Solitary fibrous tumors and so-called hemangiopericytoma

Primary Omentum Malignant Hemangiopericytoma Present with Acute Abdomen

The greater omentum primary malignant tumors are rare, with less than 50 cases reported. Malignant hemangiopericytomas constitute only four of these cases. The common clinical manifestations of a malignant omental tumor are abdominal mass and pain. We report on a woman 38 years old who came to the hospital's emergency department with a finding consisting of intestinal obstruction (abdominal pain, constipation, abdominal distention, and vomiting), and during a clinical examination a mass was discovered in the lower half of her abdomen. She had been experiencing these symptoms for three days before her arrival. During a clinical examination, a large size, hard mobile mass was discovered in the lower half of her abdomen. The patient underwent an abdominal CT scan which indicated the presence of a sizable, soft tissue mass located within the abdominal and pelvic region, exerting pressure on the small bowel loops, with mild free ascites. Due to the patient's acute abdomen, an exploration laparotomy was performed, revealing a large mass in the omentum measuring 20×20×10 cm and weighing 3 kg. The mass, along with the omentum, was completely removed, and histopathology confirmed a malignant hemangiopericytoma.

STAT6-targeting antisense oligonucleotides against solitary fibrous tumor

Solitary fibrous tumor (SFT) is a rare, non-hereditary soft tissue sarcoma thought to originate from fibroblastic mesenchymal stem cells. The etiology of SFT is thought to be due to an environmental intrachromosomal gene fusion between NGFI-A-binding protein 2 (NAB2) and signal transducer and activator protein 6 (STAT6) genes on chromosome 12, wherein the activation domain of STAT6 is fused with the DNA-binding domain of NAB2 resulting in the oncogenesis of SFT. All NAB2-STAT6 fusion variations discovered in SFTs contain the C-terminal of STAT6 transcript, and thus can serve as target site for antisense oligonucleotides (ASOs)-based therapies. Indeed, our in vitro studies show the STAT6 3' untranslated region (UTR)-targeting ASO (ASO 993523) was able to reduce expression of NAB2-STAT6 fusion transcripts in multiple SFT cell models with high efficiency (half-maximal inhibitory concentration: 116-300 nM). Encouragingly, in vivo treatment of SFT patient-derived xenograft mouse models with ASO 993523 resulted in acceptable tolerability profiles, reduced expression of NAB2-STAT6 fusion transcripts in xenograft tissues (21.9%), and, importantly, reduced tumor growth (32.4% decrease in tumor volume compared with the untreated control). Taken together, our study established ASO 993523 as a potential agent for the treatment of SFTs.

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.

Rarest of the Rare - Malignant Solitary Fibrous Tumour of the Breast: Case Report and Literature Review

Malignant solitary fibrous tumor of the breast is one of the rarest types of breast malignancy. To the best of our knowledge, only six cases have been reported so far. Here we have presented such a case from India, where a 52-year-old lady presented with a 10 cm x 8 cm breast lump. Diagnosis was achieved with the help of FDG PET, histopathology and immunohistochemistry, which showed nuclear positivity for STAT6. Fluorescent in situ hybridization (FISH) molecular study for SS18-SSX was used to rule out the differential diagnosis of synovial sarcoma. Guidelines for the management of this type of breast malignancy still do not exist. We have done a review of the literature in order to discuss which might be the best management in such cases. Evidence on this very rarest type of breast malignancy is still evolving. The interest in the case described here relies on its rarity, difficulties in achieving diagnosis and formulation of the proper management.

Ga68-FAPI Imaging and Lu177-FAPI Therapy in a Case of Metastatic Solitary Fibrous Tumor

Solitary fibrous tumor (SFT) of the central nervous system (previously called hemangiopericytoma) is a rare mesenchymal tumor. Malignant SFT has a tendency to recur after surgery and can metastasize to distant organs. Treatment options for metastatic disease are limited. This case demonstrated high expression of FAP (fibroblast activating protein) in all metastatic sites with Ga-FAPI positron emission tomography-computed tomography imaging. Subsequently, the patient was treated with Lu177-FAPI-targeted radionuclide therapy. There was significant clinical response. There was mild partial morphological response seen on follow-up imaging.

Solitary Fibrous Tumor of Parapharyngeal Space: A Rare Case Report

Solitary fibrous tumors are rare vascular tumours, earlier referred to as hemangiopericytoma. Their occurrence in parapharyngeal space is very rare. Hence, they should also be considered in the differential diagnosis of parapharyngeal soft tissue tumours. This case is being reported to bring out an extremely rare vascular tumour at rare site and represents a surgical challenge because of difficult access in parapharyngeal space with difficult planes between tumour and rest of parapharyngeal space, approach to it is also difficult.

Bilobed flap reconstruction after en-bloc removal of solitary fibrous tumor of the lacrimal sac

Purpose

To report a rare case of a solitary fibrous tumor (SFT) of the lacrimal sac and discuss considerations for management of similar cases.

Observations

We present the case of a 41-year-old woman who presented with a primary lacrimal sac SFT for which she underwent en-bloc surgical resection. We discuss management options for SFTs and our surgical approach for this case: bilobed flap reconstruction of the medial canthus and inferior orbit.

Conclusions

We present an uncommon presentation of a rare tumor and a successful one-stage reconstruction with a bilobed flap.

Combined extradural and intradural approach to a trigeminal nerve hemangiopericytoma with cranial nerve monitoring: a technical note of a rare case

Hemangiopericytoma (HPC) of the trigeminal nerve is extremely rare. We present a case of a large cystic HPC of the mandibular division of the trigeminal nerve, only the third case described in the literature, with both intradural and extradural components. We describe the surgical approach, assisted by neurophysiological techniques of mapping and monitoring including blink reflex and triggered electromyography. Additionally, we report a method of monitoring of the sensory branches of the trigeminal nerve, poorly described in the literature, through peripheral and direct nerve stimulation and recording of transcranial somatosensory evoked potentials.

Case report: 125I seed implantation for rare malignant solitary fibrous tumor in the pelvic cavity: a case report

Solitary fibrous tumor (SFT) is a rare spindle cell tumor, benign or low-grade malignant, with an extremely low possibility of occurrence of malignant solitary fibrous tumor (MSFT). Surgery is an effective way for treating SFT, but it is often difficult to resect completely due to a large size, with a high recurrence rate and mortality rate after operation. Additionally, SFT is relatively resistant to chemotherapy, and there is a lack of effective systemic drug treatment. These lead to certain difficulties in the treatment of SFT. We report a case of a rare MSFT in the pelvic cavity. With a history of recurrence after two surgeries, this patient underwent surgical removal combined with ¹²⁵I seed implantation at our hospital in the context that the tumor could not be completely removed because it was large and adhered to surrounding tissues; after up to 43 months of progression-free survival (PFS), the patient underwent ¹²⁵I seed implantation alone, and achieved a complete remission, with a PFS up to 35 months. ¹²⁵I seed implantation can be a safe and effective treatment option for unresectable MSFT as well as a potential solution to repeated local recurrence.

Malignant renal hemangiopericytoma: a case report

Malignant hemangiopericytoma (HPC) is an uncommon disease first described by Stout and Murray in 1942. Patients with suspected renal HPC on admission sometimes complain of low back pain, hematuria, or hypertension. A combination of histochemical and anatomo-pathologic examinations is necessary to confirm the diagnosis of renal HPC. We report the case of a 41-year-old female patient who had persistent painful nodular lesion at the right lower back and gross hematuria. Based on analyses of clinical symptoms and signs plus radiological a laboratory examination, she was diagnosed with renal cell carcinoma of the right kidney. She subsequently underwent open right radical nephrectomy via transperitoneal approach. The patient was discharged from hospital in good condition on Day 5 of care after surgical intervention. Malignant HPC of the kidney is an uncommon disease that can be diagnosed based on multislice computerized tomography angiography plus histopathological examination using the periodic acid shift method. Management of malignant renal HPC requires radical nephrectomy followed by chemotherapy. This case study provides important preliminary data for further studies of patients with renal HPC in Indonesia.

[Treatment of a patient with giant solitary fibrous tumor of the left hip]

The authors report surgical treatment of a 59-year-old female with a giant solitary-fibrous tumor of the left hip. Previous excision of hip hemangioma was performed in 2016. Recurrent tumor with fast growth has occurred since 2018. The neoplasm consisted of 2 tumors connected by vascular structures. CT revealed soft tissue neoplasms in the upper third of the left thigh (anterior, medial and dorsal regions). Large tumors with an isthmus along the inner surface had tuberous contours and internal septa. The last ones and walls accumulated contrast agent. No structural damage to femoral muscles was observed. The patient underwent resection of tumor and vascular ligation (great saphenous vein and its tributaries along the anterior surface, arteries from the deep femoral artery system along the posterior surface of tumor). There were no early postoperative complications. There are no complaints within 6 month after surgery. There is no lower limb dysfunction.

Fascin-1 is associated with recurrence in solitary fibrous tumor/hemangiopericytoma

Fascin-1, an actin-bundling protein, is associated with poor prognosis in patients with various types of human carcinoma. However, research is limited on the role of fascin-1 in sarcoma. Solitary fibrous tumor (SFT) and hemangiopericytoma (HPC) are rare sarcomas derived from the mesenchyme. Although the prognosis of SFT/HPC is generally favorable, fatalities are possible with repeated recurrence and distant metastasis. The current study included a total of 20 Japanese patients, who were diagnosed with SFT/HPC and underwent surgery at Kochi University Hospital from January 2000 to December 2019. The statistical relationship between recurrence and the following variables were examined: Sex, age of onset, tumor origin, tumor size, necrosis, mitosis ≥1/10 high power field (HPF; magnification, x400), Ki-67 >5% and Fascin-1. A significant association was determined between recurrence and necrosis, mitosis ≥1/10 HPF (magnification, x400), Ki-67 >5%, and Fascin-1 ≥‘strongly positive’ (P<0.05). The results demonstrated that Fascin-1 immunostaining may be a highly effective and useful evaluation factor for predicting poor prognosis in patients with SFT/HPC, a fatal sarcoma of humans.

Severe hypoglycemia and finger clubbing in a patient with a BRCA1 mutation in a solitary fibrous tumor: a case report

Solitary fibrous tumors (SFTs) are rare tumors that stem from mesenchymal cells of submesothelial tissues belonging to the pleura. They can occur in many places such as the spinal canal, intracranial, neck, kidney, liver, pelvis, limbs and other places, most commonly in the chest and abdomen. Pleural SFTs are one of the most common types, and are common in middle-aged people. Pleural SFTs can have an insidious expression, such that the illness can progress for years before diagnosis. SFTs can induce paraneoplastic syndromes, such as reactive hypoglycemia [Doege-Potter syndrome (DPS)] or hypertrophic osteoarthropathy [Pierre-Marie-Bamberger syndrome (PMBS)]. In this article, we report a case study of a 51-year-old man with pleural SFTs. Preoperative imaging examinations, including chest X-ray, computed tomography (CT), and magnetic resonance imaging (MRI), showed a huge mass in the right thoracic cavity, compressing surrounding tissues and organs and may invade other tissues. In addition, he suffers from severe hypoglycemia and finger clubbing, and has successfully undergone a complete resection, and now attends regular follow-up appointments. The paraneoplastic syndromes have resolved, and no recurrence has been found. Importantly, we used next-generation sequencing (NGS) to explore the molecular characteristics of the patient’s pathological tissue at the DNA level and mRNA level, and found that breast cancer gene 1 (BRAC1) mutations may be an important pathogenic factor.

Radiologic-Pathologic Correlation of Primary Retroperitoneal Neoplasms

An earlier incorrect version of this article appeared in print. The online version is correct.

Doege-Potter Syndrome: A Presumptive Case of Metastatic Hemangiopericytoma with Persistent Hypoglycemia in a 27-Year-Old Male

Doege-Potter syndrome (DPS) is a rare paraneoplastic condition characterized by hypoinsulinemic hypoglycemia from a solitary fibrous tumor. The underlying mechanism is the secretion of a prohormone form of insulin-like growth factor II (IGF-II) by the tumor, which causes decreased release of glucose into the circulation. We report the case of a 27-year-old Filipino male with presumptive DPS from a recurrent right temporo-zygomatic hemangiopericytoma (HPC). The complexity of DPS requires a multidisciplinary approach. Early screening for metastases from HPC may prevent the undesirable sequelae of the disease process.

Solitary fibrous tumor of thoracic cavity, extra-thoracic sites and central nervous system: Clinicopathologic features and association with local recurrence and metastasis

Published risk stratification models of solitary fibrous tumor (SFT) have been associated with distant metastases outside the central nervous system (CNS), but have not been studied for tumors occurring in the CNS. In a retrospective review, we identified 72 cases of solitary fibrous tumor or hemangiopericytoma (HPC) diagnosed between January 2011 and December 2020 at our institution. The tumors involved the central nervous system (N = 17), thoracic cavity (N = 28), and extrathoracic sites (N = 27). The risk of local recurrence, distant metastasis, or death at 5 years was 57% (95% CI 23%, 76%) in the CNS, 24% (95% CI 2%, 41%) in the thoracic cavity, and 13% (95% CI 0%, 25%) in extrathoracic sites. By contrast, the risk of distant metastasis or death at 5 years was 13% (95% CI 0%, 29%) in CNS primaries, 5% (95% CI 0%, 14%) in thoracic primaries, and 14% (95% CI 0%, 27%) in extrathoracic primaries. Using the published 3- and 4-variable risk stratification models by Demicco et al., we retrospectively assessed our cases for risk of local recurrence, distant metastasis, and death. For tumors outside the CNS, we show that three- and four-variable risk stratification models were associated with recurrence-free survival in addition to the previously known association with distant metastasis (all P < 0.05). In contrast, inside the CNS, we show that neither risk model is a significantly associated with clinical behavior, and that WHO grade is likely the best available prognostic tool, though none of the differences were significant. The lack of significant differences can be likely explained by the younger median age (47 years vs 61 years) and smaller median tumor size (3.5 cm vs 5.6 cm), downgrading the risk stratification scores in CNS compared to non-CNS primaries. In conclusion, existing risk stratification models of SFT are not associated with clinical behavior for tumors arising inside the CNS, but are associated with local recurrence in addition to distant metastasis outside the CNS.

Malignant haemangiopericytomas of omentum presenting as left inguinal hernia: A case report

Background

Hemangiopericytomas (HPC) are vascular tumors and can be found at any place where vessels are present. These were previously known as ‘extrapleural Solitary Fibrous Tumour’. These tumors may reoccur and metastasize after surgical excision. We present herein a HPC of the greater omentum, diagnosed as left inguinal hernia preoperatively.

Case presentation

A 61-year-old male, presented with a huge painless mass in his left inguinoscrotal region secondary to weigh-lifting associated with malaise and vague abdominal pain. A well-defined, non-tender, and firm mass was found at the left lower abdomen extending to the left inguinoscrotal region. Based on the examination, a diagnosis of indirect inguinal hernia was made. Abdominal ultrasound showed a heterogeneous, hyporeflective, and vascularized mass. Contrast-enhanced computed tomography scan identified a localized, extraperitoneal, heterogeneously hypodense, well-defined, and lobulated mass, with marked contrast enhancement. On exploration, an encapsulated large mass originating from the omentum with enormously dilated blood vessels was excised. On histopathology, a neoplastic lesion, composed of spindle-shaped cells and moderate cytoplasm was identified. The blood vessels appeared thin-walled with a staghorn appearance in hemangiopericytic pattern. Omental sections showed fibro adipose tissue with dilated lymphatics and thick-walled blood vessels. Features were consistent with a malignant HPC of 20 × 14 × 10 cm.

Conclusion

We present an unusual presentation of primary omental malignant HPC as an inguinal hernia, treated by complete surgical resection. These tumors are rare therefore, timely diagnosis is important for proper evaluation, diagnosis, and treatment. It also requires long-term follow up for better survival.

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Hemangiopericytoma (HPC), previously known as ‘extrapleural Solitary Fibrous Tumor’, is a vascular tumor.

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A well-defined, non-tender, and firm mass was found at the left lower abdomen extending to the left inguinoscrotal region.

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Based on the examination, a diagnosis of indirect inguinal hernia was made.

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CT scan showed a contrast enhancing, localized, extraperitoneal, heterogeneously hypodense, and lobulated mass.

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On exploration, an encapsulated large mass originating from the omentum with enormously dilated blood vessels was excised.

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On histopathology, features were consistent with a malignant HPC of 20 × 14 × 10 cm.

Intracranial solitary fibrous tumor/hemangiopericytoma - A case series

Background:

Intracranial solitary fibrous tumor/hemangiopericytoma (HPC) is a rare and aggressive tumor. We conducted this retrospective study to investigate the outcome of patients after treatment, the efficacy of postoperative adjuvant radiotherapy, and the factors not conducive to total resection.

Methods:

We conducted a retrospective review of the medical records of patients harboring fresh intracranial solitary fibrous tumor/HPC treated from January 2009 to December 2019 in our hospital. We reviewed their clinical presentations, radiologic appearances, tumor size and location, extent of resection, estimate intraoperative blood loss, treatment modalities and results, and duration of follow-up.

Results:

There were seven consecutive patients (three males and four females). The ages of the patients at the time of diagnosis ranged from 35 to 77 years (mean: 52.86 years). Five patients (71.43%) got tumor bigger than 5 cm in dimension and only 1 patient (14.29%) underwent gross total tumor resection in the first operation without complication. Five patients (71.43%) underwent postoperative adjuvant radiotherapy. Follow-up period ranged from 4.24 to 123.55 months and the median follow-up period was 91.36 months. Three patients had favorable outcome with Glasgow Outcome Scale (GOS) equal to 4; four patients had unfavorable outcome with GOS equal to 2 or 3. No mortality was happened.

Conclusion:

Gross total tumor resection in the initial surgery is very important to achieve a better outcome. Massive intraoperative bleeding and venous sinus or major vessels adjoining are factors not conducive to total resection. Radiotherapy can be administered as adjuvant therapy for cases showing an aggressive phenotype or not treated with gross total resection.

[What's new in the management of meningeal solitary fibrous tumor/hemangiopericytoma?]

Meningeal fibrous solitary tumors/hemangiopericytoma are rare and aggressive mesenchymal neoplasms considered as sarcomas. They represent less than 1% of intracranial tumors and derive from the pericytes of Zimmerman which permit capillary contraction. They tend to occur more often in males in the fifth decade. They are often revealed by intracranial hypertension. Some scannographic and MRI characteristics permit to distinguish meningeal fibrous solitary tumor/hemangiopericytoma from other meningeal tumors. Meningeal hemangiopericytoma and fibrous solitary tumors were considered as different entities until 2016. Following the discovery of an identical genetic event, the locus 12q13 chromosome inversion leading to a NAB2-STAT6 fusion with nuclear immunoreactivity for STAT6 protein, the 2016 WHO classification defines these tumors as a single entity. Meningeal fibrous solitary tumors/hemangiopericytoma have a high recurrence rate. Long-term recurrences may occur. Local relapses are more frequent than extracranial metastasis. A multimodal management is recommended to treat a localized disease. It involves a complete resection followed by adjuvant radiotherapy. When local recurrences occur, surgery or stereotactic radiosurgery permit sometimes a local control. Metastatic disease has a poor prognostic and a weak chimiosensitivity. Targeted therapies, like pazopanib, are a hopeful option.

Fibrous solitary tumor, a rare and ubiquitous neoplasy

Fibrous solitary tumors (FST) are mesenchymal tumors that can appear in different body regions. It is estimated that around 30% are found in the thoracic region, while rarely in meninges, abdomen, pelvis, extremities and bones. A correct diagnosis is important because 15-20% of cases develop a malignant behavior. Treatment of choice is surgical and posterior follow-up is essential. We present two atypical extrapleural FST cases, diagnosed in our center. Both were treated with surgery and in one case arterial embolization to reduce the bleeding risk was previously done.

Central Nervous System Solitary Fibrous Tumor/Hemangiopericytoma Penetrating the Skull Bone: An Unusual Presentation

BACKGROUND

Central nervous system (CNS) solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a soft tissue neoplasm that accounts for <1% of all intracranial tumors. Its growth will be mostly intracranial, usually along the sinuses. We have reported a rare case of direct extracranial extension of CNS SFT/HPC penetrating the frontal bone.

CASE DESCRIPTION

A 64-year-old woman had visited our institution for treatment of a forehead mass. With the impression that it was a subcutaneous mass, we had planned a simple excision with the patient under local anesthesia. However, the intraoperative findings showed extension of the mass into the skull and attachment to the dura mater. Brain magnetic resonance imaging showed a 1.8-cm solid mass with an adjacent skull defect, and examination of the biopsy specimen confirmed the diagnosis as grade II CNS SFT/HPC. Definitive excision was performed by en bloc tumor resection with a 2-cm safety margin. Adjuvant radiotherapy was performed with 60 Gy in 30 fractions. The patient showed no signs of recurrence or metastasis during 2 years of follow-up.

CONCLUSIONS

The present case has shown that CNS SFT/HPC can infiltrate the full thickness of the skull bone and grow extracranially, even if low grade. However, the unusual presentation of the present made early exploration and total resection possible.

Combined Surgical Approach to Intracranial and Extracranial Hemangiopericytoma: Case Report and Literature Review

Hemangiopericytoma (HPC) is a rare vascular tumor that was first described in 1942 and whose classification and treatment continue to develop. The proper classification for HPC is still under discussion, being considered a solitary fibrous tumor (SFT), classified as an aggressive biological form. The World Health Organization (WHO) has considered it to be part of extrapleural solitary fibrous tumors, however, neuropathologists still consider it to be an HPC when it is found in the central nervous system. We present a case of a patient with HPC of complex localization in the infratemporal fossa and middle floor of the skull base, which confirmed the diagnosis of HPC after resection by the craniofacial approach. Hemangiopericytomas are tumors that can present along with distant metastasis in 23% of cases even after resection. Surgery is the therapeutic basis; however, the still-controversial pathological classification of these vascular tumors and their uncertain biological behavior are the main reasons the ideal treatment continues to be investigated.

Nervous System Hemangiopericytoma

The management of patients harboring central nervous system (CNS) hemangiopericytomas (HPCs) is a partially answered challenge. These are rare locally aggressive lesions, with potential for local recurrence, distal neural metastasis (DNM), and extraneural metastasis (ENM). Resection, when feasible, remains the initial treatment option, providing histological diagnosis and immediate relief of tumor-related mass effect. Patients receiving surgery alone or surgery and external beam radiotherapy (EBRT) show improved overall survival (OS) and progression-free survival as compared to those undergoing a biopsy alone (p = 0.01 and p = 0.02, respectively). Yet, in many instances, patient and tumor-related parameters preclude complete resection. EBRT or stereotactic radiosurgery (SRS) shares a significant role in achieving local tumor control, not shown to impact OS in HPC patients. The benefits of SRS/EBRT are clearly limited to improved local tumor volume control and neurologic function, not affecting DNM or ENM development. SRS provides acceptable rates of local tumor volume control coupled with treatment safety and a patient-friendly apparatus and procedure. Single-session SRS is most effective for lesions measuring <2 cm in their largest diameter (10 cm3 volume), with prescription doses of at >15 Gy. Systemic HPC disease is managed with various chemotherapeutic, immunotherapeutic, and anti-angiographic agents, with limited success. We present a short discussion on CNS HPCs, focusing our discussion on available evidence regarding the role of microsurgical resection, EBRT, SRS, chemotherapy, and immunotherapy for upfront, part of adoptive hybrid surgery approach or for recurrent HPCs.

Cystic appearance - a new feature of solid fibrous tumours in the lacrimal gland: a case report with literature review

Background

Solitary fibrous tumours (SFTs) rarely occur in the orbit, especially in the lacrimal area. These tumours are mostly solid. Cystic changes have been documented, but they remain very rare. Only three cases of primary orbital solitary fibrous tumours with cystic changes have been reported in the literature, but no cases have been reported to occur in the lacrimal gland. Solitary fibrous tumours generally follow a benign course and are treated definitively with surgical excision. Data from the literature suggest that the cystic nature of SFT presents a risk of recurrence and could be a harbinger of malignancy.

Case presentation

A 42-year-old woman was admitted to the endocrinology department for right unilateral exophthalmia and epiphora in the last 8 months. An ophthalmological evaluation showed exophthalmia only in the right eye (22 mm) and normal visual acuity, visual field and extraocular movements. Investigations revealed normal thyroid function. Orbital magnetic resonance imaging detected a 4 × 2,2 × 2,7 cm septate pseudocystic mass in the right lacrimal gland. Given her lacrimal gland tumour diagnosis, the patient was submitted for neurosurgical intervention with total ablation of the tumoural mass and complete right dacryoadenectomy. Although the intraoperative extemporaneous examination results were suggestive of a haemangiopericytoma, histological and immunocytochemical examination showed an extrapleural SFT. The postoperative clinical evolution was favourable, with remission of the exophthalmia. Fifteen months after surgery, no signs of recurrence were noticed.

Conclusions

We report the first case of an SFT with cystic changes in the lacrimal gland. Although the presence of cavitary lesions alone does not necessarily indicate aggressive behaviour, cystic changes pose a risk of recurrence and may suggest malignant transformation over time. As a result, our case requires long-term follow-up due to recurrence and malignant potential.

Solitary fibrous tumour of caecum wall: an unlikely cause of low gastrointestinal haemorrhage

Solitary fibrous tumour (SFT), previously denominated as haemangiopericytoma, is a rare, spindle cell neoplasm that was first described in the thoracic pleura. It is now known that this tumour may develop from almost any anatomic location. We report a case of SFT, in a 65-year-old man, which was located in the muscularis propria layer of the caecum with involvement of the serosa and the ileocecal appendix, location never described in the literature, and with an uncommon clinical presentation of hematochezia. A radical right hemicolectomy was performed, and the patient was asymptomatic without evidence of metastasis or relapse after 6 months of follow-up.

Solitary Fibrous Tumor of Pleura Invading into the Left Atrium via Pulmonary Vein

A 67-year-old woman came to the hospital because of difficulty in breathing. After an initial clinical assessment, contrast-enhanced computerized tomography (CT) of the chest revealed a well-circumscribed heterogeneous mass arising from the pleura adjacent to the superior and medial left pulmonary artery. The mass was invading the pulmonary vein and entering the left atrium. Histopathology of the biopsy of the mass was suggestive of solitary fibrous tumor (SFT) of the pleura. The patient underwent pneumonectomy and resection of the left atrial mass with pericardial patch repair of the left atrium.

Solitary Fibrous Tumour: A Single Institution Retrospective Study and Further Validation of a Prognostic Risk Assessment System

AIMS

Solitary fibrous tumour (SFT) is a rare mesenchymal-derived neoplasm that can arise in any anatomical location in the body. SFT rarely metastasises, but aggressive behaviour is seen in a minority of cases, and relapses can occur several years after treatment. It would be a clinical advantage if high-risk patients could be identified before treatment.

MATERIALS AND METHODS

We retrospectively analysed a population-based cohort of SFT to describe treatment, outcome, prognostic factors and to further validate a previously published risk assessment tool (D-score) based on age, tumour size and mitotic index. Seventy-two patients diagnosed with SFT in the Central, North and Southern Denmark regions between 1979 and 2013 were included in the study.

RESULTS

For patients with localised disease at the time of diagnosis (n = 64) the 5 and 10 year overall survival was 86% (95% confidence interval 74-92) and 65% (95% confidence interval 50-78), respectively. Seventeen of 62 patients (27%) who were in remission after radical treatment developed recurrence with either local or distant disease. The 5 year recurrence-free survival was 83% (95% confidence interval 70-90) and the 10 year was 69% (95% confidence interval 53-81). The 5 year local recurrence-free survival was 96% (95% confidence interval 86-99) and the 10 year was 92% (95% confidence interval 76-96). The median time to both overall recurrence and local recurrence was 4.3 years. Metastatic or inoperable SFT had a poor prognosis with a median overall survival of 8.4 months (range 3.6-26.4) and a 5 year overall survival of 11% (95% confidence interval 2-30). A further validation of a risk assessment tool (D-score) confirmed that patients classified as high-risk had a significantly decreased overall survival, with a hazard ratio of 3.7 (95% confidence interval 1.1-12.3).

CONCLUSIONS

This study showed that our management and outcome were comparable with other published studies describing SFT and confirmed the value of the D-score as a risk assessment tool. Because of late recurrences, long-term (e.g. 10 years) follow-up for moderate- and high-risk patients is recommended.

Haemangiopericytoma of the greater omentum: a rare tumour requiring long-term follow-up

Haemangiopericytomas (HPC) are highly vascularized tumours located in any part of the body where capillaries can be found. Since 2002, they have been re-classified under the umbrella 'extrapleural Solitary Fibrous Tumour (SFT)' and the term HPC is nowadays used to describe a growth pattern rather than a clinical entity. Their biological behaviour varies and they require a long-term follow-up since they may recur or metastasise several years after successful treatment. We present the case of a gentleman with HPC of the greater omentum initially appeared in 1998. HPC rarely develops in the greater omentum and only 20 cases have been described in the literature till today. Despite complete excision the mass re-appeared in 2011 and 2017, 13 and 19 years after initial treatment. Surgical management included en bloc excision of three lesions along with greater omentum. No further treatment was required.

Preoperative Assessment of Pathologic Subtypes of Meningioma and Solitary Fibrous Tumor/Hemangiopericytoma Using Dynamic Computed Tomography: A Clinical Research Study

BACKGROUND

Solitary fibrous tumors (SFTs)/hemangiopericytomas (HPCs) are highly vascularized tumors well known for malignant, invasive, and highly vascular features. To date, several studies have reported the preoperative imaging findings of SFTs/HPCs. In this study, computed tomography (CT) tumor values acquired from dynamic CT scan were selected to determine the tumor pathology of highly vascular tumors, such as SFTs/HPCs.

METHODS

We conducted a retrospective study on patients with pathologically diagnosed meningiomas and SFTs/HPCs who had undergone a dynamic contrast CT scan. We assessed and compared the CT values of these tumors according to the pathology.

RESULTS

From a total of 34 patients, 30 patients with meningiomas and 4 patients with HPCs were included. The mean CT values of SFTs/HPCs and angiomatous meningioma were statistically significantly higher than those of the other meningioma subtypes (P = 0.003). We also performed receiver operating characteristic curve analyses to detect an appropriate cutoff point for the CT value to differentiate tumor pathology, and the calculated threshold was 161 Hounsfield units (HU) (sensitivity, 100%; specificity, 75%; area under the curve, 0.87; 95%, CI 0.75-0.99).

CONCLUSIONS

This study showed that obtaining a CT value is useful in determining highly vascular tumor pathology preoperatively. When considering neurosurgical extra-axial tumor removal, and when the CT value of tumors is >161 HU, then highly vascular tumors such as SFTs/HPCs or angiomatous meningiomas are likely, and this should be considered prior to surgical intervention and for risk assessment.

Liquid Biopsy in Rare Cancers: Lessons from Hemangiopericytoma

Hemangiopericytoma (HPT) is a rare mesenchymal tumor of fibroblastic type and for its rarity is poorly studied. The most common sites of metastatic disease in patients with intracranial HPT are the bone, liver, and lung, suggestive for an hematogenous dissemination; for this reason, we investigated, for the first time, the presence of circulating tumor cells (CTCs) in hemangiopericytoma patient by CellSearch® and SceenCell® devices. Peripheral blood samples were drawn and processed by CellSearch, an EpCAM-dependent device, and ScreenCell®, a device size based. We found nontypical CTCs by CellSearch system and the immunofluorescence analysis performed on CTCs isolate by ScreenCell demonstrated the presence of single CTCs and CTC clusters. The molecular characterization of single CTCs and CTC clusters, using antibodies directed against EpCAM, CD34, cytokeratins (8, 18, and 19), and CD45, showed a great heterogeneity in CTC clusters. We believe that the present study may open a new scenario in the rare tumors: the introduction of the liquid biopsy and the molecular characterization of circulating tumor cells could lead to personalized targeted treatments and also for rare tumors.

Soft Tissue Solitary Fibrous Tumor: Combined Surgery and Radiation Therapy Results in Excellent Local Control

PURPOSE

To report survival outcomes and local control in patients with solitary fibrous tumors (SFT) treated using surgery and radiation therapy (RT).

METHODS

We reviewed the medical records of 31 consecutive patients definitively treated for SFT with surgery and RT between 1982 and 2012. The median age was 51 years (range, 23 to 88 y) and tumors were evenly distributed between the head and neck (n=9, 29%), trunk (n=10, 32%), and lower extremities (n=9, 29%). The majority of tumors were large (>5 cm) (n=23, 72%). Specimens had a median of 2 mitoses/10 HPF (range, 0 to 8). Nearly half the cases were treated with postoperative RT (n=14, 45%; median dose, 58 Gy) and the other 17 patients (55%) received preoperative RT (median dose, 50 Gy).

RESULTS

Median follow-up time was 59 months (range, 18 to 349 mo). The 5-year rates of local control, overall survival, and distant metastatic-free survival were 100%, 95%, and 92%, respectively. There were no local or nodal relapses and the 10-year complication rate was 6% (n=2).

CONCLUSIONS

Treatment of soft tissue SFT using combined surgery and RT results in excellent local control.

Solitary fibrous tumor of the ilium: A case report

RATIONALE

Solitary fibrous tumors (SFTs) are rare spindle cell tumors that are most commonly found in the mediastinal pleura. Although there are increasingly more reports of extra-pleural SFTs, reports of SFTs in bone are very rare. To our knowledge, a SFT of the ilium has not yet been reported. With low specificity on computer tomograpy and magnetic resonance imaging, SFTs are easily misdiagnosed.

PATIENT CONCERNS

A 33-year-old man visited our hospital due to repeated right ilium pain for 3 months. The pain was dull and bearable, with no hip joint dyskinesia. The relevant physical examinations are negative. The patient was healthy before and had a negative family history. Radiologically, a large mass with inhomogeneous attenuation and intensity and obvious heterogeneous enhancement was misdiagnosed as a giant cell tumor of ilium.

DIAGNOSES

The man was diagnosed as the solitary fibrous tumor of right ilium.

INTERVENTIONS

The patient was performed an "incision biopsy of the right ilium" and "extended resection of tumor".

OUTCOMES

The pathology and immunohistochemistry was confirmed as the solitary fibrous tumors. The patient was followed-up by computed tomography of pelvis in local hospital every 6 mouths, and there is no recurrence and any symptoms.

LESSONS

We learned that the solitary fibrous tumor could locate in the ilium, and when we see imaging manifestations like this case, we should think it may be SFT.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Hemangiopericytoma 11 years later: delayed recurrence of a rare soft tissue sarcoma

Hemangiopericytomas (HPCs) are uncommon tumours. We present the case of a 41-year-old female with multiple resections at different sites over the course of 11 years. The approach considerations, as well as treatment options and prognosis are discussed. A 41-year-old female with two previous resections for intracranial meningeal HPC in 2004 and 2008, as well as adjuvant radiotherapy, presented in 2015 with left intrathoracic and left hip recurrence confirmed by positron emission tomography/computed tomography (PET/CT). She underwent left proximal femur resection/reconstruction and video-assisted thoracoscopic surgery (VATS) resection of the intrathoracic tumour was attempted. She was discharged home on her 4th post-operative day with minimal pain. There were no neurosensory or motor deficits. Any patient who has been diagnosed with HPC in the past who develops new symptoms should be worked up for recurrence, regardless of the length of disease-free interval, as our case study suggested. There has yet to be a standardized follow-up regime due to the rarity of these tumours. HPC remains a rare soft tissue sarcoma with high recurrence rate. Planned VATS evaluation and resection is possible provided complete resection with clear surgical margins can be achieved, as clear surgical margins offer the best chance of survival.

Solitary fibrous tumour of the tongue: a series of four cases

Background:

Solitary fibrous tumour is a soft tissue tumour of mesenchymal origin. It was first described in the pleura and has since been reported in many anatomical locations. Thirteen cases in the tongue have hitherto been reported. A positive CD34 result has traditionally been used to confirm the diagnosis, although this is often non-specific to solitary fibrous tumour. To date, nuclear STAT6 expression has not been reported in solitary fibrous tumour of the tongue.

Method:

This paper presents a further four cases of solitary fibrous tumour of the tongue, the largest series to date. Clinical, histopathological and immunohistochemical findings are detailed, including nuclear STAT6 expression.

Results:

All four cases were positive for CD34; two cases showed nuclear expression of STAT6. The tumours were excised completely and there have been no recurrences in at least one year.

Conclusion:

Solitary fibrous tumour should be considered as a differential diagnosis for tongue swellings, with the potential to recur.

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

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.

Mediastinal Solitary Fibrous Tumor Diagnosed by Endobronchial Ultrasound-Directed Biopsy

BACKGROUND Solitary fibrous tumors of the middle mediastinal space are uncommon and often not discovered until symptoms secondary to compression of adjacent structures occur. Diagnosis requires surgical biopsy and histological tissue analysis. We describe the ECHO appearance of the solitary fibrous tumor and successful non-invasive EBUS diagnosis. This method of diagnosis allowed for surgical planning for resection and allowed us to exclude non-surgical diseases, such as small cell carcinoma. CASE REPORT A 32-year-old man presented to his primary care physician with worsening intermittent chronic chest pain with recent progressive dysphagia, cough, and dyspnea. Physical examination and routine laboratory work-up were unrevealing. Chest radiograph and computed tomography (CT) of the chest revealed a middle mediastinal mass. Flexible bronchoscopy confirmed extrinsic compression of right and left bronchial trees. Endobronchial ultrasound (EBUS) was used to biopsy the mass and the diagnosis of solitary fibrous tumor was confirmed. The patient underwent successful tumor resection and was discharged home after an uneventful postoperative period. CONCLUSIONS Endobronchial ultrasound-directed tissue biopsy is an appropriate modality for suspected solitary fibrous tumors of the mediastinum. To our knowledge, this is only the second reported case of SFT diagnosed by EBUS-TBNA. Our case uniquely demonstrates the advantages of pre-surgical diagnosis of mediastinal masses with EBUS-TBNA when the diagnosis SFT is suggested on CT and US imaging.

Malignant solitary fibrous tumor of the orbit: Spectrum of histologic features

PURPOSE

Primary malignant solitary fibrous tumor (SFT) of the orbit is a rare spindle cell neoplasm that requires excisional biopsy for histopathological diagnosis. We present a clinical case using contemporary immunohistochemical stains, report on the latest World Health Organization classification, and provide a review of the literature.

OBSERVATIONS

Report of a single case of a 65 year old male who presented with right-sided proptosis, limited adduction, ptosis, lateral globe displacement, and cheek festooning. Neuroimaging revealed a 2.2 cm, extraconal heterogeneous mass that diffusely enhanced.En-bloc tumor resection confirmed SFT malignancy based upon nuclear atypia, hypercellularity, and increased mitotic activity (13 mitotic figures/10 high powered fields). Ki-67 showed 2% nuclear staining in the benign tumor and 10-15% staining in the malignant counterpart. Immunohistochemical analysis revealed diffuse Stat6 positivity, CD 34 positivity with partial lack of staining within the malignant portion, S-100 positivity in the malignant portion, and overall negativity for CAM 5.2, desmin, actin, CD 31, and CD 117.

CONCLUSIONS AND IMPORTANCE

Immunoprofiling is helpful to making the diagnosis of malignant solitary fibrous tumor of the orbit. Complete tumor resection continues to be the preferred treatment. The behavior of extrathoracic SFT is unpredictable, and patients with SFT in all locations require careful, long-term follow-up.

Malignant giant solitary fibrous tumor of the pleura metastatic to the thyroid gland

PURPOSE

Solitary fibrous tumor (SFT) of the pleura is a rare mesenchymal neoplasm arising from mesenchymal cells in the areolar tissue subjacent to the mesothelial-lined pleura and accounting for less than 5% of primary pleural tumors. SFTs are generally benign and asymptomatic, with 10-year survival rates of up to 98%. Unfortunately, approximately 10% have malignant potential, leading to local recurrence after radical surgery and/or metastatic spread. Of note, giant pleural SFT, which consists of a tumor occupying at least 40% of the affected hemithorax, is even less common with only anecdotal cases reported in the medical literature.

METHODS

We describe a unique case of giant SFT of the pleura that metastasized to the thyroid gland 1 year after complete resection, focusing on its clinical and pathological features of presentation.

RESULTS

En bloc resection remains the mainstay of therapy with curative intent. Patients with large tumors may undergo preoperative angiography with percutaneous embolization of the tumor, which allows to reduce perioperative bleeding. In case of local recurrence, surgery still remains the best treatment option. However, surgery can also be considered in patients with isolated metastatic spread.

CONCLUSIONS

Every suspected and proven SFT of the pleura should undergo surgical resection, as clinical and radiological criteria cannot accurately distinguish benign from malignant forms. Moreover, the peculiar histological features of SFT should not be neglected when planning clinicoradiological follow-up. Additionally, suspicious clinical findings during follow-up should always be thoroughly investigated in order to exclude or confirm the diagnosis of recurrent disease.

Solitary fibrous tumor of maxilla: A rare entity

Solitary fibrous tumor (SFT) is a ubiquitous rare mesenchymal neoplasm. Pleura is the favored site of origin and is rare in the oral cavity. SFT occurs across a wide histopathologic spectrum. Fibrous form characterized by hyalinized, thick-walled vessels with opened lumina and strong CD34 reactivity constitute one end and on the other end, a cellular form representing the conventional hemangiopericytoma, with branched, thin-walled vessels and focal or negative CD34 reactivity characterize the spectrum. A case of oral SFT in a 30-year-old female patient with its clinical, histopathological and immunohistochemical features is being presented here.

Is a Solitary Fibrous Tumor in the External Auditory Canal Benign?

A solitary fibrous tumor (SFT) is an extremely rare, distinct otological soft-tissue tumor. Only two such tumors in the external auditory canal have been reported. A SFT related to hemangiopericytomas (HPC), which commonly arise in the central nervous system. HPCs act malignant in many cases, while SFTs at other sites are mainly benign. A 25-year-old female presented with highly vascular tumor at the right external auditory meatus and bleeding from the mass when a crust was removed from its surface. After excisional biopsy followed by pre-operative embolization, this tumor confirmed with SFT. The recurrence rate of SFT is very low after complete resection, with a slightly increased risk of recurrence with extrathoracic tumors. We describe the third case of SFT in the external auditory canal and review the literature.