Successful treatment of leptomeningeal gliomatosis of pilomyxoid astrocytoma after failed frontline chemotherapy

Craniospinal irradiation with concomitant and adjuvant temozolomide--a feasibility assessment of toxicity in patients with glioblastoma with a PNET component

There is no standard treatment for glioblastoma with elements of PNET (GBM-PNET). Conventional treatment for glioblastoma is surgery followed by focal radiotherapy with concurrent temozolomide. Given the increased propensity for neuroaxial metastases seen with GBM-PNETs, craniospinal irradiation (CSI) with temozolomide (TMZ) could be a feasible treatment option but little is known regarding its toxicity. The clinical records of all patients treated at two UK neuro-oncology centres with concurrent CSI and TMZ were examined for details of surgery, radiotherapy, chemotherapy and toxicities related to the CSI-TMZ component of their treatment. Eight patients were treated with CSI-TMZ, the majority (6/8) for GBM-PNET. All patients completed radiotherapy to the craniospinal axis 35-40 Gy in 20-24 daily fractions with a focal boost to the tumour of 14-23.4 Gy in 8-13 daily fractions. Concurrent TMZ was administered at 75 mg/m(2) for seven of the cohort, with the other patient receiving 50 mg/m(2). The most commonly observed non-haematological toxicities were nausea and vomiting, with all patients experiencing at least grade 2 symptoms of either or both. All patients had at least grade 3 lymphopaenia. Two patients experience grade 4 neutropaenia and grade 3 thrombocytopaenia. Three of the eight patients required omission of TMZ for part of their chemoradiotherapy and 3/8 required hospital admission at some point during chemoradiotherapy. The addition of TMZ to CSI did not interrupt radiotherapy. Principal toxicities were neutropaenia, lymphopaenia, thrombocytopaenia, nausea and vomiting. Treatment with CSI-TMZ merits further investigation and may be suitable for patients with tumours at high-risk of metastatic spread throughout the CNS who have TMZ-sensitive pathologies.

Cystic pilomyxoid astrocytoma on suprasellar region in 7-year-old girl: Treatment and strategy

Pilomyxoid astrocytoma (PMA) is a recently described entity with similar features to pilocytic astrocytoma but with a rare occurrence. As a new diagnosis, no treatment guideline of PMA has been established; but generally, as for any low-grade gliomas, radical resection is performed if the location is favorable. In this report, we wished to share our experience treating the PMA. The authors presented a case of a 7-year-old girl with bitemporal hemianopia. From the history, the patient had a 4-month history of headache, following with nausea and projectile vomiting 1 week before hospital admission. Past history of seizure, weakness of left extremities, and decreased consciousness were reported. Computed tomography (CT) scanning showed acute obstructive hydrocephalus and an isohypodense mass at suprasellar region with the cystic component. We performed ventriculo-peritoneal-shunt to reduce the acute hydrocephalus, followed by craniotomy tumor removal 2 weeks later. The patient underwent radiotherapy and medical rehabilitation. Diagnosis of PMA was made on the basis of pathologic anatomy result, which showed a myxoid background with pseudorosette. Postoperative CT showed a residual tumor at right parasellar area without hydrocephalus. After the surgery, the treatment was followed with radiotherapy for 20 times within 2 months. Postradiation CT performed 1-year later showed a significant reduction of the tumor mass. There were no new postoperative deficits. The patient had improvement of the visual field and motor strength. The authors reported a case of a 7-year-old girl with PMA. Surgical resection combined with radiotherapy was performed to control the growth of PMA. More observation and further studies are required to refine the treatment methods.

Pilomyxoid Astrocytoma (PMA) Shows Significant Differences in Gene Expression vs. Pilocytic Astrocytoma (PA) and Variable Tendency Toward Maturation to PA

Pilomyxoid astrocytomas (PMAs) manifest a more aggressive clinical course than pilocytic astrocytomas (PAs). Development of effective therapies demands a better biological understanding of PMA. We first conducted gene expression microarray analysis of 9 PMA and 13 PA from infra- and supratentorial sites. Unsupervised hierarchical clustering analysis demonstrated that tumors are grouped according to anatomic site, not diagnosis. Gene expression profiles were then contrasted between eight PMAs and six PAs, all supratentorial/hypothalamic/chiasmal. Clinical outcome of PMAs varied, with four out of four patients with diencephalic syndrome succumbing to disease, one of whom showed bulky metastatic leptomeningeal spread at autopsy, with bimodal maturation to PA in some areas and de-differentiation to glioblastoma in others. A surviving child has undergone multiple surgical debulking, with progressive maturation to PA over time. Ontology-enrichment analysis identified overexpression in PMAs of extracellular matrix and mitosis-related genes. Genes overexpressed in PMA vs. PA, ranked according to fold-change, included developmental genes H19, DACT2, extracellular matrix collagens (COL2A1; COL1A1) and IGF2BP3 (IMP3), the latter previously identified as an adverse prognostic factor in PMA and PA.

Pilomyxoid astrocytoma with high proliferation index

Pilomyxoid astrocytomas is an uncommon aggressive piloid neoplasm, closely related to pilocytic astrocytomas and typically presents in the very young but can occur in older children and rarely in adults. A 12-years-old male presented with focal seizures, headache and vomiting of 10 days duration. Computed tomogram showed a hypo- to hyperdense and peripherally enhancing, solid-cystic lesion in the left temporal lobe. Histopathological examination revealed a characteristic tumor composed of bipolar cells arranged in dyscohesive sheets, angiocentric pattern in a loose myxoid background, with brisk mitotic activity and foci of necrosis. No Rosenthal fibers or eosinophilic granular bodies were seen. The tumor cells showed strong GFAP and scattered p53 positivity, but were negative for EMA. Ki-67 positivity ranged from 30 to 40%, highest reported till date. The patient was treated with radiotherapy and concurrent temozolamide and the tumor recurred after two years.