Sellar hemangiopericytoma masquerading as pituitary adenoma: an overlooked intriguing case study unveiling a rare surgical conundrum

Hemangiopericytoma (HPC) constitutes less than 1% of all primary central nervous system tumors. It is a vascular neoplasm with potential malignancy that, in rare instances, manifests as a primary lesion within the brain. Typically, it originates from the meninges. Here, we describe an exceptionally uncommon sellar region solitary fibrous tumor/hemangiopericytoma (SFT/HPC) that mimicked a nonfunctional pituitary adenoma.

Introduction and importance

Case presentation

A 54-year-old male was referred to our hospital due to progressive blurred vision in the left eye over the past year. A homogeneous iso-dense extra-axial intrasellar round mass with extension into the suprasellar region, mainly on the left side, along with bony erosion and osteolysis around the sellar region, was observed on a brain computed tomography (CT) scan. Brain magnetic resonance imaging (MRI) revealed a well-defined 251,713 mm mass with iso-signal on T1-weighted images and hypersignal on T2-weighted images, originating from the pituitary gland within the sella turcica. The mass avidly enhanced following Gadolinium injection and adhered to both carotid arteries without vascular compression or invasion. It extended to the suprasellar cistern and compressed the optic chiasm. The diagnosis was nonfunctional pituitary macroadenoma, leading to the decision for Endoscopic Trans-Sphenoidal Surgery (ETSS). A non-sustainable, soft, grayish mass was grossly and totally resected during the operation. Subsequently, there was a significant improvement in visual acuity during the early postoperative period. Histopathologic examination confirmed hemangiopericytoma (WHO grade II).

Conclusion

Due to its malignant nature, hemangiopericytoma should be included in the differential diagnosis of a sellar mass, both from a clinical and morphological perspective.

Hemangiopericytoma of the skull base: A long-term complete response with trimodality treatment

Hemangiopericytoma (HPC) is a rare tumor originating from Zimmerman pericytes. It constitutes less than 1% of all intracranial tumors. Because of the high recurrence rates, radiotherapy (RT) is a vital step in the treatment, but the timing and dose remain uncertain. We presented a 39-year-old patient with a high-grade hemangiopericytoma located at the skull base. The patient presented with a severe headache. Cranial magnetic resonance imaging (MRI) revealed a mass of size of 60 × 50 mm. A subtotal resection was performed that confirmed the diagnosis of HPC. The patient received 66 Gy postoperative RT. Adjuvant sunitinib treatment was initiated after RT. The complete regression was achieved in the third month after RT. The patient has a complete response for 25 months. To our knowledge, this case is one of the rare cases in the literature in which immediate RT and adjuvant chemotherapy were used in combination with surgery. Although HPC is a radio- and chemo-resistant disease, a trimodality treatment approach can provide the patients with a complete response. In particular, patients with high-grade and inoperable tumors and patients who undergo subtotal resection should be evaluated for trimodal therapy.

Efficacy and toxicity of photon, proton, and carbon ion radiotherapy in the treatment of intracranial solitary fibrous tumor/hemangiopericytoma

BACKGROUND

Solitary fibrous tumors (SFT) of the central nervous system are rare and treatment options are not well established. The aim of this study was to evaluate the clinical outcomes of radiotherapy (RT) and re-radiotherapy (re-RT) for de novo intracranial SFT and recurrent intracranial SFT.

METHODS

This retrospective study analyzed efficacy and toxicity of different RT modalities in patients who received radiotherapy (RT) for intracranial SFT at Heidelberg University Hospital between 2000 and 2020 following initial surgery after de novo diagnosis ("primary group"). We further analyzed the patients of this cohort who suffered from tumor recurrence and received re-RT at our institution ("re-irradiation (re-RT) group"). Median follow-up period was 54.0 months (0-282) in the primary group and 20.5 months (0-72) in the re-RT group. RT modalities included 3D-conformal RT (3D-CRT), intensity-modulated RT (IMRT), stereotactic radiosurgery (SRS), proton RT, and carbon-ion RT (C12-RT). Response rates were analyzed according to RECIST 1.1 criteria.

RESULTS

While the primary group consisted of 34 patients (f: 16; m:18), the re-RT group included 12 patients (f: 9; m: 3). Overall response rate (ORR) for the primary group was 38.3% (N = 11), with 32.4% (N = 11) complete remissions (CR) and 5.9% (N = 2) partial remissions (PR). Stable disease (SD) was confirmed in 5.9% (N = 2), while 41.2% (N = 14) experienced progressive disease (PD). 14% (N = 5) were lost to follow up. The re-RT group had 25.0% CR and 17.0% PR with 58.0% PD. The 1-, 3-, and 5-year progression-free survival rates were 100%, 96%, and 86%, respectively, in the primary group, and 81%, 14%, and 14%, respectively, in the re-RT group. Particle irradiation (N = 11) was associated with a lower likelihood of developing a recurrence in the primary setting than photon therapy (N = 18) (OR = 0.038; p = 0.002), as well as doses ≥ 60.0 Gy (N = 15) versus < 60.0 Gy (N = 14) (OR = 0.145; p = 0.027). Risk for tumor recurrence was higher for women than for men (OR = 8.07; p = 0.014) with men having a median PFS of 136.3 months, compared to women with 66.2 months.

CONCLUSION

The data suggests RT as an effective treatment option for intracranial SFT, with high LPFS and PFS rates. Radiation doses ≥ 60 Gy could be associated with lower tumor recurrence. Particle therapy may be associated with a lower risk of recurrence in the primary setting, likely due to the feasibility of higher RT-dose application.

Developing a Nomogram to Stratify Intracranial Solitary Fibrous Tumor Recurrence

RATIONALE AND OBJECTIVES

To develop a nomogram to stratify tumor recurrence (TR) in intracranial solitary fibrous tumors (ISFTs) based on the clinical, radiological, and pathological features.

MATERIALS AND METHODS

A total of 215 patients from Beijing Tiantan Hospital, Capital Medical University and 48 patients from Lanzhou University Second Hospital, diagnosed with ISFT based on histopathological findings, were included. The patients were randomly divided into training and test cohorts at a ratio of 8:2. Information regarding clinical, radiological, and histopathological features, and the clinical outcomes was retrospectively analyzed. Univariate and multivariate analyses were performed using the Cox proportional hazard model for TR in the training cohort. A nomogram incorporating the independent risk factors was developed in the training cohort and validated in the test cohort. Its predictive performance was analyzed using the Harrell C-index. Decision curve analysis (DCA) was used to evaluate the net clinical benefit.

RESULTS

The Harrell C-indices for TR at 3 and 5 years were 0.845 (0.578-0.944) and 0.807 (0.612-0.901) for the test cohort, respectively. In the test cohort, the nomogram provided a net clinical benefit in the DCA over the TR scheme or non-TR scheme. Although postoperative radiotherapy (PORT) was useful for TR prevention, high doses (≥46 Gy) were not superior to lower doses in prolonging the progression-free survival.

CONCLUSION

The nomogram obtained in our study had a good predictive performance and could be used for ISFT patients.

Conditional survival analysis and dynamic survival prediction for intracranial solitary-fibrous tumor/hemangiopericytoma

BACKGROUND

As the form of World Health Organization Central Nervous System (WHO CNS) tumor classifications is updated, there is a lack of research on outcomes for intracranial combined solitary-fibrous tumor and hemangiopericytoma (SFT/HPC). This study aimed to explore conditional survival (CS) pattern and develop a survival prediction tool for intracranial SFT/HPC patients.

METHODS

Data of intracranial SFT/HPC patients was gathered from the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute. The patients were split into training and validation groups at a 7:3 ratio for our analysis. CS is defined as the likelihood of surviving for a specified period of time (y years), given that the patient has survived x years after initial diagnosis. Then, we used this definition of CS to analyze the intracranial SFT/HPC patients. The least absolute shrinkage and selection operator (LASSO) regression and best subset regression (BSR) were employed to identify predictive factors. The Multivariate Cox regression analysis was applied to establish a novel CS-based nomogram, and a risk stratification system was developed using this model.

RESULTS

From the SEER database, 401 patients who were diagnosed with intracranial SFT/HPC between 2000 and 2019 were identified. Among them, 280 were included in the training group and 121 were included in the internal validation group for analysis. Our study revealed that in intracranial SFT/HPC, 5-year survival rates saw significant improvement ranging from 78% at initial diagnosis to rates of 83%, 87%, 90%, and 95% with each successive year after surviving for 1-4 years. The LASSO regression and BSR identified patient age, tumor behavior, surgery and radiotherapy as predictors of CS-based nomogram development. A risk stratification system was also successfully constructed to facilitate the identification of high-risk patients.

CONCLUSION

The CS pattern of intracranial SFT/HPC patients was outlined, revealing a notable improvement in 5-year survival rates after an added period of survival. Our newly-established CS-based nomogram and risk stratification system can provide a real-time dynamic survival estimation and facilitate the identification of high-risk patients, allowing clinicians to better guide treatment decision for these patients.

Impact of extent of resection and postoperative radiotherapy on survival outcomes in intracranial solitary fibrous tumors: a systematic review and meta-analysis

The knowledge of optimal treatments for patients with intracranial solitary fibrous tumor (SFT) is limited, with inconclusive results from previous studies. In this study, we conducted a meta-analysis of relevant studies to identify the prognostic impact of the extent of resection (EOR) and postoperative radiotherapy (PORT) on survival outcomes of patients with intracranial SFT. We searched the Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify relevant studies published till April 2022. Progression-free survival (PFS) and overall survival (OS) were the outcomes of interest. Differences between two cohorts (gross total resection [GTR] vs. subtotal resection [STR] and PORT vs. surgery only) were estimated by calculating hazard ratios. Twenty-seven studies were selected for the meta-analysis, including data of 1348 patients (GTR, n = 819 vs. STR, n = 381 and PORT, n = 723 vs. surgery only, n = 578). Pooled hazard ratios of PFS (1, 3, 5, and 10 years) and OS (3, 5, and 10 years) revealed that the GTR cohort showed sustained superiority over the STR cohort. In addition, the PORT cohort was superior to the surgery-only cohort with respect to all PFS periods. Although the 10-year OS between the two cohorts was not statistically different, PORT showed significantly better 3- and 5-year OS than surgery only. The study findings suggest that GTR and PORT provide significant benefits for PFS and OS. Aggressive surgical resection of tumors to achieve GTR followed by PORT should be implemented as optimal treatments for all patients with intracranial SFT when feasible.

Risk Stratification for Management of Solitary Fibrous Tumor/Hemangiopericytoma of the Central Nervous System

INTRODUCTION

Solitary fibrous tumor/hemangiopericytoma (SFT/HPC) of the central nervous system (CNS) is a rare meningeal tumor. Given the absence of prospective or randomized data, there are no standard indications for radiotherapy. Recently, the NRG Oncology and EORTC cooperative groups successfully accrued and completed the first prospective trials evaluating risk-adapted adjuvant radiotherapy strategies for meningiomas. Using a similar framework, we sought to develop prognostic risk categories that may predict the survival benefit associated with radiotherapy, using two large national datasets.

METHODS

We queried the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results (SEER) databases for all newly diagnosed cases of SFT/HPC within the CNS. Risk categories were created, as follows: low risk-grade 1, with any extent of resection (EOR) and grade 2, with gross-total resection; intermediate risk-grade 2, with biopsy/subtotal resection; high risk-grade 3 with any EOR. The Kaplan-Meier method and Cox proportional hazards regressions were used to determine the association of risk categories with overall and cause-specific survival. We then determined the association of radiotherapy with overall survival in the NCDB, stratified by risk group.

RESULTS

We identified 866 and 683 patients from the NCDB and SEER databases who were evaluated, respectively. In the NCDB, the 75% survival times for low- (n = 312), intermediate- (n = 239), and high-risk (n = 315) patients were not reached, 86 months (HR 1.60 (95% CI 1.01-2.55)), and 55 months (HR 2.56 (95% CI 1.68-3.89)), respectively. Our risk categories were validated for overall and cause-specific survival in the SEER dataset. Radiotherapy was associated with improved survival in the high- (HR 0.46 (0.29-0.74)) and intermediate-risk groups (HR 0.52 (0.27-0.99)) but not in the low-risk group (HR 1.26 (0.60-2.65)). The association of radiotherapy with overall survival remained significant in the multivariable analysis for the high-risk group (HR 0.55 (0.34-0.89)) but not for the intermediate-risk group (HR 0.74 (0.38-1.47)). Similar results were observed in a time-dependent landmark sensitivity analysis.

CONCLUSION

Risk stratification based on grade and EOR is prognostic of overall and cause-specific survival for SFT/HPCs of the CNS and performs better than any individual clinical factor. These risk categories appear to predict the survival benefit from radiotherapy, which is limited to the high-risk group and, potentially, the intermediate-risk group. These data may serve as the basis for a prospective study evaluating the management of meningeal SFT/HPCs.

Effect of Different Treatments for Intracranial Solitary Fibrous Tumors: Retrospective Analysis of 31 Patients

OBJECTIVE

An intracranial solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm with a high predisposition toward recurrence and metastasis. The definition of SFT was updated according to the 2021 World Health Organization (WHO) classification. Given its rarity and resemblance to meningiomas, SFT is often misdiagnosed and there remains a debate on the treatment for it. We provide a retrospective analysis of SFTs and conclude the outcomes of different treatments.

METHODS

Patients who accepted operation and were diagnosed with intracranial SFTs in our hospital were included between 2008 and 2021. The medical records on clinical characteristics and outcomes were summarized for analysis. Cox regressions were used to determine the hazard ratio (HR).

RESULTS

Thirty-one SFT patients were included with a median follow-up time of 67 months. Tumor recurrence was observed in 12 (38.7%) patients, with 1 and 5-year recurrence rates of 6.5% and 22.6%, respectively. In univariate analysis, gross total resection (GTR) was significantly associated with decreased recurrence (P = 0.022), while subtotal resection (STR) (HR = 9.237; P = 0.020) and tumor location of tentorium (HR = 4.692; P = 0.022) were correlated with increased recurrence. In multivariate analysis, GTR (P = 0.040) and GTR plus radiotherapy (GTR + RT) (HR = 0.002; P = 0.020) were associated with reduced recurrence, while STR (HR = 40.835; P = 0.012) was a risk factor for recurrence.

CONCLUSIONS

GTR and postoperative RT are beneficial for preventing tumor recurrence. Larger studies and long-term follow-up are warranted to further identify the effect of postoperative RT.

Intracranial solitary fibrous tumor/hemangiopericytoma: Role and choice of postoperative radiotherapy techniques

Background

Intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a novel rare disease after the 2016 WHO reclassification. Surgery is the main treatment. Postoperative adjuvant radiotherapy is often used, but the effects of different radiotherapy techniques are still unclear. The purpose of this study was to analyze the effects of postoperative radiotherapy (PORT) and different radiotherapy methods on the efficacy of patients with intracranial SFT/HPC.

Materials and methods

We retrospectively analyzed 42 patients with intracranial SFT/HPC who underwent surgical treatment from 2008 to 2022, 20 of whom were treated with postoperative intensity-modulated radiotherapy (IMRT) and 22 with postoperative stereotactic radiosurgery (SRS). The Kaplan–Meier method was used to analyze the disease-free survival (DFS) of all the 42 patients receiving postoperative radiotherapy and the time to progression (TTP) of 22 of these patients experiencing recurrence. A multivariate Cox proportional hazards model was used to detect prognostic factors of survival.

Results

In the analysis of PORT patients, the median DFS was 8.33 years for PORT IMRT patients and 3.04 years for PORT SRS patients. The 10-year DFS incidence was 46.0% in the PORT IMRT group and 27.5% in the SRS group. Among the 22 patients who relapsed, the median TTP of other patients was 1.25 years, of which 3 received radiotherapy alone and 1 received symptomatic treatment, while the median TTP of surgical and surgical combined with radiotheray patients were 1.83 and 2.49 years, respectively (p=0.035).

Conclusion

PORT IMRT could prolong DFS compared with PORT SRS. It indicated that PORT IMRT radiotherapy technology was a feasible option for SFT/HPC. Moreover, TTP results of relapsed patients showed that, surgery and surgery combined with radiotherapy treatments have no significant difference on TTP in relapsed patients, but both of them were better than other treatments.

Toward Better Understanding and Management of Solitary Fibrous Tumor

Solitary fibrous tumor (SFT) comprises a histologic spectrum of soft tissue neoplasms that are characterized by the unique NAB2-STAT6 gene fusion. Changes in diagnostic terminology and site-specific classification over the past few decades have resulted in a disjointed literature. Complete surgical excision with preservation of function remains the mainstay of treatment. New risk stratification systems including risk factors such as mitotic rate, age, tumor size, and presence of necrosis, among others, can be used to predict risk of recurrence or metastasis. Long-term follow-up after surgical resection is recommended. The clinical manifestations, diagnosis, management, and prognosis of SFT are reviewed here.

Clinical outcomes in central nervous system solitary-fibrous tumor/hemangiopericytoma: a STROBE-compliant single-center analysis

Background

Solitary fibrous tumor (SFT) and hemangiopericytoma (HPC) are rare mesenchymal tumors in the central nervous system with a high tendency to relapse, having a significant impact on quality of life (QoL). Due to the rarity of intracranial SFT/HPC, the prognostic factors and optimal treatment remain to be elucidated. Meanwhile, quality of life in patients with intracranial SFT/HPC is seldomly concerned. Thus, we aim to survey about the quality of life and underline some aspects demanding concern in intracranial SFT/HPC treatment through summarizing our case series in recent ten years.

Methods

Patients with intracranial SFT/HPC who underwent surgical resection from January 2009 to June 2019 were included in the study. Clinical features, such as age, gender, and resection extent, were collected. The EuroQol Five Dimensions Questionnaire (EQ-5D) was used to assess the patients’ quality of life (QoL). Prognosis factors related to progression-free survival (PFS) and overall survival (OS) were also evaluated.

Results

Thirty-six patients with a mean follow-up period of 61.6 months (range 13–123 months) were included in this study. Sixteen (44.4%) patients achieved gross total resection (GTR). Fourteen patients (38.9%) with tumor progression experienced adjuvant radiotherapy (11.1%) or Gamma Knife surgery (GKS, 27.8%). According to the 2016 WHO classification, there were 6 (16.7%) grade I SFT/HPC, 11 (30.5%) grade II SFT/HPC, and 19 (52.8%) grade III SFT/HPC. The PFS and OS were 29 months (range 4–96 months) and 38 months (range 4–125 months). The median EQ5D-3 L tariff with or without progression was 0.617 (95% CI 0.470–0.756) and 0.939 (95% CI 0.772–0.977) respectively. Gross total resection (GTR, p = 0.024) and grade I SFT/HPC (p = 0.017) were significantly associated with longer PFS. In multivariate analysis, GTR (HR 0.378, 95% CI 0.154–0.927) and adjuvant therapy (HR 0.336, 95% CI 0.118–0.956) result in significantly longer PFS in patients with SFT/HPC.

Conclusions

Patients underwent GTR and adjuvant therapy had longer PFS. Similarly, patients with lower WHO grade had relatively longer PFS. Therefore, GTR is advocated for the treatment of SFT/HPC. And adjuvant therapy such as GKS could be an alternative treatment for patients who underwent STR or with tumor progression. Further, the QoL decreased in patients with tumor progression and metastasis, and more attention is demanded to the QoL of intracranial SFT/HPC patients.

Does post-operative radiotherapy improve the treatment outcomes of intracranial hemangiopericytoma? A retrospective study

BACKGROUND

Intracranial hemangiopericytoma is a rare disease and surgery is the mainstay treatment. Although postoperative adjuvant radiotherapy is often used, there are no reports comparing different radiotherapy techniques. The purpose of this study is to analyze the impact of post-operative radiotherapy and different radiotherapy technique on the results in patients with intracranial hemangiopericytoma (HPC).

METHODS

We retrospectively reviewed 66 intracranial HPC patients treated between 1999 and 2019 including 29 with surgery followed by radiotherapy (11 with intensity-modulated radiotherapy (IMRT) and 18 with stereotactic radiosurgery (SRS)) and 37 with surgery alone. Chi-square test was used to compare the clinical characteristic between the groups. The Kaplan-Meier method was used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox proportional hazards models were used to examine prognostic factors of survival. We also underwent a matched-pair analysis by using the propensity score method.

RESULTS

The crude local control rates were 58.6% in the surgery plus post-operative radiotherapy group (PORT) and 67.6% in the surgery alone group (p = 0.453). In the subgroup analysis of the PORT patients, local controls were 72.7% in the IMRT group and 50% in the SRS group (p = 0.228). The median OS in the PORT and surgery groups were 122 months and 98 months, respectively (p = 0.169). The median RFS was 96 months in the PORT group and 72 months in the surgery alone group (p = 0.714). Regarding radiotherapy technique, the median OS and RFS of the SRS group were not significantly different from those in the IMRT group (p = 0.256, 0.960). The median RFS were 112 and 72 months for pathology grade II and III patients, respectively (p = 0.001). Propensity score matching did not change the observed results.

CONCLUSION

In this retrospective analysis, PORT did not improve the local control rates nor the survivals. The local control rates after IMRT and SRS were similar even though the IMRT technique had a much higher biological dose compared with the SRS technique.

The risks factor of recurrence after skull base hemangiopericytoma management: A retrospective case series and review of literature

OBJECTIVES

Skull base hemangiopericytomas are rare malignant meningothelial tumors involving anterior, middle, and posterior cranial fossa. The outcome of these tumors is inferior due to aggressive behavior and local recurrence. The study aimed to find out the factors affecting the early recurrence and the late recurrence.

METHODOLOGY

A retrospective study was performed over 15 years, and patients were included from a single neurosurgical unit. A total of 35 patients were recruited for analysis.

RESULTS

Twenty-five (71.4%) cases were in the posterior fossa, four (11.4%) cases in the middle cranial fossa, and three (8.6%) patients in the anterior cranial fossa. Fourteen (40%) cases underwent gross total excision, 21(60%) cases subtotal excision. Follow up available for 32 patients, and the median follow -up duration was 64 months (6-240 months). Progression-free survival for the gross total resection group was 104 months compared to 60 months for subtotal resection (p = 0.07). Nineteen (54.3%) cases had recurrence during follow- up period. Six (17.1%) cases recurrence at 1-year time, five (14.3%) cases at 3-year time, three (8.6%) at 5-yr time, four (11.4%) cases at 10- year time. Seventeen (48.6%) cases received radiotherapy, and 13 cases underwent re-exploration and excision of the tumor. Univariate ordinal logistic regression showed that the extent of resection was associated with 1-year, 3-year and 5-year recurrence. Multivariate ordinal logistic regression showed that only extent of resection (STR) was associated with both early and late recurrence.

CONCLUSIONS

The extent of resection is the main predictor of early and delayed recurrence. Upfront radiation therapy has superior tumor control in skull base location.

The Role of Postoperative Radiotherapy in Intracranial Solitary Fibrous Tumor/Hemangiopericytoma: A Multi-Institutional Retrospective Study (KROG 18-11)

Purpose

To evaluate the role of postoperative radiotherapy (PORT) in intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC).

Methods and Materials

A total of 133 patients with histologically confirmed HPC were included from 8 institutions. Gross total resection (GTR) and subtotal resection (STR) were performed in 86 and 47 patients, respectively. PORT was performed in 85 (64%) patients. The prognostic effects of sex, age, performance, WHO grade, location, size, Ki-67, surgical extent, and PORT on local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated by univariate and multivariate analyses.

Results

The 10-year PFS, and OS rates were 45%, and 71%, respectively. The multivariate analysis suggested that PORT significantly improved LC (p<0.001) and PFS (p<0.001). The PFS benefit of PORT was maintained in the subgroup of GTR (p=0.001), WHO grade II (p=0.001) , or STR (p<0.001). In the favorable subgroup of GTR and WHO grade II, PORT was also significantly related to better PFS (p=0.028). WHO grade III was significantly associated with poor DMFS (p=0.029). In the PORT subgroup, the 0-0.5 cm margin of the target volume showed an inferior LC to a large margin with 1.0-2.0 cm (p=0.021). Time-dependent Cox proportion analysis showed that distant failures were significantly associated with poor OS (p=0.003).

Conclusion

This multicenter study supports the role of PORT in disease control of intracranial SFT/HPC, irrespective of the surgical extent and grade. For LC, PORT should enclose the tumor bed with sufficient margin.

Management of meningeal solitary fibrous tumors/hemangiopericytoma; surgery alone or surgery plus postoperative radiotherapy?

INTRODUCTION

A meningeal solitary fibrous tumor (SFT), also called hemangiopericytoma, is a rare mesenchymal malignancy. Due to anatomic constrains, even after macroscopic complete surgery with curative intent, the local relapse risk is still relatively high, thus increasing the risk of dedifferentiation and metastatic spread. This study aims to better define the role of postoperative radiotherapy (RT) in meningeal SFTs.

PATIENTS AND METHODS

A retrospective study was performed across seven sarcoma centers. Clinical information was retrieved from all adult patients with meningeal primary localized SFT treated between 1990 and 2018 with surgery alone (S) compared to those that also received postoperative RT (S + RT). Differences in treatment characteristics between subgroups were tested using independent samples t-test for continuous variables and chi-square tests for proportions. Local control (LC) and overall survival (OS) rates were calculated as time from start of treatment until progression or death from any cause. LC and OS in groups receiving S or S + RT were compared using Kaplan-Meier survival curves.

RESULTS

Among a total of 48 patients, 7 (15%) underwent S and 41 (85%) underwent S + RT. Median FU was 65 months. LC was significantly associated with treatment. LC after S at 60 months was 60% versus 90% after S + RT (p = 0.052). Furthermore, R1 resection status was significantly associated with worse LC (HR 4.08, p = 0.038). OS was predominantly associated with the mitotic count (HR 3.10, p = 0.011).

CONCLUSION

This retrospective study, investigating postoperative RT in primary localized meningeal SFT patients, suggests that combining RT to surgery in the management of this patient population may reduce the risk for local failures.

Supraorbital Craniotomy for Sellar Solitary Fibrous Tumor: Operative Technique and Literature Review

OBJECTIVE

Solitary fibrous tumors (SFT) are rare, locally aggressive, mesenchymal neoplasms that pose both diagnostic and operative challenges. In this review of the literature, data were collected from all previously described sellar and suprasellar SFTs to date, with special attention paid to presenting symptoms, surgical technique performed, recurrence status, and adjuvant radiotherapy or chemotherapy, among others.

METHODS

A review of prior sellar and suprasellar SFTs was performed. Eleven cases of SFTs in the sellar and suprasellar regions were identified. We considered age and sex, along with case-specific information, such as presenting symptoms, surgical approach taken, number of resections, recurrence information, and adjuvant therapy.

RESULTS

All cases including ours presented with visual deficits, ranging from blurry vision to complete bilateral visual loss. Endocrine hormonal abnormalities occurred in nearly all patients (90%.) Craniotomy was performed more often than endonasal transsphenoidal resection of tumors, 42% versus 33%, respectively.

CONCLUSIONS

SFTs are slow-growing fibroblastic mesenchymal neoplasms that comprise <2% of all intracranial tumors. They are even more infrequently found in the sellar/suprasellar region, with our case being the 12th reported case of such and the first only to use supraorbital craniotomy as a resection strategy. Multimodal therapy consisting of safe gross total resection, radiosurgery, and/or chemotherapy provides the best possible results for these rare and locally aggressive entities.

Intracranial hemangiopericytoma after radiation treatment: first case in the literature

Background: Radiation exposure is a known risk factor for meningioma but there are no data regarding hemangiopericytoma and radiation exposure.Case Description: We report a 29-year-old pineoblastoma patient diagnosed with a hemangiopericytoma at a different location, after a successful surgical excision and adjuvant radiotherapy for the original tumor 4-year prior.Conclusion: Hemangiopericytoma emergence can be seen after radiotherapy.

Intracranial Meningeal Hemangiopericytomas: An Analysis of Factors Affecting Outcome in 39 Cases Managed with Multimodality Treatment

Aim

To retrospectively evaluate the outcome of patients with intracranial meningeal hemangiopericytomas (MHPCs) and to analyze various factors for recurrence and survival in these patients.

Materials and Methods

We retrospectively reviewed the clinical data of 39 patients undergoing microsurgical resection for MHPCs at our institute from 2009 to 2015.

Results

Gross total excision (GTE) was achieved in 27 (69.2%) patients, whereas 12 (30.8%) underwent subtotal excision (STE). A total of 25 patients received radiotherapy (RT) (Conventional RT-15; GKT-10), 21 patients had a low grade tumor, while 18 had an anaplastic variant. Twenty patients (51.3%) developed recurrences and the average recurrence-free survival (RFS) was 56 months (range: 12-180 months). Eight patients (20.5%) died during the study period. The average overall survival (OS) was 77.2 months (range: 36-192 months). Two patients (5.1%) developed systemic metastases during follow-up. Patient age was not found to affect RFS or OS. GTE was associated with prolonged RFS and OS but the impact was not statistically significant (P-values = 0.160 and 0.414, respectively). Low tumor grade was associated with statistically significant longer RFS as well as OS (P-values = 0.049 and 0.013, respectively). Addition of adjuvant RT was associated with statistically significant prolongation of RFS (P value = 0.016); however, it was not associated with statistically significant OS benefits (P-value = 0.758).

Conclusions

Our study suggests that a greater extent of excision, lower tumor grade, and addition of adjuvant RT have a positive impact on both RFS and OS; however, low grade and adjuvant RT were the only factors associated with statistically significant prolongation of RFS and only tumor grade was associated with statistically significant OS benefits.

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.

Hemangiopericytoma/Solitary Fibrous Tumor in the central nervous system. Experience with surgery and radiotherapy as a complementary treatment: A 10-year analysis of a heterogeneous series in a single tertiary center

Hemangiopericytoma and Solitary Fibrous Tumor are tumors with low incidence. They have a tendency to recur locally and to metastasize. The WHO integrated both tumors into a new entity but one of the pending issues is to demonstrate the effectiveness of surgery plus complementary radiotherapy (RT) and standardize the use of it. We reviewed the data from 10 years. We assessed pathologic and radiologic characteristics. The operation records were evaluated to determine the features and extent of tumor resection. We compared the outcomes in patients using or not RT. The mean follow-up was 74.8 months, with a range of 12 and 210 months. The population included 3 males (30%) and 7 females (70%). The most common location was brain convexity (30%), the remaining were cervical and lumbar spine, sacrum, intraventricular, torcular, sphenoid ridge and intraorbital. Postoperative external beam radiotherapy was delivered in 7 patients (70%), the criteria were a partial resection or WHO II and III histological grades. 2 patients developed local recurrences at 12 and 19 months after initial surgery. 1 patient underwent 2 surgeries, and the other, 4 surgeries. The mean recurrence free survival rate was 15.5 months. Distant metastases were found in 4 patients. 3 of the 10 patients died. Five-year overall survival rate was 66% and mean overall survival was 76 months. A safe and complete resection in the first surgery is the most important prognostic factor. Complementary RT can be helpful, even in cases of complete resection in WHO low-grade.

Intracranial anaplastic hemangiopericytoma presenting with simultaneous extra-cranial metastases: A case report and review of the literature

Background:

Intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a rare mesenchymal tumor with a propensity to recur and metastasize extracranially years after treatment. Accordingly, there are no reported cases of a patient presenting with a simultaneous intracranial primary and extracranial metastases. We present the case of a patient presenting with an intracranial SFT/HPC and simultaneous liver metastases and propose a treatment paradigm.

Case Description:

A 74-year-old male smoker presented with confusion. An MRI of the brain revealed a heterogeneously enhancing left frontal extra-axial mass. Systemic workup revealed multiple small liver lesions concerning for metastases. The patient underwent gross total resection (GTR) of the intracranial lesion with adjuvant CyberKnife stereotactic radiotherapy to the resection cavity. Pathology was consistent with a WHO Grade III SFT/HPC (previously known as anaplastic HPC). The liver lesions were biopsied and confirmed to be metastases. They were subsequently treated with stereotactic body radiation therapy, temozolomide, and bevacizumab. Eighteen months postoperatively, the patient is alive with no evidence of intracranial malignancy and regression of the hepatic lesions.

Conclusion:

Several studies support GTR and adjuvant radiotherapy to treat intracranial SFT/HPC. The role of adjuvant chemotherapy is less clear. Metastatic disease is typically detected several years after the initial diagnosis, and there is no consensus regarding the optimal treatment strategy. We propose that the rare presentation of intracranial SFT/HPC with simultaneous extracranial metastases should be treated in a multidisciplinary fashion with surgical resection, adjuvant radiotherapy, and chemotherapy.

Spinal location is prognostic of survival for solitary-fibrous tumor/hemangiopericytoma of the central nervous system

BACKGROUND

Prior studies have highlighted infratentorial tumor location as a prognostic factor for solitary fibrous tumor (SFT) and hemangiopericytoma (HPC) of the central nervous system (CNS), and spinal location is considered a positive prognostic factor for other tumors of the CNS. While SFT/HPC of the CNS is known to frequently arise from the spinal meninges, there are no case series that report outcomes for spinally located CNS tumors, and their prognosis in relation to intracranial and other CNS-located tumors is unknown.

OBJECTIVE

To investigate outcomes for patients with SFT/HPC of the spinal meninges.

METHODS

The Surveillance, Epidemiology, and End-Results Program was used to identify patients with SFT/HPC within the CNS from 1993-2015. We retrospectively analyzed the relationship between tumor location (spinal vs. Brain and other CNS) and survival.

RESULTS

We identified 551 cases of CNS SFT/HPC, 64 (11.6%) of which were primary tumors of the spinal meninges. Spinal tumors were more likely than brain and other CNS tumors to be SFT vs. HPC (37.5 vs. 12%, p < 0.001), benign (42.2 vs. 20.3%, p < 0.001), and less than 5 cm (53.1 vs. 35.7%, p < 0.001). The 10-year survival rates for spinal and brain/other CNS tumors were 85 and 58%, respectively. Median survival time was significantly longer for spinal tumors (median survival not reached vs. 138 months, p = 0.03, HR = 0.41 [95% CI 0.18-0.94]). On multivariable analysis, spinal tumor location was associated with improved survival over tumors located in the brain and other CNS (HR = 0.36 [95% CI 0.15-0.89], p = 0.03).

CONCLUSION

Spinal tumor location is associated with improved survival in patients with SFT/HPC of the CNS. Larger institutional studies are necessary to characterize the relationship between tumor location and other relevant factors such as presentation and amenability to gross-total resection and adjuvant radiotherapy. Future studies exploring optimal management of spinally located tumors are also needed.

Clinical outcomes of intracranial solitary fibrous tumor and hemangiopericytoma: analysis according to the 2016 WHO classification of central nervous system tumors

OBJECTIVEThe authors conducted this retrospective study to investigate the clinical outcomes of intracranial solitary fibrous tumor (SFT) and hemangiopericytoma (HPC), defined according to the 2016 WHO classification of central nervous system (CNS) tumors.METHODSHistopathologically proven intracranial SFT and HPC cases treated in the period from June 1996 to September 2014 were retrospectively reviewed and analyzed. Two neuropathologists reviewed pathological slides and regraded the specimens according to the 2016 WHO classification. Factors associated with progression-free survival (PFS) and overall survival (OS) were statistically evaluated with uni- and multivariate analyses.RESULTSThe records of 47 patients-10 with SFT, 33 with HPC, and 4 with anaplastic HPC-were reviewed. A malignant transition from conventional SFT to WHO grade III SFT/HPC was observed in 2 cases, and 13 HPC cases were assigned grade III SFT/HPC. Mean and median follow-ups were 114.6 and 94.7 months, respectively (range 7.1-366.7 months). Gross-total resection (GTR) was significantly associated with longer PFS and OS (p = 0.012 for both), and adjuvant radiation therapy versus no such therapy led to significantly longer PFS (p = 0.018). Extracranial metastases to the liver, bone, lung, spine, and kidney occurred in 10 patients (21.3%). Grade III SFT/HPC was strongly correlated with the development of extracranial metastases (p = 0.031).CONCLUSIONSThe 2016 WHO classification of CNS tumors reflected the different types of pathological malignant progression and clinical outcomes better than prior classifications. Gross-total resection should be the primary treatment goal in patients with SFT/HPC, regardless of the pathological grade, and radiation can be administered as adjuvant therapy for patients with SFT/HPC that shows an aggressive phenotype or that is not treated with GTR.

Pathological prognostic markers in central nervous system solitary fibrous tumour/hemangiopericytoma: Evidence from a small series

Background

Primary central nervous system (CNS) solitary fibrous tumour/hemangiopericytoma (SFT/HPC) is a rare neoplasm and its classification criteria have been redefined by the latest WHO Classification of CNS Tumours. Outcome can vary significantly among patients, thus reliable prognostic markers are warranted.

Methods

Primary CNS SFT/HPC diagnosed at the Pathology Unit of our Institution between 2006 and 2016 were retrospectively collected. Tumour grade along with immunohistochemistry for Ki67, STAT6, PHH3, CD34 and Bcl-2 were assessed. TERT promoter status was evaluated by Sanger sequencing.

Results

Fifteen SFT/HPC were analysed: 9/15 (60%) female, median age at diagnosis 60 (range: 10–67). Six (40%) cases showed a SFT phenotype and mean H&E-mitotic count was 4.8/10 HPF. Tumour grade was I in 6, II in 4 and III in 5 cases. Mean PHH3-mitotic count was higher than H&E count (8.4 versus 4.8/10 HPF), but it would have determined a change in tumour grade in a sole case. Nuclear staining for STAT6 was present in 14/15 (93.3%). CD34 and Bcl-2 expression rates were lower in higher grade tumours. TERT promoter was mutated in two cases. Median follow up time was 2.4 years (6 months-7.4 years) and 5/15 (33%) patients developed local disease recurrence. Partial resection (p = 0.0185), higher WHO grade (p = 0.038), lower CD34 (p = 0.038) and Bcl-2 (p = 0.010) expressions were significantly associated with a poorer disease-free interval.

Conclusions

WHO grade is the main prognostic tool in CNS SFT/HPC, but it could be integrated by other markers, like CD34 and Bcl-2, in the clinical practice. The relevance of TERT promoter mutations in this subset of CNS tumours needs further evaluation.

Endoscopic Transnasal Resection of Solitary Fibrous Tumor in the Optic Canal

BACKGROUND

Tumors extending into the optic canal can cause progressive visual impairment because of optic nerve compression. Prompt surgical resection is often necessary. When the tumor is located medially in the optic canal, endoscopic transnasal surgery provides a safer, less invasive alternative to a transcranial approach.

CASE DESCRIPTION

We recently encountered a case of small solitary fibrous tumor in the optic canal causing rapid visual deterioration. The radiographic findings of preoperative imaging studies were compatible with those of meningioma; however, unlike meningioma, bleeding from the tumor was profuse during the operation. The endoscopic transnasal approach was effective for handling the highly vascularized tumor in this delicate region, and gross total removal was achieved with postoperative gradual improvement in his visual function. Nevertheless, the tumor recurred after 6 months, and re-resection was performed using the same surgical corridor, followed by adjuvant radiotherapy.

CONCLUSIONS

Endoscopic transnasal surgery is a valuable option for aggressive lesions in the optic canal. Although the efficacy of radiotherapy for solitary fibrous tumor remains controversial, it should be considered when the tumor shows progressive features.

Grading of meningeal solitary fibrous tumors/hemangiopericytomas: analysis of the prognostic value of the Marseille Grading System in a cohort of 132 patients

The finding that meningeal solitary fibrous tumors (SFTs) and meningeal hemangiopericytomas (HPCs) are both characterized by NAB2-STAT6 gene fusion has pushed their inclusion in the WHO 2016 Classification of tumors of the central nervous system (CNS) as different manifestations of the same entity. Given that the clinical behavior of the CNS SFT/HPC spectrum ranges from benign to malignant, it is presently unclear whether the grading criteria are still adequate. Here, we present the results of a study that analyzed the prognostic value of an updated version of the Marseille Grading System (MGS) in a retrospectively assembled cohort of 132 primary meningeal SFTs/HPCs with nuclear overexpression of STAT6. The median patient follow-up was 64 months (range 4-274 months); 73 cases (55%) were MGS I, 50 cases (38%) MGS II and 9 cases (7%) were MGS III. Progression-free survival (PFS) and disease-specific survival (DSS) were investigated using univariate analysis: the prognostic factors for PFS included MGS, extent of surgery, radiotherapy, chemotherapy and mitotic activity ≥5/10 high-power field (HPF). Moreover, MGS, radiotherapy, mitotic activity ≥5/10 HPF, and necrosis were the prognostic factors measured for DSS. In multivariate analysis, extent of surgery, mitotic activity ≥5/10 HPF, MGS I and MGS III were the independent prognostic factors measured for PFS while necrosis, MGS III and radiotherapy were the independent prognostic factors for DSS. In conclusion, our results show that assessing the malignancy risk of SFT/HPC should not rely on one single criterion like mitotic activity. Therefore, MGS is useful as it combines the value of different criteria. In particular, the combination of a high mitotic activity and necrosis (MGS III) indicates a particularly poor prognosis.

Radiation Therapy as Sole Management for Solitary Fibrous Tumors (SFT): A Retrospective Study From the Global SFT Initiative in Collaboration With the Sarcoma Patients EuroNet

PURPOSE

Solitary fibrous tumors (SFTs) are extremely rare mesenchymal malignancies. Given the lack of large prospective studies on radiation therapy (RT) with definitive and/or palliative intent in SFT patients, this retrospective study aimed to better define the benefit of RT in this disease.

METHODS AND MATERIALS

A retrospective observational study was performed across 7 sarcoma centers. Clinical information was retrieved from all patients receiving RT without surgery over the course of their locally advanced and/or metastatic disease. Differences in treatment characteristics between subgroups were tested using analysis-of-variance tests. Local control (LC) and overall survival (OS) rates were calculated as time from the start of RT until local progression and death from any cause, respectively.

RESULTS

Since 1990, a total of 40 patients were identified. RT was applied with definitive intent in 16 patients and with palliative intent in 24. The median follow-up period was 62 months. In patients treated with definitive RT (receiving approximately 60 Gy), the objective response rate was 67%. At 5 years, the LC rate was 81.3%, and the OS rate was 87.5%. In the case of palliative RT (typically 39 Gy), the objective response rate was 38%. The LC and OS rates at 5 years were 62.5% and 54.2%, respectively. In both subgroups, RT-associated toxicities were mild with predominantly grade 1 acute and late side effects.

CONCLUSIONS

This retrospective study suggests a clinically meaningful benefit for RT given with either definitive or palliative intent without surgery in SFT management. Prospective registries potentially in collaboration with patient advocacy groups are warranted to further assess the role of RT in patients with this rare malignancy.

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.

Analysis of Prognostic Factors, Survival Rates, and Treatment in Anaplastic Hemangiopericytoma

OBJECTIVE

In this study, we aimed to identify prognostic factors in anaplastic hemangiopericytoma (AHPC) and clinical behaviors that differentiate primary and secondary AHPC.

METHODS

The clinical data associated with 52 cases of AHPC that were surgically treated between 2008 and 2015 were reviewed. The patients were classified into the following 2 groups: primary AHPC (AHPC diagnosed at the first surgery) and secondary AHPC (malignant transformation from a lower-grade tumor).

RESULTS

The study included 27 men and 25 women. The participants had a mean age of 43 years old. The 3- and 5-year progression-free survival (PFS) rates were 63.4% and 53.5%, respectively, and the corresponding overall survival rates were 78.7% and 70.9%, respectively. At the final follow-up, there were 22 (42.3%) recurrences, 4 (7.7%) extracranial metastases, and 11 (21.2%) deaths. On the basis of multivariate analysis, primary AHPC (hazard ratio [HR] = 0.293, 95% CI 0.122-0.705) and postoperative radiotherapy (PRT) (HR = 0.372, 95% confidence interval [CI] 0.148-0.932; P = 0.035) were significantly associated with increased PFS, and gross total resection (HR = 3.512, 95% CI 1.060-11.634; P = 0.040) and PRT (HR = 0.165, 95% CI 0.035-0.771; P = 0.022) were independent favorable factors for overall survival.

CONCLUSION

Gross total resection and PRT following surgery are recommended in AHPC. Identifying clinical behaviors that differentiate primary and secondary AHPC improved our understanding of this type of tumor and guided treatment strategies.

Hemangiopericytomas in the Central Nervous System: A Multicenter Study of Korean Cases with Validation of the Usage of STAT6 Immunohistochemistry for Diagnosis of Disease

BACKGROUND

Hemangiopericytoma (HPC) in the central nervous system (CNS) is a rare disease with distinctive biological/clinical characteristics compared with meningioma.

METHODS

Cases of HPCs of the CNS were collected, and clinicopathological records were retrospectively reviewed and analyzed. Immunohistochemistry (IHC) for proliferative markers (Ki-67, PHH3) and STAT6 were performed.

RESULTS

A total of 140 cases were collected, with mean follow-up of 77 months (median 58.8 months; range 0.53-540.5 months). 1-, 5-, 10-, and 20-year survival rates were 99.1, 94.0, 74.4, and 61.9 %, respectively. Thirty-nine patients (27.9 %) had recurrent disease. Mean and median times to recurrence were 62.9 and 47.3 months with 1-, 5-, 10-, and 20-year recurrence-free survival rates of 98.3, 78.3, 50.1, and 11.0 %, respectively. Thirteen patients (9.3 %) developed extracranial metastases. No adjuvant radiation therapy, higher histologic grades, failure of gross-total resection, and cases with gamma-knife surgery (GKS) were factors associated with shorter disease-free survival (log-rank test, p = 0.02, 0.00, 0.02, 0.00), among which high histologic grade and cases with GKS were significant in multivariable analysis. Strong nuclear STAT6 expression was noted in HPCs in 62 cases of HPCs (60/62, 96.8 %), whereas diffuse weak positivity was demonstrated in all meningioma cases.

CONCLUSIONS

The survival rate in patients with HPC of the CNS is comparable to that of previously reported series. Recurrence remains a critical clinical issue of the disease. Identification of NAB2-STAT6 fusion transcript with surrogate IHC marker is a valuable diagnostic tool in the differential diagnosis of the disease.

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.

Intraventricular Hemangiopericytoma: A Case Report and Literature Review

BACKGROUND

Hemangiopericytomas are rare intracranial neoplasms that generally occur in the fifth decade of life and are commonly dural-based, supratentorial tumors. They are classified as World Health Organization grade II or III because of their aggressive nature with high rates of local recurrence and distant metastasis. This case is of an intraventricular hemangiopericytoma in a 23-year-old man. Intraventricular locations are rare, with only 10 cases reported in the literature. Our patient is the youngest to be diagnosed with an intraventricular hemangiopericytoma outside a pediatric case discovered at autopsy.

CLINICAL PRESENTATION

A 23-year-old man with a left intraventricular hemangiopericytoma presenting with headache, word-finding difficulties, blurred vision, nausea, vomiting, photophobia, and right-sided weakness and numbness. Using a left superior parietal lobule approach, a piecemeal resection was completed, achieving radiographic gross total resection. Pathology was consistent with a hemangiopericytoma. He was treated adjunctively with 60 Gy of local radiation. At 6-month follow-up, the patient had resolution of his aphasia and improvement in his headaches, with no signs of recurrence or metastasis on imaging.

CONCLUSIONS

Standard treatment for central nervous system hemangiopericytoma includes aggressive surgical resection. The role of adjuvant radiation is less well defined but is commonly pursued postoperatively. Regardless of extent of resection or adjuvant treatment, close follow-up to evaluate for evidence of local recurrence and distant metastasis is essential.

Tumor-Induced Osteomalacia: an Up-to-Date Review

Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome resulting in renal phosphate wasting and decreased bone mineralization. TIO is usually induced by small, slowly growing tumors of mesenchymal origin (phosphaturic mesenchymal tumor mixed connective tissue variant [PMTMCT]). Nonspecific symptoms including fatigue, bone pain, and musculoskeletal weakness make the diagnosis elusive and often lead to a delay in treatment. The prognosis of TIO is excellent following complete resection of the neoplasm, which leads to the rapid and complete reversal of all symptoms. If the tumor cannot be detected, treatment relies on supplementation with phosphate and active vitamin D compounds. Subsequent radiotherapy in case of incompletely resected tumors or definitive radiotherapy in unresectable tumors is an important treatment option to avoid recurrence or metastasis even though this occurs rarely. Due to the risk of recurrence or late metastases, long-term monitoring is required even in TIO patients diagnosed with a benign tumor.

Intracranial Hemangiopericytomas : A Retrospective Study of 15 Patients with a Special Review of Recurrence

OBJECTIVE

Although surgical resection is used to treat meningeal hemangiopericytoma (MHPC), there is a high risk of subsequent recurrence. This study investigated factors associated with treatment outcomes and recurrence in patients who had undergone surgical resection of intracranial MHPC.

METHODS

Fifteen patients underwent surgical treatments performed by one senior neurosurgeon between 1997 and 2013. Clinical data, radiologic images, surgical outcomes, recurrence, and other relevant characteristics were reviewed and analyzed.

RESULTS

Fifteen patients were included in the analysis, 12 (80%) of whom had tumors in the supratentorial region, and 3 (20%) of whom had tumors in the infratentorial region. Complete resection was achieved in all 15 patients, and 3 (20%) patients were administered radiosurgery and conventional radiotherapy after surgery as adjuvant radiotherapy. Three patients developed recurrence, 2 of whom had not received adjuvant radiotherapy. In 1 of the patients who had not received adjuvant radiotherapy, recurrence developed at the original tumor site, 81 months after surgery. The other 2 recurrences occurred at other sites, 78 and 41 months after surgery. The 5- and 10-year overall survival rates were 88.3%, while the 5- and 10-year recurrence-free survival rates were 83% and 52%, respectively. Additionally the mean Ki-67 index differed significantly between patients who did and did not develop recurrence (43% vs. 14%; p=0.001).

CONCLUSION

Because of the high risk of MHPC recurrence, MHPC tumors should be completely resected, whenever feasible. However, even when complete resection is achieved, adjuvant radiotherapy might be necessary to prevent recurrence.

Multimodal treatment and management strategies for intracranial hemangiopericytoma

Intracranial hemangiopericytoma (HPC) is a rare malignant meningothelial tumor. The authors retrospectively reviewed the long-term clinical outcomes of patients with HPC with regard to treatment modalities and histopathological grades. Eighteen women and 20 men (mean age 38.5 years, range, 18-62 years) were observed over an average follow-up period of 61 months (range, 15-133 months) between 2003 and 2013. The initial treatment modalities included total tumor resection followed by conventional radiotherapy (RT) (n=27), and subtotal tumor resection followed by stereotactic radiosurgery (n=11). One patient (3%) had permanent neurological deficits, and six patients (16%) died. Thirteen patients (34%) suffered recurrence. One year, 5 year, and 10 year recurrence-free survival rates were 100%, 70%, and 39%, respectively. Five patients (13%) developed metastasis. One year, 5 year, and 10 year metastasis-free survival rates were 100%, 89%, 74%, respectively. Low grade tumors were associated with longer overall survival, recurrence-free interval and metastasis-free interval (log-rank, p<0.05). Radical resection with RT was associated with longer overall survival and recurrence-free interval (log-rank, p<0.05), but had no effect on the metastasis-free interval (log-rank, p=0.245). Thus, radical surgery followed by adjuvant RT is the primary treatment of HPC, but recurrence and metastasis remain a common treatment outcome regardless of initial strategy. It is necessary to maintain long-term follow-up and serial imaging for all patients with intracranial HPC after treatment, regardless of extent of resection.

Intracranial hemangiopericytoma--our experience in 30 years: a series of 43 cases and review of the literature

OBJECTIVE

Meningeal hemangiopericytoma (HPC) is a rare, aggressive central nervous system tumor that tends to invade locally and to metastasize, and has a high rate of recurrence.

METHODS

This study presents a retrospective review of patients managed for intracranial HPC at Rome University Hospital.

RESULTS

A total of 43 patients with intracranial HPC were treated from 1980 to 2010. Treatment and follow-up information was available for analysis on 36 patients. The median survival for all patients was 83.5 months after date of diagnosis, with 1-year, 5-year, and 10-year survival rates of 100%, 94.4%, and 72.2%, respectively. Eighteen patients (41.86%) had HPC recurrence. The median time until recurrence was 72.24 months, with 1-year, 5-year, and 10-year progression-free survival rates of 98%, 51%, and 29%, respectively. Five patients (11.62%) developed extracranial metastasis. Patients undergoing any form of adjuvant radiation treatment, including external beam radiotherapy, Gamma Knife radiosurgery, and/or proton beam therapy, had no longer median overall survival (OS) (178 vs. 154 months, respectively; P = .2); but did have a significantly improved recurrence-free interval (108 vs. 64 months; P = .04) compared with patients who did not undergo radiation treatment. Tumor characteristics associated with earlier recurrence included size ≥7 cm (log-rank, P < .05) and sinus invasion (log-rank, P < .05).

CONCLUSIONS

Strategies combining adjuvant radiation with tumor resection seemed to hinder tumor progression, but had no effect on OS or the development of metastases. Greater extent of resection was associated with increased OS (log-rank, P < .05). Anaplastic HPC was associated with reduced OS and with reduced recurrence interval (log-rank, P < .05).

Clinical analysis of intracranial hemangiopericytoma

Objective

Intracranial hemangiopericytomas (HPCs) are rare tumors with aggressive behavior, including local recurrence and distant metastasis. We conducted this retrospective study to evaluate the efficacy of grossly total resection and adjuvant radiotherapy (RT) for these tumors.

Methods

A total of 13 patients treated for intracranial HPC from January 1995 through May 2013 were included in this retrospective study. We analyzed the clinical presentations, radiologic appearances, treatment results, and follow-up outcomes, as well as reviewed other studies.

Results

The ages of the patients at the time of diagnosis ranged from 26 to 73 years (mean : 48 years). The majority of the patients were male (92.3%), and the majority of the tumors were located in the parasagittal and falx. The ratio of intracranial HPCs to meningiomas was 13 : 598 in same period, or 2.2%. Seven patients (53.8%) had anaplastic HPCs. Nine patients (69.2%) underwent gross total tumor resection in the first operation without mortality. Eleven patients (84.6%) underwent postoperative adjuvant RT. Follow-up period ranged from 13 to 185 months (mean : 54.3 months). The local recurrence rate was 46.2% (6/13), and there were no distant metastases. The 10-year survival rate after initial surgery was 83.9%. The initial mean Karnofsky performance scale (KPS) was 70.8 and the final mean KPS was 64.6.

Conclusion

Gross total tumor resection upon initial surgery is very important. We believe that adjuvant RT is helpful even with maximal tumor resection. Molecular biologic analyses and chemotherapy studies are required to achieve better outcomes in recurrent intracranial HPCs.