AN ASTROBLASTOMA MIMICKING A CAVERNOUS MALFORMATION

Possible association between minor head injury and intratumoral hemorrhage: A metastatic brain tumor from thyroid carcinoma

A 78-year-old woman presented after a fall and injury in the left forehead. She had undergone surgery for papillary thyroid carcinoma 14 years prior and breast carcinoma 7 years prior. The patient had exhibited uneventful postoperative courses without relapse or metastasis. Anticoagulants or antiplatelet agents were not prescribed her. At presentation, the patient exhibited no focal neurological deficits. Computed tomography revealed a 19 × 20 mm hemorrhagic lesion in the right temporal lobe. On cerebral magnetic resonance imaging, the center of the lesion exhibited inhomogeneous intensity on both T1- and T2-weighted sequences with heterogeneous enhancement. In contrast, the perilesional hemorrhagic regions, appearing hyperintense on both T1- and T2-weighted sequences, showed temporary regression followed by marked enlargement over the subsequent 123 days. The patient underwent total tumor resection. The microscopic findings of the resected specimens were consistent with papillary thyroid carcinoma. Minor head injuries may trigger intratumoral hemorrhage in metastatic brain tumors. Metastasis should be assumed when patients with a history of thyroid carcinoma present with a solitary parenchymal lesion with the appearance of cerebral cavernous malformation, even if they have been disease free for a long period.

Neuroimaging of astroblastomas: A case series and systematic review

BACKGROUND AND PURPOSE

Astroblastoma is a rare type of glial tumor, histologically classified into two types with different prognoses: high and low grade. We aimed to investigate the CT and MRI findings of astroblastomas by collecting studies with analyzable neuroimaging data and extracting the imaging features useful for tumor grading.

METHODS

We searched for reports of pathologically proven astroblastomas with analyzable neuroimaging data using PubMed, Scopus, and Embase. Sixty-five studies with 71 patients with astroblastomas met the criteria for a systematic review. We added eight patients from our hospital, resulting in a final study cohort of 79 patients. The proportion of high-grade tumors was compared in groups based on the morphology (typical and atypical) using Fisher's exact test.

RESULTS

High- and low-grade tumors were 35/71 (49.3%) and 36/71 (50.7%), respectively. There was a significant difference in the proportion of high-grade tumors based on the tumor morphology (typical morphology: high-grade = 33/58 [56.9%] vs. atypical morphology, 2/13 [15.4%], p = .012). The reviews of neuroimaging findings were performed using the images included in each article. The articles had missing data due to the heterogeneity of the collected studies.

CONCLUSIONS

Detailed neuroimaging features were clarified, including tumor location, margin status, morphology, CT attenuation, MRI signal intensity, and contrast enhancement pattern. The classification of tumor morphology may help predict the tumor's histological grade, contributing to clinical care and future oncologic research.

High-Grade Intraventricular Astroblastoma in a Young Adult: A Rare and Controversial Tumor to Manage

Astroblastoma is a rare primary central nervous system tumor of controversial site of origin. They account for 0.45-2.8% of all primary neuroepithelial central nervous system. It has been reported in paediatric age group with bimodal age distribution affecting more females with male to female ratio being 1:11. Astroblastomas are controversial and challenging tumors in terms of diagnosis and therapeutics. Since it carries an unpredictable disease course it needs a regular follow up even for low grade tumor. Authors have tried various schedules of post op radiotherapy after maximum safe resection. Various chemotherapeutic drugs combination have also been tried without much success. We here report a 35 years old female patient who was diagnosed with high grade astroblastoma referred for post-operative radiotherapy after gross total resection. Since it is extremely rare tumor, its treatment still not well defined and also makes it difficult conduct studies to examine tumor characteristics.

Astroblastoma in a Young Female Patient: A Case Report and Literature Review of Clinicopathological, Radiological and Prognostic Characteristics and Current Treatment Strategies

Astroblastoma is an uncommon glial tumor with predominant manifestation in the young age. Herein, we report a case of 18-year-old astroblastoma female patient who presented with history of two months headache. Magnetic resonance imaging (MRI) of the brain demonstrated well circumscribed, intra-axial abnormal signal intensity lesion (size=5×4 cm²) in the right parieto-occipital region of the brain. The patient underwent complete surgical resection of the gross tumor, as confirmed by an early post-surgical MRI (i.e., within 24 hours of surgery). Histopathological examination revealed neoplastic lesion exhibiting perivascular pseudo-rosettes with centrally hyalinized blood vessel and focal nuclear pleomorphism. Immunohistochemistry staining illustrated reactivity for glial fibrillary acidic protein and integrase interactor 1 (INI-1). These features rendered the diagnosis of astroblastoma. A comprehensive review of the current literature to summarize the clinicopathological and radiological characteristics, prognostic factors and current treatment strategies of astroblastomas is also presented. Our study would expand the pool of this uncommon tumor towards its better understanding and optimal treatment.

Patterns of care and survival outcomes in patients with astroblastoma: an individual patient data analysis of 152 cases

BACKGROUND

Astroblastoma (AB) is a rare tumor with significant dilemma regarding diagnostic criteria, behavior, and optimum treatment.

MATERIALS AND METHODS

We searched PubMed, Google Search, and Cochrane Library for eligible studies with the following search words: astroblastoma, high-grade astroblastoma, and anaplastic astroblastoma till July 1, 2016, published in English language and collected data regarding age, sex, site of disease, pathological grade, treatment received, and survival.

RESULTS

Data of 152 patients were retrieved from 63 publications. Median age was 16 years (range 0-71). Females were affected twice more frequently than male (70.3 vs. 29.7%). Tumors were most commonly located in the frontal (39%) followed by parietal lobe (26.7%). Fifty-two and 25% of the patients had headache and seizure at presentation, 76.3% of the patients underwent a gross total resection, 41 out of 89 had a high-grade tumor, and 56 patients received adjuvant radiation with a median dose of 54 Gy (range 20-72). Adjuvant chemotherapy was used in 23 patients. Temozolomide was the most common drug used in 30% of the patients. A combination of cisplatin, etoposide with vincristine, or ifosfamide was used in 17%. Median follow-up duration was 37 months (range 1-238). Median progression-free survival and OS were 36 and 184 months, respectively. Patients with a higher-grade tumor had significantly worse OS with HR 5.260 and p = 0.001. Forty patients experienced local progression. Sixty-five percent patients underwent surgery while 50% underwent radiation as salvage.

CONCLUSION

AB has two distinct grades with higher-grade tumors having significantly poor survival. Maximal safe surgery followed by adjuvant radiation and temozolomide should be advocated for these tumors.

A Pediatric Tumor Found Frequently in the Adult Population: A Case of Anaplastic Astroblastoma in an Elderly Patient and Review of the Literature

Astroblastomas are rare, potentially curable primary brain tumors which can be difficult to diagnose. We present the case of astroblastoma in a 73-year-old male, an atypical age for this tumor, more classically found in pediatric and young adult populations. Through our case and review of the literature, we note that this tumor is frequently reported in adult populations and the presentation of this tumor in the elderly is well described. This tumor is an important consideration in the differential diagnosis when managing both pediatric and adult patients of any age who present with the imaging findings characteristic of this rare tumor.

Neuroradiologic characteristics of astroblastoma and systematic review of the literature: 2 new cases and 125 cases reported in 59 publications

BACKGROUND

Astroblastoma is a rare tumor of uncertain origin most commonly presenting in the cerebrum of children and young adults. The literature contains only case reports and small series regarding its radiologic features. This systematic review is the largest study of imaging findings of astroblastoma to date and serves to identify features that might differentiate it from other neoplasms.

OBJECTIVE

This study describes the imaging features of astroblastoma based on a systematic review of the literature and two new cases.

MATERIALS AND METHODS

We conducted a PubMed and Google Scholar database search that identified 59 publications containing 125 cases of pathology-confirmed astroblastoma, and we also added two new cases from our own institution. Data collected include patient age, gender, tumor location, morphology, calcifications and calvarial changes. We recorded findings on CT, MRI, diffusion-weighted imaging (DWI), MR spectroscopy, positron emission tomography (PET) and catheter angiography.

RESULTS

Age at diagnosis ranged 0-70 years (mean 18 years; median 14 years). Female-to-male ratio was 8:1. Of 127 cases, 66 reported CT, 78 reported MRI and 47 reported both findings. Not all authors reported all features, but the tumor features reported included supratentorial in 96% (122/127), superficial in 72% (48/67), well-demarcated in 96% (79/82), mixed cystic-solid in 93% (79/85), and enhancing in 99% (78/79). On CT, 84% (26/31) of astroblastomas were hyperattenuated, 73% (27/37) had calcifications and 7 cases reported adjacent calvarial erosion. Astroblastomas were hypointense on T1-W in 58% (26/45) and on T2-W in 50% (23/46) of MRI sequences. Peritumoral edema was present in 80% (40/50) of cases but was typically described as slight. Six cases included DWI findings, with 100% showing restricted diffusion. On MR spectroscopy, 100% (5/5) showed nonspecific tumor spectra with elevated choline and decreased N-acetylaspartate (NAA). PET revealed nonspecific reduced uptake of [F-18] 2-fluoro-2-deoxyglucose ((18)F-FDG) and increased uptake of [11C]-Methionine in 100% (3/3) of cases. Catheter angiography findings (n=12) were variable, including hypervascularity in 67%, arteriovenous shunting in 33% and avascular areas in 25%.

CONCLUSION

Astroblastomas occur most often in adolescent girls. Imaging often shows a supratentorial, superficial, well-defined, cystic-solid enhancing mass. On CT, most are hyperattenuated, have calcifications, and may remodel adjacent bone if superficial. MRI characteristically reveals a hypointense mass on T1-W and T2-W sequences with restricted diffusion. MR spectroscopy, PET and catheter angiography findings are nonspecific.

Hemorrhage in astroblastoma: An unusual manifestation of an extremely rare entity

Astroblastoma is a rare tumor of glial origin with characteristics of both astrocytoma and ependymoma. It is usually seen in children and young adults, and is peripherally located, well circumscribed, of solid-cystic composition and with heterogeneous contrast enhancement. Histopathology reveals perivascular pseudorosette formation and thick hyalinised vessels. Hemorrhage in astroblastoma is unusual and rarely described in literature. We report two patients with astroblastoma who presented with hemorrhage and discuss the natural history, radiological findings, pathophysiology of hemorrhage and histopathological characteristics. We emphasize the importance of early suspicion in peripherally located lesions with bleeding.

High-grade astroblastoma in a child: Report of one case and review of literature

Background:

Astroblastoma is a rare glial neoplastic lesion that affects children and adolescents; its histogenesis remains uncertain. It is considered to account for 0.5% of all glial neoplasms, and two different subtypes have been defined based upon histologic characteristics.

Case Description:

We present the case of a 9-year-old girl who presented with headache, motor symptoms, and seizures few days before she was admitted to our institution. Computed tomography (CT) and magnetic resonance imaging (MRI) scans showed an intra-axial heterogeneous frontoparietal lesion with a striking “bubbly” appearance in MRI T2-weighted sequences and features of intracranial hypertension. Gross total resection of the tumor was achieved and the histopathologic diagnosis revealed high-grade astroblastoma. We reviewed the current published cases of astroblastoma to highlight the demographic, clinical, radiologic, and pathologic data.

Conclusion:

Astroblastomas are a distinct clinicopathologic entity, with well-described radiologic, pathologic, and cytogenetic features. Its recurrence is high and efforts must be made to elucidate the role and usefulness of radiotherapy and chemotherapy in these tumors.

Anaplastic astroblastoma presenting as massive, sudden-onset, intraparenchymal hemorrhage

Astroblastoma is a rare primary glial tumor of children and young adults, typically located in the cerebral hemispheres and presenting as a well-circumscribed, nodular, often cystic enhancing mass. The existence of astroblastoma as a distinct clinicopathologic entity has long been debated but is recognized in the 2007 WHO classification of CNS tumors. The grading of these tumors remains unsettled. Currently, no grade has been established and there are no clearly defined diagnostic criteria for low- or high-grade tumors. Astroblastomas in general are thought to have a favorable outcome with low rates of recurrence following gross total resection. We report a case of astroblastoma with 'high-grade/anaplastic' histology in a 12-year-old, previously healthy girl. The patient experienced severe, sudden-onset headache, and quickly became comatose. Head CT showed a massive intraparenchymal hemorrhage in the right frontal lobe with surrounding edema. She underwent emergent posterior frontal craniotomy for decompression and hematoma evacuation. Pathologic examination revealed a sharply demarcated hemorrhagic heterogeneous glial tumor with focal papillary architecture, densely hyalinized blood vessels, and intensely GFAP-positive perivascular cells. The tumor showed unequivocal high-grade features including an elevated proliferative index. The diagnosis of anaplastic astroblastoma was rendered. The patient expired on postoperative day 30. This case illustrates the potential poor outcome of high-grade astroblastoma and highlights the morphologic heterogeneity of this rare neoplasm.

Intraventricular astroblastoma. Case report

Astroblastoma is a rare primary brain neoplasm that accounts for 0.45-2.8% of brain gliomas. Intraventricular localization is extremely rare. The authors report a case of well-differentiated completely intraventricular astroblastoma in a 6-year-old girl and review the relevant literature. Their patient presented with a 5-week history of progressive nausea and vomiting. Magnetic resonance (MR) imaging revealed a large, well-demarcated, solid-cystic mass in the left temporooccipital ventricular horn. Macroscopic radical resection of the tumor was performed via the superior temporal sulcus. The postoperative course was uneventful and no adjuvant therapy was administered after surgery. No recurrence was detected at 9-months follow-up. Gross-total resection has the greatest impact on patient survival. In differentiated tumors, recurrence is usually local, and adjuvant therapy is recommended after repeated resection for the treatment of recurrence. In patients harboring anaplastic astroblastoma, gross-total resection and adjuvant therapy after the initial surgery seems to be the best choice. It is important to distinguish astroblastoma from ependymoma in clinical practice because of the differences in therapeutic approaches.