Original ArticleAnalysis of Prognostic Factors, Survival Rates, and Treatment in Anaplastic Hemangiopericytoma
Introduction
Hemangiopericytoma (HPC) is a rare mesenchymal tumor that can occur in any part of the body. HPC was first described in 1942 by Stout and Murray, who proposed it was derived from pericytes, which are modified muscle cells.1 Because there was no clear difference between HPC and anaplastic hemangiopericytoma (AHPC) before 2007, both were described as “WHO grade II–III HPC.” As of 2007, the World Health Organization (WHO) classification for WHO grade II–III HPC recognizes 2 entities: HPC and AHPC.2 AHPCs are biologically aggressive tumors that have a high recurrence rate and poor tumor control.
It was previously shown that glioblastoma could present as either primary (the initial surgery was for glioblastoma) or secondary (progression from a lower-grade glioma),3 and the same course has also been reported for malignant meningioma, which can progress from a lower-grade meningioma or a benign meningioma.4 The concept of progression in HPC has not been previously explored, although we observed that HPC and AHPC clearly develop via a similar pathogenesis. Moreover, little information is available in the literature regarding clinical parameters, such as predictive factors and treatment regimens, for AHPC. In the present study, AHPC patients were classified into the 2 following groups: primary AHPC (the initial diagnosis was AHPC at the first surgery) and secondary AHPC (represented by malignant progression from a lower-grade tumor). We sought to determine whether these 2 groups display distinct clinical behaviors and to analyze the survival rates and factors that predict favorable outcomes in the hopes of providing guidance for the management of AHPC.
Section snippets
Patients
We reviewed 52 cases involving patients who were surgically treated for and pathologically diagnosed with AHPC. All patients were assessed to confirm the pathologic diagnosis. Tumors were classified according to the updated 2007 WHO classification criteria. Twelve patients received initial treatment in another hospital, and their data, including previous medical records, preoperative or postoperative radiography, pathology diagnosis, and treatment history, were retrospectively reviewed. All
Data in Patients with AHPC
In this study, we included 27 male patients (51.9%) and 25 female patients (48.1%). The average age at the time of the first AHPC surgery was 43 years old (range, 4–72 years old). The median preoperative KPS at the time of the initial operation was 90 (range, 50–90). The tumor locations were classified into the following 3 regions: supratentorial (n = 34, 65.4%), skull base (n = 12, 23.1%), and tentorial (n = 6, 11.5%). Symptoms depended mainly on the tumor location, and headache (n = 32,
Discussion
Intracranial HPC is an uncommon neoplasm that accounts for only 1% of all central nervous system tumors.5 In the 2007 WHO classification of brain tumors, HPC is divided into 2 subtypes: grade II (HPC) and grade III (AHPC).2 AHPC is characterized by the presence of >5 mitoses per 10 high-power fields and/or necrosis and must exhibit any 2 of the following traits: hemorrhage, moderate to high nuclear atypia, and moderate to high cellularity. Hemorrhage, necrosis, and cystic degeneration are
Conclusion
Surgery remains the first-choice treatment for AHPC, although extensive intraoperative blood loss increases its operative difficulty. Patients who received adjuvant radiotherapy following resection exhibited better local recurrence and had a higher OS rate. Clinical behaviors were distinct between the 2 groups. In particular, we found that secondary tumors were more likely to result in local recurrence and this increases our understanding of and guides treatment for AHPC.
References (19)
- et al.
Primary intracranial haemangiopericytoma: comparison of survival outcomes and metastatic potential in WHO grade II and III variants
J Clin Neurosci
(2014) - et al.
Intracranial hemangiopericytoma—our experience in 30 years: a series of 43 cases and review of the literature
World Neurosurg
(2014) - et al.
Hemangiopericytoma of the central nervous system: a review of 94 cases
Hum Pathol
(1991) - et al.
Thirty-nine cases of intracranial hemangiopericytoma and anaplastic hemangiopericytoma: a retrospective review of MRI features and pathological findings
Eur J Radiol
(2012) - et al.
Meningeal hemangiopericytomas: long-term outcome and biological behavior
Surg Neurol
(2003) - et al.
Hemangiopericytoma: a vascular tumor featuring Zimmermann's pericytes
Ann Surg
(1942) - et al.
The 2007 WHO classification of tumours of the central nervous system
Acta Neuropathol
(2007) - et al.
Pathways leading to glioblastoma multiforme: a molecular analysis of genetic alterations in 65 astrocytic tumors
J Neurosurg
(1994) - et al.
De novo versus transformed atypical and anaplastic meningiomas: comparisons of clinical course, cytogenetics, cytokinetics, and outcome
Neurosurgery
(2007)
Cited by (0)
Conflict of interest statement: No financial interests or affiliations with institutions, organization, or companies are mentioned or have impacts on the views expressed in the article. There is no conflict of interest.