A case of solitary fibrous tumor/hemangiopericytoma in the central nervous system with papillary morphology

Abstract

This report describes the clinicopathological findings of a solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) of the central nervous system in a 59‐year‐old man with space‐occupying lesions on both the left anterior basicranial and on the top tail of falx cerebri. The tumor showed small quantities of solid papillary areas and a prominent papillary structure, where atypical cells were compactly arranged along the fibrovascular core. The tumor cells of both components showed nuclear relocalization of the signal transducer and activator of transcription 6 protein, with very high specificity and sensitivity for the diagnosis of SFT/HPC. In the literature, only three cases of SFTs with a papillary pattern have been reported, but this case showed a complete papillary pattern. “Papillary” SFT/HPC is a rare morphological variant of SFTs/HPCs, and its differential diagnosis among intracranial tumors is an important factor which clinicians should bear in mind during diagnosis.

Papillary variant of hemangiopericytoma – a rare morphological variant presenting as a recurrent occipital tumor

“…The patient underwent resection of tumor followed by radiation [2]. Our case also showed predominantly papillary pattern with increased mitoses (8-10/10hpf).…”

“…The tumors with HPC phenotype have a high rate of recurrence (> 75% at 10 years) and may develop extracranial metastases, especially in bones, lungs, and liver (in 20% of cases) [1], hence these tumors with a HPC phenotype are considered malignant and are sub classified as grade II or grade III (anaplastic), depending on the mitotic count (<5 vs. >5 mitoses per 10 high-power fields (HPFs) [2]. The parameters of prognostic significance include large size, location, and extent of resection.…”

“…The presence of papillary architecture is very rare in these tumors and only four cases with HPC with papillary structures have been reported in the literature [2,5,15,16].…”

“…CD34 was positive and STAT6 showed nuclear expression which was also confirmed by detection of NAB2 exon6-STAT6 exon 17 using reverse transcription-polymerase chain reaction (RT-PCR). Cao et al [2] reported a case of SFT/HPC of CNS with papillary morphology in a 59 year old patient, with a basifrontal lesion.…”

“…Solitary fibrous tumor / Hemangiopericytoma (SFT/ HPC) of central nervous system is a mesenchymal tumor of fibroblastic type, often showing a rich branching vascular pattern, encompassing a histological spectrum of tumors previously classified separately as meningeal solitary fibrous tumor and hemangiopericytoma [1]. It is rare, accounting for <1% of all primary central nervous system (CNS) tumors and most commonly affects adults [2]. Majority of these tumors are Dural-based.…”