Descriptive epidemiology of 399 histologically confirmed newly diagnosed meningeal solitary fibrous tumours and haemangiopericytomas in France: 2006-2015.

PURPOSE: Meningeal solitary fibrous tumour (SFT) and haemangiopericytoma (HPC) are uncommon tumours that have been merged into a single entity in the last 2021 WHO Classification of Tumors of the Central Nervous System. To describe the epidemiology of SFT/HPC operated in France and, to assess their incidence. METHODS: We processed the French Brain Tumour Database (FBTDB) to conduct a nationwide population-based study of all histopathologically confirmed SFT/HPC between 2006 and 2015. RESULTS: Our study included 399 SFT/HPC patients, operated in France between 2006 and 2015, in one of the 46 participating neurosurgical centres. The incidence reached 0.062, 95%CI[0.056-0.068] for 100,000 person-years. SFT accounted for 35.8% and, HPC for 64.2%. The ratio of SFT/HPC over meningioma operated during the same period was 0.013. SFT/HPC are about equally distributed in women and men (55.9% vs. 44.1%). For the whole population, mean age at surgery was 53.9 (SD ± 15.8) years. The incidence of SFT/HPC surgery increases with the age and, is maximal for the 50-55 years category. Benign SFT/HPC accounted for 65.16%, SFT/HPC of uncertain behaviour for 11.53% and malignant ones for 23.31%. The number of resection progresses as the histopathological behaviour became more aggressive. 6.7% of the patients with a benign SFT/HPC had a second surgery vs.16.6% in case of uncertain behaviour and, 28.4% for malignant SFT/HPC patients. CONCLUSION: Meningeal SFT and HPC are rare CNS mesenchymal tumours which both share common epidemiological characteristics, asserting their merging under a common entity. SFT/HPC incidence is less that one case for 1 billion per year and, for around 100 meningiomas-like tumours removed, one SFT/HPC may be diagnosed. SFT/HPC are equally distributed in women and men and, are mainly diagnosed around 50-55 years. The more aggressive the tumour, the higher the probability of recurrence.

Orbital myopericytoma: an unusual tumor in an unusual location.

A 71-year-old male with a 4-month history of bulging, tearing, and redness in the right eye presented with vision loss, proptosis, conjunctival hyperemia, and chemosis. Magnetic resonance imaging showed a right intraconal solid mass with extraconal extension, hyper-intense in T2 sequences with heterogeneous contrast enhancement. Complete excision of the mass was performed through a lateral orbitotomy. Histological analysis revealed a neoplasm with high vessel density, solid growth of oval cells, a concentric proliferation of the wall of small vessels, and a weak and patchy positivity for smooth muscle actin. These findings were consistent with the diagnosis of myopericytoma. After surgery, visual acuity improved in the affected eye and after 18 months of follow-up there have been no signs of recurrence.

Presurgical differentiation between malignant haemangiopericytoma and angiomatous meningioma by a radiomics approach based on texture analysis.

PURPOSE: To assess whether a machine-learning model based on texture analysis (TA) could yield a more accurate diagnosis in differentiating malignant haemangiopericytoma (HPC) from angiomatous meningioma (AM). MATERIALS AND METHODS: Sixty-seven pathologically confirmed cases, including 24 malignant HPCs and 43 AMs between May 2013 and September 2017 were retrospectively reviewed. In each case, 498 radiomic features, including 12 clinical features and 486 texture features from MRI sequences (T2-FLAIR, DWI and enhanced T1WI), were extracted. Three neuroradiologists independently made diagnoses by vision. Four Support Vector Machine (SVM) classifiers were built, one based on clinical features and three based on texture features from three MRI sequences after feature selection. The diagnostic abilities of these classifiers and three neuroradiologists were evaluated by receiver operating characteristic (ROC) analysis. RESULTS: Malignant HPCs were found to have larger sizes, slighter degrees of peritumoural oedema compared with AMs (P<0.05), and more serpentine-like vessels. The AUC of the enhanced T1WI-based classifier was 0.90, significantly higher than that of T2-FLAIR-based or DWI-based classifiers (0.77 and 0.73). The AUC of the SVM classifier based on clinical features was 0.66, slightly but not significantly lower than the performances of 3 neuroradiologists (AUC=0.69, 0.70 and 0.73). CONCLUSION: Machine-learning models based on clinical features alone could not provide a better diagnostic performance than that of radiologists. The SVM classifier built by texture features extracted from enhanced T1WI is a promising tool to differentiate malignant HPC from AM before surgery.

WHO 2016 classification: changes and advancements in the diagnosis of miscellaneous primary CNS tumours.

This short review highlights significant changes and recent findings incorporated to varying extent in the WHO 2016 definition of a variety of tumours, including peripheral nerve sheath tumours, meningiomas, mesenchymal nonmeningothelial tumours, melanocytic tumours, lymphomas and histiocytic tumours, germ cell tumours and non-neuroendocrine pituitary tumours. Most notable classification changes include: adding 'hybrid nerve sheath tumours' to the spectrum of benign nerve sheath tumours; an updated definition of atypical meningioma (WHO grade II), including cases with brain invasion; recognizing dural solitary fibrous tumour (SFT) and haemangiopericytoma (HPC) as a single tumour entity characterized by NAB2 and STAT6 gene fusions for which the term SFT/HPC was chosen; recognizing that pituitary granular cell tumour, spindle cell oncocytoma, and pituicytoma all share nuclear expression of TTF-1, possibly representing a spectrum of a single nosological entity derived from posterior pituitary glial cells. The most significant diagnostic markers which have emerged include: inactivation of NF1, CDKN2A, and PRC2 components, SUZ12 and EED in MPNST, leading to neurofibromin and H3K27me3 expression loss; GNAQ and GNA11 mutations in CNS primary melanocytic tumours; BRAFV600E mutation in histiocytic tumours (Langerhans cell histiocytosis and Erdheim-Chester disease) and papillary craniopharyngioma, which provides both a diagnostic marker in the appropriate pathological setting and a therapeutic target. The WHO 2016 Classification has balanced cutting-edge knowledge on the molecular characteristics of the miscellaneous CNS tumours reviewed here with a practical approach for their daily diagnostic work-up. Much more progress can be expected in the classification of these neoplasms in the near future.

Meningeal haemangiopericytoma and solitary fibrous tumour: a retrospective bi centre study for outcome and prognostic factor assessment.

To describe the outcome of patients diagnosed with central nervous system haemangiopericytoma (HPC) or solitary fibrous tumour (SFT) and identify factors that may influence recurrence and survival. Between January 2000 and September 2016, a retrospective search identified 55 HPCs/SFTs. The patients underwent a total of 101 surgical resections and 56.9% received radiation therapy. Median follow-up was 7.8 years. 28 patients (50.9%) were re-operated for tumour recurrence. At the end of the study, 21 patients (42%) had no residual tumour on the last scan. Surgical recurrence-free survival at 5 years was 75.2%, 95% CI [63.3-89.3] and, the median surgical recurrence-free survival was 7.4 years. In the adjusted analysis, venous sinus invasion (present vs. absent) (HR 3.39, 95% CI [1.16, 9.93], p = 0.026), completeness of resection (HR 0.38, 95% CI [0.15-0.97], p = 0.042) and tumour subtype (SFT vs. HPC) (HR 3.02, 95% CI[1.02, 8.91], p = 0.045) were established as independent prognostic factors. At the end of the study, 25 patients were deceased (45.5%). and only 15 patients (27.3%) had no residual tumour on the last scan and were alive. Overall survival at 5 years was 80.2, 95% CI [69.3-92.8] and the median overall survival was 13.1 years. None of the investigated variables was associated with overall survival. Patients who received radiation therapy demonstrated neither a reduced risk of surgical recurrence (p = 0.370) nor a longer overall survival (p = 1.000). SFTs/HPCs are associated with a significant risk of recurrence that may reduce the survival of the patients. Total tumour resection upon initial surgery is associated with a lower risk of relapse but not with a prolonged survival. We did not observe a significant improvement in any of the clinical outcomes after radiation therapy.

Paediatric and adult soft tissue sarcomas with NTRK1 gene fusions: a subset of spindle cell sarcomas unified by a prominent myopericytic/haemangiopericytic pattern.

Neoplasms with a myopericytomatous pattern represent a morphological spectrum of lesions encompassing myopericytoma of the skin and soft tissue, angioleiomyoma, myofibromatosis/infantile haemangiopericytoma and putative neoplasms reported as malignant myopericytoma. Lack of reproducible phenotypic and genetic features of malignant myopericytic neoplasms have prevented the establishment of myopericytic sarcoma as an acceptable diagnostic category. Following detection of a LMNA-NTRK1 gene fusion in an index case of paediatric haemangiopericytoma-like sarcoma by combined whole-genome and RNA sequencing, we identified three additional sarcomas harbouring NTRK1 gene fusions, termed 'spindle cell sarcoma, NOS with myo/haemangiopericytic growth pattern'. The patients were two children aged 11 months and 2 years and two adults aged 51 and 80 years. While the tumours of the adults were strikingly myopericytoma-like, but with clear-cut atypical features, the paediatric cases were more akin to infantile myofibromatosis/haemangiopericytoma. All cases contained numerous thick-walled dysplastic-like vessels with segmental or diffuse nodular myxohyaline myo-intimal proliferations of smooth muscle actin-positive cells, occasionally associated with thrombosis. Immunohistochemistry showed variable expression of smooth muscle actin and CD34, but other mesenchymal markers, including STAT6, were negative. This study showed a novel variant of myo/haemangiopericytic sarcoma with recurrent NTRK1 gene fusions. Given the recent introduction of a novel therapeutic approach targeting NTRK fusion-positive neoplasms, recognition of this rare but likely under-reported sarcoma variant is strongly encouraged.

CD34 + tumours of the orbit including solitary fibrous tumours: a six-case series.

BACKGROUND: To report six cases of CD34+ fibroblastic mesenchymal tumours, which are uncommon neoplasms in the orbit. CASE PRESENTATION: Six patients presenting with proptosis and palpable mass who were later diagnosed with fibrous solitary tumours, fibrous histocytoma or haemangiopericytoma in the orbit were included. All patients received radiologic examinations and surgical excision for histopathology and immunohistochemistry examinations. Five patients had no recurrence after a minimum follow-up of 12 months. One patient (case 6) experienced recurrence twice, and had debulking surgeries each time. At present, the patient still has remnant tumour in the orbit, but no growth has been detected during the past two years. The tumour size will be closely monitored. CONCLUSIONS: Even though fibroblastic tumours are rarely found in the orbit, they can present as a palpable mass with proptosis. Complete surgical excision is important for long-term prognosis, and immunohistochemical study is helpful for confirming pathologic diagnosis.

Tablets at the bedside - iPad-based visual field test used in the diagnosis of Intrasellar Haemangiopericytoma: a case report.

BACKGROUND: In the assessment of a pituitary mass, objective visual field testing represents a valuable means of evaluating mass effect, and thus in deciding whether surgical management is warranted. CASE PRESENTATION: In this vignette, we describe a 73 year-old lady who presented with a three-week history of frontal headache, and 'blurriness' in the left side of her vision, due to a WHO grade III anaplastic haemangiopericytoma compressing the optic chiasm. We report how timely investigations, including an iPad-based visual field test (Melbourne Rapid Field, (MRF)) conducted at the bedside aided swift and appropriate management of the patient. CONCLUSIONS: We envisage such a test having a role in assessing bed-bound patients in hospital where access to formal visual field testing is difficult, or indeed in rapid testing of visual fields at the bedside to screen for post-operative complications, such as haematoma.

The current role of Gamma Knife radiosurgery in the management of intracranial haemangiopericytoma.

BACKGROUND: Haemangiopericytomas (HPCs) are rare tumours characterised by aggressive behaviour with tendency to local recurrence and to metastasise. WHO grade II and grade III tumours show different progression-free survival and overall survival rates. Gross total tumour resection is still considered the treatment of choice. Adjuvant radiation therapies represent an option in the treatment strategy regardless the extent of resection. Based on this consideration, Gamma Knife radiosurgery has been introduced either as a primary treatment or as an adjuvant treatment for residual or recurrent tumours. METHOD: A systematic search was performed on PubMed, Web of Science and Google Scholar for clinical series reporting Gamma Knife radiosurgery, Cyberknife and Linear Accelerator (LINAC) for the management of intracranial HPCs. RESULTS: Fourteen studies focusing on the effects of Gamma Knife radiosurgery for intracranial HPCs were included. Four studies reported data on Cyberknife radiosurgery and LINAC. A total of 208 patients harbouring 366 tumours have been reported. Patient's features, radiosurgical treatment characteristics and follow-up data of the pertinent literature have been critically revised. CONCLUSIONS: Gamma Knife radiosurgery and the other radiosurgical techniques represent a feasible and effective therapy in the management of HPCs. Tumour control and survival rate are comparable to those reported for radiotherapy. Further studies should be focused to define the exact role of Gamma Knife radiosurgery in the management of HPCs.

Haemangiopericytoma of the lacrimal sac.

Haemangiopericytomas (HPCs) are rare tumours which infrequently occur in the lacrimal sac. Only 8 cases of lacrimal sac HPC have previously been reported. The authors report 2 additional cases presenting clinically with epiphora and a mass. One case recurred 3 times during an 18-year period. The other case did not recur during 51 months of follow-up. The tumours showed immunohistochemical features consistent with a diagnosis of HPC. The authors recommend wide excision for these tumours and careful long-term follow-up to detect recurrence which is not uncommon.

Haemangiopericytoma-like tumor of the nasal cavity treated by endoscopy - a case report.

Haemangiopericytoma (HPC) is an uncommon, vascular tumor derived from Zimmerman pericytes surrounding blood vessels. HPC constitute around 1% of all tumors of vascular origin and may appear anywhere, 5% of them can be situated in nasal cavity. Tumor location within the head and neck predispose to its benign character and improves prognosis. This case report presents the case of 33-year-old patient with haemangiopericytoma-like tumor of the nasal cavity, presented symptoms of impaired nasal breathing and recurrent epistaxis. Tumor was excised with 0 degree endoscope. The follow-up recurrence-free period was 2 year 6 months and shows this is effective way of treatment. Described in the literature late recurrences and metastases reminds that regular, life-long observation is mandatory.

Myopericytoma of the posterior cranial fossa.

Myopericytoma is a soft tissue tumour believed to be derived from perivascular myoid cells. They are typically found in subcutaneous tissues in the extremities. Intracranial myopericytomas are exceptionally rare. Here we report a man with an asymptomatic posterior fossa myopericytoma with evidence of dural infiltration.

GRIA2 is a novel diagnostic marker for solitary fibrous tumour identified through gene expression profiling.

AIMS: The NAB2-STAT6 fusion was recently identified as a consistent finding in solitary fibrous tumour (SFT), resulting in nuclear expression of the C-terminal part of STAT6. Gene expression studies of SFT revealed high expression of the GRIA2 gene. The aim of this study was to examine GRIA2 expression in SFTs and other soft tissue tumours to evaluate its diagnostic utility. METHODS AND RESULTS: Immunohistochemistry was performed on 375 soft tissue tumours. In total, 84 of 105 (80%) SFTs, including 86% of malignant SFTs and 100% of dedifferentiated SFTs, were positive for GRIA2. One SFT known to harbour the NAB2-STAT6 fusion but that was negative for STAT6 by immunohistochemistry was positive for GRIA2. It is of note that 93% of SFTs received in the last 3 years were positive for GRIA2, as compared with only 70% of older cases. The only other tumours that expressed GRIA2 were 15 of 20 (75%) cases of dermatofibrosarcoma protuberans (DFSP), four of nine (44%) myoepitheliomas, one synovial sarcoma (<1% of cells), and one schwannoma. CONCLUSIONS: GRIA2 is a useful marker for distinguishing SFT from most mimics. Among other CD34-positive tumours, GRIA2 is also expressed in DFSP; however, clinical and histological features aid in their distinction. GRIA2 shows a limited distribution in other soft tissue tumours.

Phenotypical and molecular distinctness of sinonasal haemangiopericytoma compared to solitary fibrous tumour of the sinonasal tract.

AIMS: Sinonasal haemangiopericytoma (SN-HPC) is a rare sinonasal mesenchymal neoplasm of perivascular myoid cell origin. Solitary fibrous tumour (SFT) occurs only very rarely in the sinonasal tract. SFT and soft tissue HPC have been considered a single entity. Recently, recurrent gene fusions involving NAB2-STAT6 resulting in differential expression of STAT6 were characterized as central molecular events in SFT. However, no data exist for NAB2-STAT6 status or STAT6 expression in SN-HPC. METHODS AND RESULTS: We examined six SN-HPCs and two sinonasal SFTs by immunohistochemistry and RT-PCR for NAB2-STAT6 fusions. SN-HPC affected three females and three males (mean age: 72 years). They expressed smooth muscle actin, lacked strong CD34 reactivity and were negative for nuclear STAT6 expression. RT-PCR analysis confirmed the absence of NAB2-STAT6 fusions in all cases. Conversely, both sinonasal SFTs (in males aged 39 and 52 years) displayed classical features of pleuropulmonary and soft-tissue SFTs (uniformly CD34-positive with strong nuclear expression of STAT6). RT-PCR revealed NAB2-STAT6 fusions in both cases. CONCLUSIONS: These findings confirm the molecular and phenotypical distinctness of these two entities. While SN-HPC is a site-specific sinonasal neoplasm of as yet unknown molecular pathogenesis, sinonasal SFTs show phenotypical and molecular identity to their pleural/extrapleural counterparts.

Solitary fibrous tumour of the urinary bladder - A rare and potentially malignant neoplasm.

Solitary fibrous tumours (SFTs) of the urinary bladder are a rare mesenchymal neoplasm that occasionally has malignant potential. The tumour is characterised by haphazardly arranged spindle-shaped to ovoid cells, with a prominent, branching, thin-walled, dilated vasculature and NAB2-STAT6 gene rearrangement. While most SFTs are indolent in nature, difficulty arises predicting which SFTs are potentially malignant. There are now validated risk stratification tools to help identify which SFTs are likely to metastasize and help clinicians determine management. The mainstay of treatment for SFTs remains surgery, with emerging evidence in the combined use of surgery and radiotherapy.

Surgical Treatment of the Solitary Fibrous Tumour/ Haemangiopericytoma of the External Auditory Canal: A Case Report.

A solitary fibrous tumour (SFT)/haemangiopericytoma (HPC) accounts for approximately 1% of all vascular tumours, and 13-25% of them are present in the head and neck region. Here, a case of SFT in the left EAC has been reported with the longest duration follow-up among the previously reported cases.

Resection of an orbital haemangiopericytoma after direct intraoperative injection of 40% N-butyl-2-cyanoacrylate and 60% Lipiodol.

Haemangiopericytoma is a highly vascular tumour, which is a rare soft tissue lesion that may arise anywhere in the body, including the orbit. During its surgical resection, it is too friable for the surgeon to handle and it can bleed severely causing many problems to the surgeon. That is why many surgical approaches have been reported till now, aiming at total excision with minimal blood loss. In this case, total resection of an orbital haemangiopericytoma in a 61-year-old Caucasian woman, using an intraoperative 23G needle injection of 40% n-butyl-2-cyanoacrylate and 60% lipiodol, is presented. The lesion was directly injected under fluoroscopic visualization, after which it became firm enough to be surgically removed without significant bleeding.

A rare case of sinonasal glomangiopericytoma post operative accidental diagnosis and managment-A case report.

INTRODUCTION: Glomangiopericytoma is a rare neoplasm of low malignant potential. It is a rare type of haemangiopericytoma located in nasal cavity. This neoplasm has good prognosis and complete surgical excision is treatment of choice. This case report is representing one such neoplasm. This reporting is done in line with the SCARE criteria (Agha et al., 2018 [1]). CASE PRESENTATION: We presenting a case of 54 year old male patient from upper socioeconomic status who presented at our institution with history of surgery (endoscopic sinus surgery with Septoplasty) 15 days back. A Final histopathology report suggested glomangiopericytoma. Since primary surgery was not done as per oncologic principals, patient was advised for adjuvant radiation. At our institute patient was evaluated again. Revision surgery was done. Patient was discharged next day. DISCUSSION: Glomangiopericytoma is a rare neoplasm with incidence of less than 0.5% of all neoplasms of sinonasal cavity. Prognosis is very good after complete surgical excision. It often confuses clinicians with nasal polyps. Here also patient was operated initially considering as benign polyposis outside. Patient was re-operated again to ensure the complete clearance. CONCLUSION: This is the typical case of converting dual modality treatment to single modality with the help of knowledge, communication, transparent team work. This also a rare type of neoplasm and by reporting this rare case we are contributing to data pool of nasal tumors where lack of reporting is major obstacle in the formation of uniform treatment guidelines.

Post-operative stereotactic radiotherapy for the treatment of intracranial haemangiopericytoma: 'A Study of Dose and Outcome'.

INTRODUCTION: This study was performed to assess the relationship between tumour response and radiation dose in equivalent 2 Gy per fraction (EQD2). METHOD: A retrospective cohort analysis of 21 patients with a diagnosis of intracranial haemangiopericytoma between 2000 and 2013 was included in this study. A total of 39 lesions were analysed. The equivalent dose in 2 Gy per fraction was calculated by assigning an alpha-beta ratio of 12 Gy. A paired t-test compared dose (EQD2) and tumour response, and as the outcome was binary, a logistic regression analysis was performed. RESULTS: In total, there were 14 cases of progression and 25 cases of non-progression. It was estimated that for a one unit increase in EQD2, the odds of non-progression were increased by a factor of 1.13 (P = 0.026). After adjusting for PTV volume, the estimated effect of EQD2 (min) on tumour response was stronger, with an estimated odds ratio of 1.36 for an increase of one unit and an odds ratio of 21.6 for an increase of 10 units (P = 0.015). The dose range varied with varying PTV volumes. Based on the logistic model, the probability of having non-progression is larger than 50% for EQ2Dmin doses larger than 30-40 Gy, in particular for volumes larger than 3.67 cm3 . CONCLUSION: This study demonstrates that there is a relationship between dose (EQD2) and outcome. With increasing dose, the likelihood of regression is higher. When adjusted for PTV volume, the response appeared stronger. The dose varied significantly with changes in the size of the PTV.

[Remarkable recovery in a patient with intradural extramedullary haemangiopericytoma: a case report and literature review].

Haemangiopericytomas (HPCs) in the spinal canal are extremely rare and have only been infrequently reported. Severe and sustained spinal cord compression resulting from these intraspinal tumours may cause potentially irreversible neurological impairment. We described a rare case of primary intradural extramedullary HPC recovered from serious compression of thoracic spinal cord in a 65-year-old man suffered from a rapidly progressive disease with complete paralysis of the lower limbs. Magnetic resonance imaging (MRI) and spinal angiography exhibited an unusual hypervascular mass, which was confirmed as HPC by pathological examination, in the dorsal aspects of T7 to T8 spine. Total surgical resection was performed followed by adjuvant radiation. Moreover, this patient had been undergoing specific training of lower limbs from the onset of paralysis and continuous rehabilitation was conducted after discharge. Increased strength of his lower limb muscles was shown in the period of follow-up. Remarkably, four years after surgery, this patient was able to walk with sticks. No signs of local recurrence or metastasis occurred. Conclusively, surgical removal is still the preferred treatment for HPC, and adjuvant radiotherapy and/or chemotherapy may help control tumour recurrence or metastasis. Additionally, it is possible that rehabilitation training potentially promotes neurological function recovery to some extent.