Multi-institutional analysis of treatment modalities in basal ganglia and thalamic germinoma.

BACKGROUND: Central nervous system (CNS) germinomas are treatment-sensitive tumors with excellent survival outcomes. Current treatment strategies combine chemotherapy with radiotherapy (RT) in order to reduce the field and dose of RT. Germinomas originating in the basal ganglia/thalamus (BGTGs) have proven challenging to treat given their rarity and poorly defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have all been utilized; however, the best treatment strategy remains unclear. METHODS: Retrospective multi-institutional analysis has been conducted across 18 institutions in four countries. RESULTS: For 43 cases of nonmetastatic BGTGs, the 5- and 10-year event-free survivals (EFS) were 85.8% and 81.0%, respectively, while the 5- and 10-year overall survivals (OS) were 100% and 95.5%, respectively (one patient fatality from unrelated cause). Median RT doses were as follows: CSI: 2250 cGy/cGy(RBE) (1980-2400); WBI: 2340 cGy/cGy(RBE) (1800-3000); WVI: 2340 cGy/cGy(RBE) (1800-2550); focal: 3600 cGy (3060-5400). Thirty-eight patients (90.5%) received chemotherapy. There was no statistically significant difference in the EFS based on initial field extent (p = .84). Nevertheless, no relapses were reported in patients who received CSI or WBI. Chemotherapy alone had significantly inferior EFS compared to combined therapy (p = .0092), but patients were salvageable with RT. CONCLUSION: Patients with BGTGs have excellent outcomes and RT proved to be an integral component of the treatment plan. This group of patients should be included in future prospective clinical trials and the best RT field should be investigated further.

Brain biomarkers and neuropsychological outcomes of pediatric posterior fossa brain tumor survivors treated with surgical resection with or without adjuvant chemotherapy.

PURPOSE: Children with brain tumors experience cognitive late effects, often related to cranial radiation. We sought to determine differential effects of surgery and chemotherapy on brain structure and neuropsychological outcomes in children who did not receive cranial radiation therapy (CRT). METHODS: Twenty-eight children with a history of posterior fossa tumor (17 treated with surgery, 11 treated with surgery and chemotherapy) underwent neuroimaging and neuropsychological assessment a mean of 4.5 years (surgery group) to 9 years (surgery + chemotherapy group) posttreatment, along with 18 healthy sibling controls. Psychometric measures assessed IQ, language, executive functions, processing speed, memory, and social-emotional functioning. Group differences and correlations between diffusion tensor imaging findings and psychometric scores were examined. RESULTS: The z-score mapping demonstrated fractional anisotropy (FA) values were ≥2 standard deviations lower in white matter tracts, prefrontal cortex gray matter, hippocampus, thalamus, basal ganglia, and pons between patient groups, indicating microstructural damage associated with chemotherapy. Patients scored lower than controls on visuoconstructional reasoning and memory (P ≤ .02). Lower FA in the uncinate fasciculus (R = -0.82 to -0.91) and higher FA in the thalamus (R = 0.73-0.91) associated with higher IQ scores, and higher FA in the thalamus associated with higher scores on spatial working memory (R = 0.82). CONCLUSIONS: Posterior fossa brain tumor treatment with surgery and chemotherapy affects brain microstructure and neuropsychological functioning years into survivorship, with spatial processes the most vulnerable. Biomarkers indicating cellular changes in the thalamus, hippocampus, pons, prefrontal cortex, and white matter tracts associate with lower psychometric scores.

Brainstem primitive neuroectodermal tumors (bstPNET): results of treatment with intensive induction chemotherapy followed by consolidative chemotherapy with autologous hematopoietic cell rescue.

We have evaluated the response rate and survival utilizing intensified chemotherapy followed by myeloablative chemotherapy with autologous hematopoietic cell rescue (AuHCR) and adjuvant radiation therapy in six young children with newly diagnosed brainstem primitive neuroectodermal tumors (bstPNET). Following maximum surgical resection of the tumor, patients received high dose induction chemotherapy including vincristine, cisplatin, cyclophosphamide, and etoposide. Eligible patients received a single cycle of myeloablative chemotherapy followed by AuHCR. Two patients survive at least 32 months with stable disease. This approach provides an alternative for young patients with bstPNET who in prior reports have had a uniformly fatal prognosis.

Feasibility and response to induction chemotherapy intensified with high-dose methotrexate for young children with newly diagnosed high-risk disseminated medulloblastoma.

PURPOSE: To evaluate the feasibility of and response rate to an intensified induction chemotherapy regimen for young children with newly diagnosed high-risk or disseminated medulloblastomas. PATIENTS AND METHODS: From January 1997 to March 2003, 21 patients with high-risk or disseminated medulloblastoma were enrolled. After maximal surgical resection, patients were treated with five cycles of vincristine (0.05 mg/kg/wk x three doses per cycle for three cycles), cisplatin (3.5 mg/kg per cycle), etoposide (4 mg/kg/d x 2 days per cycle), cyclophosphamide (65 mg/kg/d x 2 days per cycle) with mesna, and methotrexate (400 mg/kg per cycle) with leucovorin rescue. Following induction chemotherapy, eligible patients underwent a single myeloablative chemotherapy cycle with autologous stem-cell rescue. RESULTS: Significant toxicities of this intensified regimen, including gastrointestinal and infectious toxicities, are described. Among the 21 patients enrolled, there were 17 complete responses (81%), two partial responses, one stable disease, and one progressive disease. The 3-year event-free survival and overall survival are 49% (95% CI, 27% to 72%) and 60% (95% CI, 36% to 84%), respectively. CONCLUSION: This intensified induction chemotherapy regimen is feasible and tolerable. With the majority of patients with disseminated medulloblastoma having M2 or M3 disease at diagnosis, the encouraging high response rate of this intensified induction regimen suggests that such an addition of methotrexate should be explored in future studies.