Pleomorphic xanthoastrocytoma with anaplastic features: A rare case report and review of literature with reference to current management

Proton Beam Therapy for a Rare Anaplastic Pleomorphic Xanthoastrocytoma: Case Report and Literature Review

Anaplastic pleomorphic xanthoastrocytoma (PXA) is a rare, aggressive WHO grade III tumor that primarily affects children and young adults. Despite surgery being the primary treatment, achieving complete tumor removal is often difficult due to its infiltrative nature, necessitating additional therapies like proton beam therapy (PBT). PBT, known for its precision in targeting tumors while minimizing damage to surrounding healthy tissue, has shown promise in treating malignant gliomas. We present the case of a 9-year-old girl with anaplastic PXA treated with PBT following incomplete surgical resection. A total dose of 60 Gy (RBE) in 15 fractions was administered, leading to significant tumor reduction, no progression, and improved local control at the 1-year follow-up, with no observed adverse effects. Based on short-term follow-up results, our study highlights the potential of PBT in managing anaplastic PXA, demonstrating favorable local outcomes and a low incidence of radiation-induced complications. While long-term follow-up and evaluation are necessary to further support these findings, this case represents only the second reported instance of anaplastic PXA treated with PBT, contributing to the growing body of evidence supporting its efficacy in this rare tumor type.

Drug-resistant schizophrenia-like psychosis associated with temporal non-anaplastic pleomorphic xanthoastrocytoma: unusual revealing symptom of a rare pathology

Introduction and importance

Pleomorphic xanthoastrocytoma (PXA) was first described by Kepes et al. in 1979. Fewer than 200 cases have been reported in the literature. It generally involves the temporoparietal lobe. PXA has a favorable prognosis. The most reported clinical manifestation is epileptic seizures. Revealing psychiatric symptoms have an incidence varying from 50 to 78%. The most common symptoms encountered are anxiety disorders, depression, schizophrenia-like psychosis, cognitive dysfunction or even anorexia nervosa.

Case presentation

Here, the authors report a new case of non-anaplastic pleomorphic xanthoastrocytoma revealed by a drug-resistant schizophrenia-like psychosis in a 26-year-old male patient known with epileptic seizures in whom these two pathologies were intertwined and had been evolving for 5 years. The postoperative course was uneventful, and positive symptoms of schizophrenia were relatively stabilized at discharge.

Clinical discussion

Given the superficial hemispheric location of PXA, the most common clinical presentation is seizures. Psychiatric symptoms revealing brain tumors have an incidence varying from 50 to 78%. Most of these symptoms concern frontal and limbal tumors. In their case, the tumor was located in the right temporal lobe. Surgery was performed and postoperative course was uneventful even though there are conflicting reports regarding the importance of the surgical excision quality.

Conclusion

PXA remains a rare and benign primary CNS tumor. Psychiatric disorders represent a rare revealing mode of this pathology, which must lead to neuroimaging in any patient carrying this type of symptoms.

Successful Treatment with Dabrafenib/Trametinib of a Malignantly Transformed and Metastasized BRAF V600E Mutant Pleiomorphic Xanthoastrocytoma: A Case Report and Review of the Literature

Introduction

Pleiomorphic xanthoastrocytoma (PXA) is considered a low-grade glioma with a favorable prognosis following surgical resection. We present a case report of a BRAFV600E mutant malignantly transformed and disseminated PXA that was successfully treated with BRAF-/MEK-targeted therapy (dabrafenib/trametinib).

Case Presentation

At the age of 16 years, our patient underwent an initial subtotal resection of a right occipital PXA. Six months later, a reintervention for an asymptomatic tumor recurrence was performed and complete resection was achieved. The patient has been followed up by MRI for 14 years without arguments for recurrence but was lost to follow-up thereafter. At 38 years of age, he presented with a symptomatic local recurrence with extra-cerebral soft tissue extension, for which a third surgical resection was performed. Anatomopathological examination reported a grade 3 anaplastic PXA (aPXA); molecular analysis detected a BRAFV600E mutation. Three months later, before the initiation of radiotherapy, a local tumor recurrence was diagnosed, for which he underwent a fourth surgical resection. Radiotherapy was performed following the surgical debulking. One month after completion of radiotherapy, disease progression was documented including multiple sites of extracranial metastases (skeletal, lung, cervical lymph node, and subcutaneous metastases). Systemic treatment with a combination of BRAF-/MEK-inhibitors (dabrafenib/trametinib) was initiated and resulted in a rapid and deep tumor response (partial response according to RECISTv1.1) and absence of BRAFV600E mutant ctDNA in plasma at 6 weeks after treatment initiation. A near-complete metabolic remission was documented on [18F]FDG-PET/CT 3 months after starting systemic therapy.

Conclusion

We present a rare case of malignant transformation and systemic dissemination of a BRAFV600E mutant PXA, occurring 20 years after the initial diagnosis. This case highlights the importance of long-term follow-up of patients diagnosed with these rare central nervous system tumors that initially are considered benign and also illustrates that BRAF/MEK inhibition can be an effective therapy for BRAFV600E mutated PXA, underscoring the importance of performing molecular genetic profiling of these tumors.

A rare case of cerebellar anaplastic pleomorphic xanthoastrocytoma

Pleomorphic xanthoastrocytoma (PXA) is a low-grade glioma comprising 1% of all astrocytomas with an extremely rare anaplastic counterpart usually found in young adults. These tumors are most often cerebral in origin and their presentation in the elderly signifies poor prognosis. As these tumors are an important differential of glioblastoma, diagnosing them accurately is essential for management. We present a 68-year-male with positive cerebellar signs and clinico-radiological impression of cerebellar metastatic deposits, subsequently diagnosed as cerebellar PXA with anaplastic features. The case in discussion is unique in its age, site, and grade of presentation, with key histological features rebuking the clinical and radiological diagnosis of metastasis. The rarity and ambiguous management protocol of these tumors make their documentation an important addition to the existing literature with emphasis on possibility of late presentation and at sites other than the cerebrum.

Clinical features and surgical outcomes of high grade pleomorphic xanthoastrocytomas: a single-center experience with a systematic review

Purpose

High grade pleomorphic xanthoastrocytomas (HGPXAs) are very rare and their management and prognostic outcomes remain unclear. To better understand the disease, we aimed to evaluate the risk factors for progression-free survival (PFS) and overall survival (OS), and propose a treatment protocol based on cases from our institute and cases from the literature.

Methods

The authors reviewed the clinical data of 26 patients with HGPXAs who underwent surgical treatment in Department of Neurosurgery of Beijing Tiantan Hospital between August 2014 and September 2021. We also searched the PubMed database using the keywords "anaplastic" combined with "pleomorphic xanthoastrocytoma(s)" between January 1997 and October 2022. Risk factors for PFS and OS were evaluated in the pooled cases.

Results

The authors' cohort included 11 males and 15 females with a mean age of 36.7 ± 20.3 years (range: 5.5-71 years). Gross-total resection (GTR) and non-GTR were achieved in 17 (65.4%) and 9 (34.6%) patients, respectively. Radiotherapy and chemotherapy were administered to 22 and 20 patients, respectively. After a mean follow-up of 20.5 ± 21.2 months (range: 0.5-78.1 months), 7 patients suffered tumor recurrence and 6 patients died with a mean OS time of 19.4 ± 10.8 months (range: 8-36 months). In the literature between January 1997 and October 2022, 56 cases of HGPXAs were identified in 29 males and 27 females with a mean age of 29.6 ± 19.6 years (range; 4-74 years). Among them, 24 (44.4%) patients achieved GTR. Radiotherapy and chemotherapy was administered to 31 (62%) patients and 23 (46%) patients, respectively. After a median follow-up of 31.4 ± 35.3 months (range: 0.75-144 months), the mortality and recurrence rates were 32.5% (13/40) and 70% (28/40), respectively. Multivariate Cox regression model demonstrated that non-GTR (HR 0.380, 95% CI 0.174-0.831, p=0.015), age≥30 (HR 2.620, 95% CI 1.183-5.804, p=0.018), no RT (HR 0.334,95% CI 0.150-0.744, p=0.007) and no CT (HR 0.422, 95% CI 0.184-0.967, p=0.042) were negative prognostic factors for PFS. Non-GTR (HR 0.126, 95% CI 0.037-0.422, p=0.001), secondary HGPXAs (HR 7.567, 95% CI 2.221-25.781, p=0.001), age≥30 (HR 3.568, 95% CI 1.190-10.694, p=0.023) and no RT (HR 0.223,95% CI 0.073-0.681, p=0.008) were risk factors for OS.

Conclusion

High grade pleomorphic xanthoastrocytomas are very rare brain tumors. Children and younger adults have better clinical outcome than elderly patients. Secondary HGPXAs had worse OS than primary HGPXAs. Complete surgical excision plus RT and CT is recommended for this entity. The frequency of BRAF mutations in HGPXAs is 47.5% (19/40) in this study, however, we do not find the connections between BRAF mutations and clinical outcomes. Future studies with larger cohorts are necessary to verify our findings.

Anaplastic Pleomorphic Xanthoastrocytoma: A Rare Variant of Astrocytoma

Pleomorphic xanthoastrocytoma (PXA) is a rare glioma that affects 1% of astrocytic tumors. It most commonly affects children and teenagers. PXA cases with an anaplastic histopathological subtype have been reported in recent years. It was recently classified as a separate subtype in the 2016 World Health Organization (WHO) classification of central nervous system (CNS) tumors. A 48-year-old healthy gentleman presented with progressive right upper limb weakness. CT and MRI of the brain were done, which showed an intra-axial supratentorial tumor. A diagnosis of high-grade glioma was initially made based on its imaging features. The histopathological study came back as anaplastic pleomorphic xanthoastrocytoma. After a discussion with the neurosurgical and oncology teams, a decision was made to treat the patient with radiotherapy. In this case report, we describe a rare case of PXA with anaplastic characteristics.

Differences in treatment patterns and overall survival between grade II and anaplastic pleomorphic xanthoastrocytomas

INTRODUCTION

Pleomorphic xanthoastrocytomas (PXAs) are classified as a grade II neoplasm, typically occur in children, and have favorable prognoses. However, their anaplastic counterparts remain poorly understood and vaguely characterized. In the present study, a large cohort of grade II PXA patients were compared with primary anaplastic PXA (APXA) patients to characterize patterns in treatment and survival.

METHODS

Data were collected from the National Cancer Institute's SEER database. Univariate and multivariate Cox regressions were used to evaluate the prognostic impact of demographic, tumor, and treatment-related covariates. Propensity score matching was used to balance baseline characteristics. Kaplan-Meier curves were used to estimate survival.

RESULTS

A total of 346 grade II PXA and 62 APXA patients were identified in the SEER database between 2000 and 2016. Kaplan-Meier analysis revealed substantially inferior survival for APXA patients compared to grade II PXA patients (median survival: 51 months vs. not reached) (p < 0.0001). After controlling across available covariates, increased age at diagnosis was identified as a negative predictor of survival for both grade II and APXA patients. In multivariate and propensity-matched analyses, extent of resection was not associated with improved outcomes in either cohort.

CONCLUSIONS

Using a large national database, we identified the largest published cohort of APXA patients to date and compared them with their grade II counterparts to identify patterns in treatment and survival. Upon multivariate analysis, we found increased age at diagnosis was inversely associated with survival in both grade II and APXA patients. Receipt of chemoradiotherapy or complete surgical resection was not associated with improved outcomes in the APXA cohort.

Long-term Efficacy of Single-agent Vemurafenib for Pleomorphic Xanthoastrocytoma

Pleomorphic xanthoastrocytoma is a malignant brain tumor that has a good prognosis with complete resection but does not respond well to chemotherapy if there is residual tumor. BRAF V600E mutations are common in pleomorphic xanthoastrocytomas and provide an additional means for treatment when excision is not possible. Monotherapy with the BRAF V600E inhibitor vemurafenib has only been reported in a small number of cases and mostly in adults. We present the case of a 16-year-old male who responded to vemurafenib monotherapy initially and had an additional response to vemurafenib following progression after a brief time off the medication.

Demography, Pattern of Care, and Survival in Patients with Xanthoastrocytoma: A Systematic Review and Individual Patient Data Analysis of 325 Cases

Objectives Xanthoastrocytoma (XA) is a low-grade glial tumor seen in young adults and there is lack of robust data on treatment of this rare tumor. In this systematic review and individual patient's data analysis, we aimed to look into the demography, pattern of care, survival outcomes, and prognostic factors in patients with both Grade II and III XA. Methods A comprehensive search was conducted with the Medical Subject Heading terms: "Xanthoastrocytoma; Pleomorphic Xanthoastrocytoma; Anaplastic Xanthoastrocytoma; Xanthoastrocytoma AND treatment; and Anaplastic Xanthoastrocytoma AND survival" to find all possible publications. Results A total of 325 individual patients from a total of 138 publications pertaining to XA were retrieved. Median age of the entire cohort was 19 years. About 56.1% of the patients underwent a gross total resection (GTR) and 31.4% underwent a subtotal resection. Nearly, 76.6% of the patients had a Grade II tumor and adjuvant radiation was delivered in 27.4% of the patients. Estimated 2- and 5-year progression-free survival (PFS) were 68.5 and 51.2%, respectively. Age, grade, and extent of surgery were significant factors affecting PFS. Estimated 2- and 5-year overall survival (OS) was 88.8 and 78%, respectively. The median OS for Grade II and Grade III tumors were 209 and 49 months, respectively. Age and extent of surgery were significant factors affecting OS. Conclusion XA is a disease of young adults with favorable prognosis. Younger patients (<20 years), patients who undergo a GTR, and patients with a lower grade tumor have a better treatment outcome.

Anaplastic Pleomorphic Xanthoastrocytoma Presenting with Musical Hallucination

Musical hallucinations are a relatively rare form of auditory hallucination characterized by hearing of music in the absence of any external stimuli. This phenomenon has been linked to both psychiatric and structural lesions. We present the case of a previously healthy young male whose presentation with musical hallucinations led to the diagnosis of a rare tumour, anaplastic pleomorphic xanthoastrocytoma.

Retinal anaplastic pleomorphic xanthoastrocytoma unassociated with phakomatosis

Purpose

To present a rare anaplastic form of retinal pleomorphic xanthoastrocytoma (PXA) unassociated with phakomatosis.

Methods

A 9-year-old girl, presented with a rapidly growing unilateral intraocular white mass unresponsive to intra-arterial chemotherapy, underwent enucleation with the clinical suspicion of retinoblastoma versus malignant astrocytoma.

Results

Histopathology revealed pleomorphic cells with rosenthal fibers, mitosis, and necrosis. Immunohistochemistry confirmed the diagnosis of anaplastic pleomorphic xanthoastrocytoma (aPXA). The patient had no signs of phakomatosis.

Conclusion

Retinal PXA may occur in patients without phakomatosis and rarely progress toward malignant transformation.

Clinico-Histomorphological and Immunohistochemical Profile of Anaplastic Pleomorphic Xanthoastrocytoma: Report of Five Cases and Review of Literature

Background: Pleomorphic xanthoastrocytoma is a rare tumour of children and young adults, particularly for those with features of anaplasia. Materials and Methods : This retrospective study comprises five cases of anaplastic pleomorphic xanthoastrocytomas diagnosed over a period of 4 years in a tertiary care institute. A detailed clinicopathological and immunohistochemical profile of the tumours were noted from the hospital database. Results: Five cases of anaplastic pleomorphic xanthoastrocytomas were evaluated for their clinicoradiological, histomorphological as well as immunohistochemical findings, which included 3 females and 2 males, with age range of 11-40 years and a mean age at presentation of 22 years. Histologically a solid cystic biphasic tumour with moderate to high cellularity, spindled pleomorphic astrocytes, hyperchromatic nuclei showing moderate to marked atypia, intranuclear inclusions, ≥5 mitoses per 10 high power fields, with evidence of necrosis and atypical mitoses was noted. One of the cases showed transformation into glioblastoma with evidence of spinal metastasis on follow-up. The tumours expressed both glial as well as neuronal markers with expression of CD34 with increased Ki 67 ranging between 5-20%. Conclusion: It was concluded that PXA, a low-grade glioneuronal tumour, can show odd site presentation, marked pleomorphism, increased mitosis, atypical mitoses and increased Ki 67 when associated with features of anaplasia. An appropriate panel of immunohistochemical markers in conjunction with a detailed evaluation of histomorphological features and clinicoradiological information are useful for its diagnosis.

MR Imaging Features of Anaplastic Pleomorphic Xanthoastrocytoma Mimicking High-Grade Astrocytoma

BACKGROUND AND PURPOSE

Anaplastic pleomorphic xanthoastrocytoma, which has been recently defined as a distinct entity in the 2016 World Health Organization classification, may exhibit aggressive clinical behavior and relatively worse prognosis than pleomorphic xanthoastrocytoma. This study aimed to investigate whether there were any differences in MR imaging characteristics between these 2 tumors.

MATERIALS AND METHODS

This retrospective study included 9 patients with anaplastic pleomorphic xanthoastrocytoma and 10 patients with pleomorphic xanthoastrocytoma who underwent MR imaging before an operation. DWI was performed in 17 patients (8 with anaplastic pleomorphic xanthoastrocytoma, 9 with pleomorphic xanthoastrocytoma); and DSC-PWI, in 9 patients (5 with anaplastic pleomorphic xanthoastrocytoma, 4 with pleomorphic xanthoastrocytoma). Demographics, conventional imaging characteristics (location, size, cystic degeneration, enhancement, peritumoral edema, and leptomeningeal contact), minimum relative ADC ratio, and maximum relative CBV ratio were evaluated between the anaplastic pleomorphic xanthoastrocytoma and pleomorphic xanthoastrocytoma groups.

RESULTS

Anaplastic pleomorphic xanthoastrocytoma was more likely to demonstrate high-grade features than pleomorphic xanthoastrocytoma, including greater maximum tumor diameter (4.7 ± 0.6 cm versus 3.1 ± 1.1 cm, P = .001), more frequent heterogeneous contrast enhancement of solid portions (88.9% versus 20.0%, P = .01), more obvious peritumoral edema (2.3 ± 0.9 cm versus 1.0 ± 0.9 cm, P = .008), lower minimum relative ADC on DWI (1.0 ± 0.2 versus 1.5 ± 0.4, P = .008), and higher maximum relative CBV on DSC-PWI (2.6 ± 0.8 versus 1.6 ± 0.2, P = .036).

CONCLUSIONS

Anaplastic pleomorphic xanthoastrocytomas often have more aggressive MR imaging features mimicking high-grade astrocytomas than pleomorphic xanthoastrocytomas. DWI and DSC-PWI might be useful in the characterization and differentiation of anaplastic pleomorphic xanthoastrocytoma and pleomorphic xanthoastrocytoma.