Distinct patterns of copy number alterations may predict poor outcome in central nervous system germ cell tumors.

We have previously reported that 12p gain may predict the presence of malignant components and poor prognosis for CNS germ cell tumor (GCT). Recently, 3p25.3 gain was identified as an independent predictor of poor prognosis for testicular GCT. Eighty-one CNS GCTs were analyzed. Copy number was calculated using methylation arrays. Five cases (6.2%) showed 3p25.3 gain, but only among the 40 non-germinomatous GCTs (NGGCTs) (5/40, 12.5%; p = 0.03). Among NGGCTs, those with a yolk sac tumor component showed a significantly higher frequency of 3p25.3 gain (18.2%) than those without (1.5%; p = 0.048). NGGCTs with gain showed significantly shorter progression-free survival (PFS) than those without (p = 0.047). The 3p25.3 gain and 12p gain were independent from each other. The combination of 3p25.3 gain and/or 12p gain was more frequent among NGGCTs with malignant components (69%) than among those without (29%; p = 0.02). Germinomas containing a higher number of copy number alterations showed shorter PFS than those with fewer (p = 0.03). Taken together, a finding of 3p25.3 gain may be a copy number alteration specific to NGGCTs and in combination with 12p gain could serve as a marker of negative prognosis or treatment resistance. Germinoma with frequent chromosomal instability may constitute an unfavorable subgroup.

Long-term effectiveness of Gliadel implant for malignant glioma and prognostic factors for survival: 3-year results of a postmarketing surveillance in Japan.

BACKGROUND: Adjuvant treatment with Gliadel wafers may prolong overall survival (OS) for malignant glioma patients without increasing toxicity. In Japan, the long-term OS of these patients treated with Gliadel 7.7 mg implants has not been studied. We evaluated OS and prognostic factors that might affect OS in Japanese patients with malignant glioma who received the Gliadel 7.7 mg implant. METHODS: This observational, long-term, postmarketing surveillance was an extension of a previous surveillance. Data were collected through case report forms at 2 and 3 years after Gliadel implant. Up to 8 Gliadel wafers (61.6 mg of carmustine) were placed over the tumor resection site. Primary endpoints were OS and prognostic factors that may influence OS. RESULTS: Among the 506 patients analyzed, 62.6% had newly diagnosed disease, and 37.4% had recurrent disease; 79.1% had glioblastoma histological type and 79.6% had World Health Organization Grade IV disease. Patients received a median of 8 wafers. The median OS was 18.0 months; OS rates were 39.8% and 31.5% at 2 and 3 years, respectively. Age ≥65 years (hazard ratio [HR]: 1.456; P = .002), lower resection rate (HR: 1.206; P < .001), recurrence (HR: 2.418; P < .001), and concomitant radiotherapy (HR: 0.588; P < .001) were identified as significant prognostic factors. CONCLUSIONS: This study confirmed the 2- and 3-year OS of Japanese malignant glioma patients with varied backgrounds after Gliadel implant. With a careful interpretation of indirect comparisons with previously reported data, the results suggest that prognosis could be improved with Gliadel implants. CLINICAL TRIAL REGISTRATION: NCT02300506.

[Molecular-Targeted Agents as a Novel Therapeutic Tool for Brain Metastases].

Brain metastases(BM)follow the nature of the primary cancer, and understanding the associated genomic abnormalities is essential in the construction of therapeutic strategies for BM. BM showed an excellent response to EGFR-TKI, but the duration of the effect was limited to approximately one year. Despite the longer survival of patients with EGFRm BM, these tumors tended to progress to leptomeningeal carcinomatosis(LMC), and the frequency of central nervous system death was higher than that of tumors without driver mutations. EGFR-TKI also had an effect on LMC and even improved hydrocephalus, but it achieved negative conversion of cancer cells in the cerebrospinal fluid in only limited cases. ALK-TKI also induced a good reduction of BM, and the duration of the response was quite long. Because the expected prognosis of patients after BM in ALK-positive cases is over 5 years, we should choose treatment modalities that are safe in the long term. The dominant cause of death in cancer patients is extracranial progression, and control of extracranial lesions should be prioritized, even in cases with BM. Therefore, the purpose of treatment of BM is to keep patients in a better condition and to maintain the indications for systemic treatment, and molecular-targeted agents, with both the safety and sufficient effectiveness, meet that demand.

Transcriptome and methylome analysis of CNS germ cell tumor finds its cell-of-origin in embryogenesis and reveals shared similarities with testicular counterparts.

BACKGROUND: CNS germ cell tumors (GCTs) predominantly develop in pediatric and young adult patients with variable responses to surgery, radiation, and chemotherapy. This study aimed to examine the complex and largely unknown pathogenesis of CNS GCTs. METHODS: We used a combined transcriptomic and methylomic approach in 84 cases and conducted an integrative analysis of the normal cells undergoing embryogenesis and testicular GCTs. RESULTS: Genome-wide transcriptome analysis in CNS GCTs indicated that germinoma had a transcriptomic profile representative of primitive cells during early embryogenesis with high meiosis/mitosis potentials, while nongerminomatous GCTs (NGGCTs) had differentiated phenotypes oriented toward tissue formation and organogenesis. Co-analysis with the transcriptome of human embryonic cells revealed that germinomas had expression profiles similar to those of primordial germ cells, while the expression profiles of NGGCTs were similar to those of embryonic stem cells. Some germinoma cases were characterized by extensive immune-cell infiltration and high expression of cancer-testis antigens. NGGCTs had significantly higher immune-cell infiltration, characterized by immune-suppression phenotype. CNS and testicular GCTs (TGCTs) had similar mutational profiles; TGCTs showed enhanced copy number alterations. Methylation analysis clustered germinoma/seminoma and nongerminoma/nonseminoma separately. Germinoma and seminoma were co-categorized based on the degree of the tumor microenvironment balance. CONCLUSIONS: These results suggested that the pathophysiology of GCTs was less dependent on their site of origin and more dependent on the state of differentiation as well as on the tumor microenvironment balance. This study revealed distinct biological properties of GCTs, which will hopefully lead to future treatment development.

12p gain is predominantly observed in non-germinomatous germ cell tumors and identifies an unfavorable subgroup of central nervous system germ cell tumors.

BACKGROUND: Central nervous system (CNS) germ cell tumors (GCTs) are neoplasms predominantly arising in pediatric and young adult populations. While germinomas generally respond to chemotherapy and radiation, non-germinomatous GCTs (NGGCTs) require more intensive treatment. This study aimed to determine whether 12p gain could predict the prognosis of CNS GCTs. METHODS: Eighty-two CNS GCTs were included in this study. The 12p gain was defined by an additional 12p in the background of potential polyploidy or polysomy. Cases were analyzed using an Illumina methylation 450K array for copy number investigations and validated by fluorescence in situ hybridization (FISH). RESULTS: A 12p gain was found in 25-out-of-82 cases (30%) and was more frequent in NGGCTs (12% of germinoma cases and 50% of NGGCT cases), particularly in cases with malignant components, such as immature teratoma, yolk sac tumor, choriocarcinoma, and embryonal carcinoma. 12p gain and KIT mutation were mutually exclusive events. The presence of 12p gain correlated with shorter progression-free (PFS) and overall survival (OS) (10-year OS: 59% vs. 94%, with and without 12p gain, respectively, P = 0.0002), even with histology and tumor markers incorporated in the multivariate analysis. Among NGGCTs, 12p gain still had prognostic significance for PFS and OS (10-year OS: 47% vs. 90%, respectively, P = 0.02). The 12p copy number status was shared among histological components in mixed GCTs. CONCLUSIONS: 12p gain may predict the presence of malignant components of NGGCTs, and poor prognosis of the patients. It may be associated with early tumorigenesis of CNS GCT.

Low tumor cell content predicts favorable prognosis in germinoma patients.

BACKGROUND: Germinoma preferentially occurs in pediatric and young adult age groups. Although they are responsive to treatment with chemotherapy and radiation, the treatment may cause long-term sequelae in their later lives. Here, we searched for clinical and histopathological features to predict the prognosis of germinoma and affect treatment response. METHODS: A total of 114 germinoma cases were included in the analysis. We investigated the association between clinical factors, tumor cell content, and progression-free survival (PFS). RESULTS: The tumor cell content was widely distributed from <5% to 90% in the specimens, with a median value of 50%. Female patients showed higher tumor cell content in the specimens (P = .002). Cases with lesions at atypical sites showed shorter PFS than those with lesions at other sites (P = .03). Patients with a higher tumor cell content (≥50%) showed shorter PFS than those with a lower tumor cell content (<50%) (P = .03). In multivariate analysis, tumor cell content was the only statistically significant prognostic factor (P = .04). Among the 7 cases treated with local radiation and chemotherapy, all 3 cases that recurred (2 outside of the radiation field, 1 unknown) had tumor cell content of ≥50% in the original specimen, whereas all 4 cases without recurrence had tumor cell contents of <50%. CONCLUSIONS: We found that tumor cell content significantly affected the prognosis of germinomas. Although validation of these results using an independent and larger cohort is necessary, this potentially opens the possibility of leveraging this pathological factor in future clinical trials when stratifying the treatment intensity.

Determining the extent of tumor resection at surgical planning with 18F-fluciclovine PET/CT in patients with suspected glioma: multicenter phase III trials.

OBJECTIVE: Glioma is the most common type of central nervous system tumor reported worldwide. Current imaging technologies have limitations in the diagnosis and assessment of glioma. The present study aimed to confirm the diagnostic efficacy and safety of anti-1-amino-3-[18F]fluorocyclobutane carboxylic acid (18F-fluciclovine; anti-[18F]FACBC) as a radiotracer for patients undergoing combined positron emission tomography and computed tomography (PET/CT) for suspected glioma. METHODS: Combined data from two multicenter, open-label phase III clinical trials were evaluated for this study. The two trials enrolled patients with suspected high- or low-grade glioma on the basis of clinical symptoms, clinical course, and magnetic resonance imaging findings, and who were scheduled for tumor resection surgery. Patients fasted for ≥ 4 h and received 2 mL of 18F-fluciclovine (radioactivity dose 78.3-297.0 MBq), followed by a 10-min PET scan 10-50 min after injection. The primary efficacy endpoint was the positive predictive value (PPV) of the gadolinium contrast-enhanced T1-weighted image negative [Gd (-)] and 18F-fluciclovine PET-positive [PET ( +)] area of the scans, using the histopathological diagnosis of the tissue sampled from that area as the standard of truth. All adverse events reported during the study were recorded for safety analysis. RESULTS: A total of 45 patients aged 23-89 years underwent 18F-fluciclovine PET; 31/45 patients (68.9%) were male, and 30/45 patients (66.7%) were suspected to have high-grade glioma. The PPV of 18F-fluciclovine PET in the Gd (-) PET ( +) area was 88.0% (22/25 areas, 95% confidence interval: 70.0-95.8). The extent of planned tumor resection was modified in 47.2% (17/36 cases) after 18F-fluciclovine PET scan, with an extension of area in 30.6% (11/36 cases) and reduction in 16.7% (6/36 cases). Furthermore, tissue samples collected from PET ( +) areas tended to have a higher malignancy grade compared with those from PET (-) areas. Overall, 18F-fluciclovine was well tolerated. CONCLUSION: 18F-fluciclovine PET/CT is useful for determining the extent of tumor resection at surgical planning, and may serve as a safe and effective diagnostic tool for patients with suspected glioma. TRIAL REGISTRATION: These trials were registered in the Japan Pharmaceutical Information Center Clinical Trials Information (JapicCTI-152986, JapicCTI-152985).

TERT promoter mutation confers favorable prognosis regardless of 1p/19q status in adult diffuse gliomas with IDH1/2 mutations.

TERT promoter mutations are commonly associated with 1p/19q codeletion in IDH-mutated gliomas. However, whether these mutations have an impact on patient survival independent of 1p/19q codeletion is unknown. In this study, we investigated the impact of TERT promoter mutations on survival in IDH-mutated glioma cases. Detailed clinical information and molecular status data were collected for a cohort of 560 adult patients with IDH-mutated gliomas. Among these patients, 279 had both TERT promoter mutation and 1p/19q codeletion, while 30 had either TERT promoter mutation (n = 24) or 1p/19q codeletion (n = 6) alone. A univariable Cox proportional hazard analysis for survival using clinical and genetic factors indicated that a Karnofsky performance status score (KPS) of 90 or 100, WHO grade II or III, TERT promoter mutation, 1p/19q codeletion, radiation therapy, and extent of resection (90-100%) were associated with favorable prognosis (p < 0.05). A multivariable Cox regression model revealed that TERT promoter mutation had a significantly favorable prognostic impact (hazard ratio = 0.421, p = 0.049), while 1p/19q codeletion did not have a significant impact (hazard ratio = 0.648, p = 0.349). Analyses incorporating patient clinical and genetic information were further conducted to identify subgroups showing the favorable prognostic impact of TERT promoter mutation. Among the grade II-III glioma patients with a KPS score of 90 or 100, those with IDH-TERT co-mutation and intact 1p/19q (n = 17) showed significantly longer survival than those with IDH mutation, wild-type TERT, and intact 1p/19q (n = 185) (5-year overall survival, 94% and 77%, respectively; p = 0.032). Our results demonstrate that TERT promoter mutation predicts favorable prognosis independent of 1p/19q codeletion in IDH-mutated gliomas. Combined with its adverse effect on survival among IDH-wild glioma cases, the bivalent prognostic impact of TERT promoter mutation may help further refine the molecular diagnosis and prognostication of diffuse gliomas.

Factors Linked to Prognosis in Patients with Leptomeningeal Metastasis Diagnosed by Spinal Magnetic Resonance Imaging.

INTRODUCTION: Leptomeningeal metastasis (LM) is known to demonstrate a very poor prognosis. The purpose of this study was to evaluate the prognostic factors in LM cases diagnosed by spinal magnetic resonance imaging (MRI). METHODS: We retrospectively analyzed 19 patients with LM detected by spinal MRI between 2010 and 2017. RESULTS: The primary tumors were breast carcinoma (n = 7), lung carcinoma (n = 6), lymphoma (n = 3), colorectal carcinoma (n = 2), and gastric carcinoma (n = 1). Thirteen patients exhibited preceding brain metastasis, and 11 of these exhibited metastasis in the posterior fossa. Ten patients exhibited limb paralysis. Performance status at diagnosis was 0-1 in 6 patients, 2 in 9 patients, and 3-4 in 4 patients. Testing of cerebrospinal fluid revealed malignant cells in 9 patients. On MRI, 11 patients demonstrated disseminated tumor lesions at the cervical cord level, 15 patients at the thoracic cord level, and 11 patients below the conus level. Eleven patients received radiation therapy, while intrathecal chemotherapy was performed in 9 patients. Univariate analysis revealed cervical cord level lesions, intrathecal chemotherapy, paralysis, and performance status as prognostic factors. Multivariate analysis identified existence of a cervical cord lesion as associated with a poor prognosis (hazards ratio (HR) 3.46, 95% confidence interval (CI) 1.12-12.2), while administration of intrathecal chemotherapy was associated with a good prognosis (HR 0.15, 95% CI 0.026-0.67). CONCLUSIONS: In LM patients, cervical cord level lesions are a negative factor for prognosis, and performance of intrathecal chemotherapy is a positive factor for prognosis.

Utility of a scoring system for differentiating cancer-associated stroke from cryptogenic stroke in patients with cancer.

BACKGROUND: The commonest type of ischemic cerebral stroke in patients with cancer is cryptogenic stroke (CRS), the majority of which are considered cancer-associated strokes (CAS) caused by multiple microemboli associated with hypercoagulation, known as Trousseau syndrome. However, detection of microemboli and diagnosing CAS is difficult. We have therefore developed a scoring system for diagnosing CAS. METHODS: We retrospectively examined data of patients with cancer and stroke between 2006 and 2017. We identified risk factors for CRS, assigned them one or two points, and calculated total scores (Trousseau score) for each patient. We used overall survival after stroke (OSs) to validate the utility of the system. RESULTS: In 181 consecutive strokes, CRS was the commonest type (43.6%) and had a short OSs (median 56 days). We identified the following five risks for CRS: high D-dimer concentration (≥ 10.0 µg/mL) and lesions in multiple territories (two points each); and active cancer, low platelet count (150,000/µL>) and female sex (one point each). Trousseau score ≥ 3 indicated CAS (50.3%), which had a median OSs of 50 days. Only CAS (hazard ratio 3.44 [2.34-5.10], P < 0.0001) and poor performance status (3 or 4) (2.27 [1.50-3.39], P = 0.0002) were risk factors for OSs; CRS was not. OSs of patients with non-CAS/CRS was significantly longer than that of those with CAS/CRS (404.5 days vs. 47 days, P = 0.0114), whereas OSs of CAS/non-CRS was much shorter than that of non-CAS/non-CRS (53 days vs. 547 days, P < 0.0001). CONCLUSION: Trousseau scores simply and clearly identify CAS.

Feasibility study of finalizing the extended adjuvant temozolomide based on methionine positron emission tomography (Met-PET) findings in patients with glioblastoma.

In the management of patients with newly diagnosed glioblastoma, there is no standard duration for adjuvant temozolomide treatment. This study aimed to assess the feasibility of finalizing adjuvant temozolomide treatment on the basis of methionine uptake in methionine positron emission tomography (Met-PET). We conducted a retrospective review of glioblastoma patients who underwent more than twelve cycles of temozolomide (extended temozolomide) treatment after resection and concomitant chemoradiotherapy with no evidence of recurrence on MRI. In addition to the methionine uptake value at the completion of extended temozolomide, local and distant recurrence and progression-free survival were also analyzed. Forty-four patients completed the extended temozolomide treatment. Among these, 18 experienced some type of tumor recurrence within one year. A Tmax/Nave value of 2.0 was the optimal cut-off value indicating progression. More than 80% of the patients with low methionine uptake completed the temozolomide treatment, and subsequent basic MRI observations showed no recurrence within one year after Met-PET. Subgroups with high uptake (≥2.0), even with continuation of temozolomide treatment, showed more frequent tumor progression than patients with low uptake (<2.0) who completed the extended temozolomide treatment (p < 0.001, odds ratio 14.7, 95% CI 3.46-62.3). The tumor recurrence rate increased in stepwise manner according to methionine uptake. Finalization of the extended temozolomide treatment on the basis of low uptake value was feasible with a low recurrence rate. Compared to MRI, Met-PET shows better ability to predict tumor progression in long-term glioblastoma survivors with extended temozolomide use.

Integrated clinical, histopathological, and molecular data analysis of 190 central nervous system germ cell tumors from the iGCT Consortium.

BACKGROUND: We integrated clinical, histopathological, and molecular data of central nervous system germ cell tumors to provide insights into their management. METHODS: Data from the Intracranial Germ Cell Tumor Genome Analysis (iGCT) Consortium were reviewed. A total of 190 cases were classified as primary germ cell tumors (GCTs) based on central pathological reviews. RESULTS: All but one of the cases that were bifocal (neurohypophysis and pineal glands) and cases with multiple lesions including neurohypophysis or pineal gland were germinomas (34 of 35). Age was significantly higher in patients with germinoma than other histologies. Comparison between tumor marker and histopathological diagnoses showed that 18.2% of histopathologically diagnosed germinomas were marker positive and 6.1% of non-germinomatous GCTs were marker negative, suggesting a limitation in the utility of markers or histopathology alone using small specimens for diagnosis. Comparison between local and central histopathological diagnoses revealed a discordance of 12.7%. Discordance was significantly less frequent in biopsy cases, implying difficulty in detecting all histopathological components of heterogeneous GCTs. Germinomas at the typical sites (neurohypophysis or pineal gland) showed a better progression-free survival than those at atypical sites (P = 0.03). A molecular clinical association study revealed frequent mitogen-activated protein kinase (MAPK) pathway mutations in males (51.4% vs 14.3%, P = 0.007), and phosphatidylinositol-3 kinase/mammalian target of rapamycin (PI3K/mTOR) pathway mutations in basal ganglia cases (P = 0.004). Basal ganglia cases also had frequent chromosomal losses. Some chromosomal aberrations (2q, 8q gain, 5q, 9p/q, 13q, 15q loss) showed potential prognostic significance. CONCLUSIONS: The in-depth findings of this study regarding clinical and molecular heterogeneity will increase our understanding of the pathogenesis of this enigmatic tumor.

Prognostic factors and survival in Japanese patients with brain metastasis from renal cell cancer.

BACKGROUND: Patients with brain metastasis from renal cell carcinoma have poor outcomes despite recent advances in diagnosis and treatment. Moreover, factors affecting such poor outcomes are unclear. This study aimed to evaluate the prognostic factors associated with overall survival in renal cell carcinoma patients with brain metastasis. METHODS: We retrospectively reviewed the data of 50 consecutive patients with brain metastasis from renal cell carcinoma at our institution between 1988 and 2017. The evaluated prognostic factors for overall survival included clinicopathological factors at diagnosis, treatment for brain metastasis, and the Graded Prognostic Assessment score of renal cell carcinoma. The associations between preoperative clinicopathological factors and overall survival were assessed using the log-rank test and Cox proportional hazards models for univariate and multivariate analyses, respectively. RESULTS: Forty-five patients were included, among whom 39 died during follow-up. The median follow-up was 8.2 months. The median survival time was 8.2 months (95% confidence interval 5.5-13.7). A Graded Prognostic Assessment score ≤ 2 (hazard ratio 1.967; 95% confidence interval 1.024-3.892; P = 0.042), the presence of sarcomatoid components (hazard ratio 3.299; 95% confidence interval 1.424-7.193; P = 0.007), and no treatment for brain metastasis (hazard ratio 2.594; 95% confidence interval 1.033-5.858; P = 0.043) were independently associated with poor prognosis in the multivariate analysis. CONCLUSIONS: Patients with renal cell carcinoma who develop brain metastasis have poor overall survival. The Graded Prognostic Assessment score, sarcomatoid components, and treatment for brain metastasis from renal cell carcinoma were independent factors associated with prognosis.

Clinical significance of the 2016 WHO classification in Japanese patients with gliomas.

In this study, we retrospectively compared the prognostic value of the 2016 WHO classification with the former classification in 387 patients with glioma treated at our institution. According to the new classification, diagnoses included oligodendroglioma with isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion (5.4%), anaplastic oligodendroglioma with IDH mutation and 1p/19q co-deletion (3.4%), diffuse astrocytoma IDH-mutated (3.9%), anaplastic astrocytoma IDH-mutated (2.8%), glioblastoma IDH-mutated (7.8%), glioblastoma IDH-wildtype (58.4%), diffuse midline glioma H3 K27M mutation (2.6%), oligodendroglioma NOS (1.3%), anaplastic oligodendroglioma NOS (0.8%), diffuse astrocytoma IDH-wildtype (2.8%), and anaplastic astrocytoma IDH-wildtype (10.9%). The prognoses of IDH-mutated astrocytomas clearly varied according to tumor grade. However, we identified no survival difference between IDH-wildtype anaplastic astrocytomas and glioblastomas; additionally, these tumors showed similar gene expression profiles. After exclusion of those without 1p/19q co-deletion, patients with oligodendroglial tumors showed excellent survival regardless of tumor grade. Our evaluation of chromosomal aberrations suggests that the MAPK/PI3K pathway plays a role in acquired malignancy of astrocytic tumors, whereas TP53 participates in tumorigenesis. We suspect the RB pathway also plays a role in tumorigenesis of IDH-mutated gliomas. The new WHO classification more clearly reflects the tumorigenesis of gliomas and improves the prognostic power of classification.

Diagnostic Performance and Safety of Positron Emission Tomography Using 18F-Fluciclovine in Patients with Clinically Suspected High- or Low-grade Gliomas: A Multicenter Phase IIb Trial.

OBJECTIVES: The study objective was to assess the diagnostic performance of positron emission tomography (PET) for gliomas using the novel tracer 18F-fluciclovine (anti-[18F]FACBC) and to evaluate the safety of this tracer in patients with clinically suspected gliomas. METHODS: Anti-[18F]FACBC was administered to 40 patients with clinically suspected high- or low-grade gliomas, followed by PET imaging. T1-weighted, contrast-enhanced T1-weighted, and fluid-attenuated inversion recovery (or T2-weighted) magnetic resonance imaging (MRI) scans were obtained to plan for the tissue collection. Tissues were collected from either "areas visualized using anti-[18F]FACBC PET imaging but not using contrast-enhanced T1-weighted imaging" or "areas visualized using both anti-[18F]FACBC-PET imaging and contrast-enhanced T1-weighted imaging" and were histopathologically examined to assess the diagnostic accuracy of anti-[18F]FACBC-PET for gliomas. RESULTS: The positive predictive value of anti-[18F]FACBC-PET imaging for glioma in areas visualized using anti-[18F]FACBC-PET imaging, but not visualized using contrast-enhanced T1-weighted images, was 100.0% (26/26), and the value in areas visualized using both contrast-enhanced T1-weighted imaging and anti-[18F]FACBC-PET imaging was 87.5% (7/8). Twelve adverse events occurred in 7 (17.5%) of the 40 patients who received anti-[18F]FACBC. Five events in five patients were considered to be adverse drug reactions; however, none of the events were serious, and all except one resolved spontaneously without treatment. CONCLUSION: This Phase IIb trial showed that anti-[18F]FACBC-PET imaging was effective for the detection of gliomas in areas not visualized using contrast-enhanced T1-weighted MRI and the tracer was well tolerated.

Genome-wide methylation profiles in primary intracranial germ cell tumors indicate a primordial germ cell origin for germinomas.

Intracranial germ cell tumors (iGCTs) are the second most common brain tumors among children under 14 in Japan. The World Health Organization classification recognizes several subtypes of iGCTs, which are conventionally subclassified into pure germinoma or non-germinomatous GCTs. Recent exhaustive genomic studies showed that mutations of the genes involved in the MAPK and/or PI3K pathways are common in iGCTs; however, the mechanisms of how different subtypes develop, often as a mixed-GCT, are unknown. To elucidate the pathogenesis of iGCTs, we investigated 61 GCTs of various subtypes by genome-wide DNA methylation profiling. We showed that pure germinomas are characterized by global low DNA methylation, a unique epigenetic feature making them distinct from all other iGCTs subtypes. The patterns of methylation strongly resemble that of primordial germ cells (PGC) at the migration phase, possibly indicating the cell of origin for these tumors. Unlike PGC, however, hypomethylation extends to long interspersed nuclear element retrotransposons. Histologically and epigenetically distinct microdissected components of mixed-GCTs shared identical somatic mutations in the MAPK or PI3K pathways, indicating that they developed from a common ancestral cell.

A prospective, multicentre, single-arm clinical trial of bevacizumab for patients with surgically untreatable, symptomatic brain radiation necrosis†.

BACKGROUND: Brain radiation necrosis (BRN) can be a complication of radiotherapy for primary and secondary brain tumors, as well as head and neck tumors. Since vascular endothelial growth factor (VEGF) is also a vascular permeability factor in the brain, bevacizumab, a humanized antibody that inhibits VEGF, would be expected to reduce perilesional edema that often accompanies BRN. METHODS: Patients with surgically untreatable, symptomatic BRN refractory to conventional medical treatments (eg, corticosteroid, anticoagulants, or hyperbaric oxygen therapy) were enrolled. We judged that a major cause of perilesional edema with a lesion-to-normal brain ratio ≤1.8 on 11C-methionine or ≤2.5 on 18F-boronophenylalanine PET was BRN, not tumor recurrence, and 6 cycles of biweekly bevacizumab (5 mg/kg) were administered. The primary endpoint was a ≥30% reduction from the patients' registration for perilesional edema continuing for ≥1 month. RESULTS: Of the 41 patients enrolled, 38 were fully eligible for the response assessment. The primary endpoint was achieved in 30 of the 38 (78.9%) patients at 3.0 months (median) after enrollment. Sixteen patients (42.1%) experienced improvement of their Karnofsy Performance Score. Corticosteroid use could be reduced in 29 patients (76.3%). Adverse events at grade ≥3 occurred in 10 patients (24.4%). CONCLUSIONS: Bevacizumab treatment offers certain clinical benefits for patients with surgically untreatable, symptomatic BRN. The determination of BRN using amino-acid PET, not biopsy, is adequate and less invasive for determining eligibility to receive bevacizumab.

The influence of carmustine wafer implantation on tumor bed cysts and peritumoral brain edema.

The development of perifocal edema and tumor bed cyst has been reported after implantation of biodegradable carmustine wafers for the treatment of malignant gliomas. We retrospectively evaluated these changes in a series of patients; 19 consecutive patients with malignant glioma who received carmustine wafer implantation at our hospital from January 2013 through July 2013, and 28 patients who underwent surgery prior to our institution's initiation of carmustine wafer implantation, as historical controls. The volume of the tumor bed cyst and perifocal edema was calculated on MRI acquired at four time points: ⩽72hours after surgery for baseline, and at 1-4, 5-8, and 9-12weeks after surgery. The volume of the tumor bed cyst in the wafer group increased significantly relative to the control group at all time points (p=0.04). Opening of the ventricle was inversely correlated with enlargement of the tumor bed cyst in the wafer group (p=0.04). The change in the volume of perifocal edema in the wafer group was not significantly different (p=0.48), but exhibited a considerable increase in patients with anaplastic oligodendroglioma relative to glioblastoma patients in the wafer group (p=0.01). We demonstrated significant enlargement of the tumor bed cyst volume after carmustine wafer implantation, as well as the development of marked perifocal edema in patients with anaplastic oligodendroglioma.

Recurrent neomorphic mutations of MTOR in central nervous system and testicular germ cell tumors may be targeted for therapy.

Germ cell tumors constitute a heterogeneous group that displays a broad spectrum of morphology. They often arise in testes; however, extragonadal occurrence, in particular brain, is not uncommon, and whether they share a common pathogenesis is unknown. We performed whole exome sequencing in 41 pairs of central nervous system germ cell tumors (CNS GCTs) of various histology and their matched normal tissues. We then performed targeted sequencing of 41 selected genes in a total of 124 CNS GCTs, 65 testicular germ cell tumors (tGCTs) and 8 metastatic GCTs to the CNS. The results showed that mutually exclusive mutations of genes involved in the MAPK pathway were most common (48.4 %), typically in KIT (27.4 %), followed by those in the PI3K pathway (12.9 %), particularly in MTOR (6.5 %), among the 124 CNS GCTs. Pure germinomas and non-germinomatous germ cell tumors (NGGCTs), as well as CNS and testicular GCTs, showed similar mutational profiles, suggesting that GCTs share a common molecular pathogenesis. Mutated MTOR identified in CNS GCTs upregulated phosphorylation of the AKT pathway proteins including AKT and 4EBP1 in nutrient-deprived conditions and enhanced soft-agar colony formation; both events were suppressed in a dose-dependent manner by addition of the MTOR inhibitor pp242. Our findings indicate that the dominant genetic drivers of GCTs regardless of the site of origin are activation of the MAPK and/or PI3K pathways by somatic point mutations. Mutated MTOR represents a potential target for novel targeted therapies for refractory GCTs.