous tumor (SFT), which was initially believed to be a subtype of mesothelioma, has been reported to occur outside the pleura. In the head and neck region, it primarily manifests in the oral or nasal cavity, with rare occurrences in the facial region. A 40-year-old woman visited our hospital with a mass on her chin. Prior to surgery, involuntary movement was observed in the ipsilateral corner of the mouth upon palpation of the mass. Special care was taken during the surgical procedure to avoid damaging the facial nerve. The mass was excised, and histological examination and immunohistochemical analysis confirmed the diagnosis of an SFT. Here, we present the first reported case of an SFT diagnosed in a jaw mass in Korea. The objective of this study was to highlight the importance of the diagnostic accuracy of SFTs in lower jaw masses.

A Rare Case of Malignant Solitary Fibrous Tumor on the Scalp

Solitary fibrous tumor (SFT) is an uncommon tumor that typically originates in the pleural cavity but may also be found in extra-pleura sites like the head and neck, spine, lungs, mediastinum, peritoneum, and pelvis. There are few reports of SFT of the scalp, and malignant SFT of the scalp appears to be so rare that only two cases of it were reported previously. A 47-year-old woman was admitted to our institution with a large, rapidly growing mass on the left parietal scalp. An analysis of her scalp condition and imaging findings of the mass revealed two different appearances between the superior and inferior halves; the scalp of the inferior half looked normal, but that of the superior half did not. Also, computed tomography findings of the mass confirmed different patterns between the superior and inferior halves. The mass with the abnormal superior half scalp was removed totally. The pathological diagnosis was malignant SFT, but the inferior mass was revealed to have a benign nature. The patient underwent prophylactic radiotherapy and experienced no local recurrence or distant metastasis at the final follow-up at 12 months. We present a third case of malignant SFT originating on the scalp and describe our clinical and surgical experience managing malignant SFT of the scalp.

Solitary fibrous tumor: Two cases report with a focus on the differential diagnosis

Solitary fibrous tumor (SFT) is a neoplasm of fibroblastic/myofibroblastic origin with intermediate biological behavior. We report here two cases of SFT affecting an unusual anatomical site in 58-year-old and 40-year-old female patients and discuss the differential diagnosis of this lesion. In case 01, the lesion showed the clinical appearance of an asymptomatic “blister” with normal color, rubbery consistency, measuring 0.3 cm, and affected the lower lip; while in case 02, a symptomatic red nodular lesion with a soft consistency and measuring 0.5 cm affected the floor of the mouth. Excisional biopsies were performed. Microscopically, two well-delimited benign neoplasms were observed, exhibiting the proliferation of ovoid to spindle-shaped mesenchymal cells, vascular spaces with staghorn arrangement, and the absence of mitosis figures. Immunohistochemistry was performed in case 01 to assist in the diagnosis. Weak and diffuse immunostaining was observed for α-SMA and intense and diffuse immunopositivity for Bcl-2 and CD34. Based on histopathological and immunohistochemical features, a diagnosis of SFT was rendered in both cases. The low occurrence and nonspecific clinical features of oral SFT may make its clinical diagnosis difficult. Also, morphological and immunohistochemical are essential for differential diagnosis with other mesenchymal neoplasms.

Solitary fibrous tumor in the temporalis muscle: a case report and literature review.

Solitary fibrous tumor (SFT) is an infrequently occurring neoplasm most commonly observed in the pleura, but it can develop in the head and neck region in occasional cases. However, no reports have described SFT in the temporalis muscle. Herein, we present the first known case of SFT in the temporalis muscle. A 47-year-old man complained of a painless palpable mass on his right temple. Facial enhanced computed tomography identified a 4.0× 2.9× 1.4 cm mass presenting as a vascular tumor in the right temporalis muscle under the zygomatic arch. The mass was excised from the right temporalis muscle under general anesthesia. A histopathologic examination revealed that the mass was an SFT. No complications occurred after surgery, including functional disability or sensory loss. The patient was followed up for 3 months without complications. Although SFT in extrapulmonary regions is rare, it should be considered in the differential diagnosis of masses that occur in the temporal area.

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

BackgroundIntrathoracic 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 presentationA 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.ConclusionMediastinal 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.

Successful resection of a hypervascular paravertebral solitary fibrous tumor of pleura preserving the artery of Adamkiewicz, which was detected on preoperative angiography

BackgroundSolitary fibrous tumor of the pleura is rarely observed, accounting for 1% of all mediastinum tumors. There have been only a few reports of preoperative embolization for hypervascular tumors around the artery of Adamkiewicz (AKA). We report a rare case of solitary fibrous tumor for which transcatheter embolization was successfully performed before surgical resection.Case presentationA 66-year-old woman with sudden-onset back pain was referred to our hospital for the evaluation of a left intrathoracic abnormal shadow on chest X-ray. Preoperative computed tomography (CT) showed a large, posterior mediastinal, paravertebral, and well-demarcated mass with high contrast enhancement and significant vascularization fed by the intercostal artery (ICA), measuring 8.1 × 7.6 × 6.4 cm. Therefore, solitary fibrous tumor, unicentric Castleman disease, or paraganglioma was included in the differential diagnosis. The patient underwent preoperative transcatheter arterial embolization followed by surgical extirpation. Thanks to the appropriate assessment of the anatomy, we could resect the tumor safely. The pathological diagnosis was solitary fibrous tumor of pleura.ConclusionsWe recommend preoperative transcatheter arterial embolization (TAE) for hypervascular tumors close to the AKA that may require surgical removal; to reduce intraoperative hemorrhage, the AKA should be accurately detected during surgery.

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

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.

Solitary fibrous tumor of the tympanic membrane a case report and systematic review

PurposeOtological solitary fibrous tumors (SFT) are exceedingly rare. There has been no report of SFT localized to the tympanic membrane. To report on a rare case of solitary fibrous tumor of the tympanic membrane and provide systematic review of the literature pertaining the demographics and pathophysiology of otological SFTs. Materials and methodsThis review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. A search of PubMed, Google Scholar, and Cochrane Library databases was conducted to identify English-language articles on solitary fibrous tumor of the ear, with emphasis on the tympanic membrane, published through 2022. A combination of Boolean operators and the following keywords were included in the search strategy: “solitary fibrous tumor”, “tympanic membrane”, and “ear”. ResultsWe found 12 previous reports of solitary fibrous tumors of the ears, none of which were in the tympanic membrane. All cases underwent surgical resection, with or without perioperative embolization, or radiation. There was no evidence of distant diseases in any cases. ConclusionsIn the context of a tympanic membrane mass with associated pain and hearing loss, our findings suggest that solitary fibrous tumor should be included in the differential diagnosis.

A diagnostic challenge; pelvic solitary fibrous tumor (SFT) mimicking Peri‐Anal gastrointestinal stromal tumor (GIST): A case report

Key Clinical MessageThe study reports a rare case of pelvic solitary fibrous tumor (SFT) that was initially considered as a peri‐anal gastrointestinal stromal tumor due to similar radiologic/pathologic features. SFT diagnosis can be challenging due to its rarity and wide range of diagnoses that must be ruled out precisely.AbstractSolitary fibrous tumors (SFTs) are rare tumors that can occur in any part of the body. Although usually benign, malignant SFTs have been reported, especially outside the lungs. Radiology can help with diagnosis, but immunohistochemistry is necessary to distinguish SFTs from other possible diagnoses such as gastrointestinal stromal tumors (GISTs). This study presents a rare case of pelvic SFT initially considered to be a peri‐anal GIST, highlighting the importance of accurate diagnosis given the rarity of SFTs and the need to rule out other potential diagnoses.

PERSISTENT SOLITARY FIBROUS TUMOR APPEARING AS AN AGGRESSIVE MANDIBULAR RADIOLUCENCY

We report an unusual case of solitary fibrous tumor (SFT) with persistent behavior. A 41-year-old female was referred for evaluation due to tender swelling on the right chin of unknown duration. Intraoral examination revealed a firm well-circumscribed mass in the right lower buccal vestibule and imaging exams showed slight buccal cortical resorption. An incisional biopsy was performed, and microscopic analysis revealed cellular proliferation of bland spindle cells, admixed with dense collagen, prominent staghorn blood vessels, and positivity for CD34, CD99, Bcl-2, and positive nuclear staining for STAT6, rendering a diagnosis of SFT. Five years after complete surgical excision of the tumor, the patient presented a 3 cm, ill-defined expansive radiolucency in the right mandibular body, which was microscopically diagnosed as persistent SFT. No signs of malignancy were observed. SFT closely related to the mandible may persist after long-term follow-up, appearing as aggressive and extensive radiolucency. We report an unusual case of solitary fibrous tumor (SFT) with persistent behavior. A 41-year-old female was referred for evaluation due to tender swelling on the right chin of unknown duration. Intraoral examination revealed a firm well-circumscribed mass in the right lower buccal vestibule and imaging exams showed slight buccal cortical resorption. An incisional biopsy was performed, and microscopic analysis revealed cellular proliferation of bland spindle cells, admixed with dense collagen, prominent staghorn blood vessels, and positivity for CD34, CD99, Bcl-2, and positive nuclear staining for STAT6, rendering a diagnosis of SFT. Five years after complete surgical excision of the tumor, the patient presented a 3 cm, ill-defined expansive radiolucency in the right mandibular body, which was microscopically diagnosed as persistent SFT. No signs of malignancy were observed. SFT closely related to the mandible may persist after long-term follow-up, appearing as aggressive and extensive radiolucency.

Clinical and pathological analysis of 35 cases of ocular adnexal solitary fibrous tumor

Objective: To analyze the clinical and pathological characteristics and prognosis of 35 cases of solitary fibrous tumor of ocular adnexal (SFT). Methods: This was a retrospective case series study. The clinical data of 35 cases of ocular adnexal SFT was collected in Tianjin Eye Hospital from January 2000 to December 2020. The clinical manifestations, imaging examination results, pathological characteristics, treatment of patients were analyzed, and patients were followed up. All cases were classified according to the 2013 classification of World Health Organization of tumors of soft tissue and bone. Results: There were 21 males (60.0%) and 14 females (40.0%). The age range was 17 to 83 years, and the median age was 44 (35, 54)years. All patients were unilateral, with 23 (65.7%) in the right eye and 12 (34.3%) in the left eye. The course of disease ranged from 2 months to 11 years, with an a median duration of 12(6,36)months. Clinical manifestations included exophthalmos, limited eye movements, diplopia, and tearing. All patients underwent surgical treatment of complete resection of the tumor. Ocular adnexal SFT mostly occurred in the upper orbit (19 cases, 73.1%). On imaging examination, the tumor showed well-circumscribed space occupying lesion that heterogeneously enhanced with contrast, and abundant blood flow signals in the tumors. MRI showed isointensity or low signal on T1WI, and significantly enhanced on T2WI, presenting intermediate-to-high heterogeneous signals. The tumor diameter was 2.1 (1.5, 2.6) cm. There were 23 cases (65.7%) of classic subtype, 2 cases (5.7%) of giant cell subtype, 8 cases (22.9%) of myxoid subtype, and 2 cases (5.7%) of malignancy. Immunohistochemical staining showed that Vimentin, CD34 and STAT6 were positively expressed in all patients. Twenty-one cases (60.0%) showed positive expression of BCL-2, and Ki-67 positive index ranged from 1.0% to 10.0%. Tumors in this group were all low-risk according to the Demicco risk stratification. Follow-up was available for 25 patients with a duration of 2 years to 14 years and 7 months, and the median follow-up time was 88 (61, 124) months. Two patients relapsed, and no distant metastasis or death was observed. Conclusions: Ocular adnexal SFT mainly presents as a painless, slow-growing mass. And most of them are typical SFT. The imaging manifestations are varied Ocular adnexal SFT generally follows a benign course, with a good prognosis after complete excision. Recurrence could occur many years after surgery which requiring careful and long-term follow-up.