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  • Author or Editor: Hiroshi Iseki x
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Mikhail Chernov, Yoshihiro Muragaki and Hiroshi Iseki

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Mikhail Chernov, Yoshihiro Muragaki and Hiroshi Iseki

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Takahiro Shioyama, Yoshihiro Muragaki, Takashi Maruyama, Takashi Komori and Hiroshi Iseki

Object

Intraoperative histopathological investigation plays an important role during surgery for gliomas. To facilitate the rapid characterization of resected tissue, an original technique of intraoperative flow cytometry (iFC) was established. The objective in this study was evaluation of this technique's efficacy for rapidly determining tumor presence in the surgical biopsy sample and WHO histopathological grade of the neoplasm.

Methods

In total, 328 separate biopsy specimens obtained during the resection of 81 intracranial gliomas were analyzed with iFC. The evaluated malignancy index (MI) was defined as the ratio of the number of cells with greater than normal DNA content to the total number of cells. The duration of iFC in all cases was approximately 10 minutes. Each sample was additionally investigated histopathologically on frozen and permanent formalin-fixed paraffin-embedded tissue sections. The latter process was used as a “gold standard” control for evaluation of the diagnostic efficacy of iFC analysis.

Results

The MI differed significantly between neoplastic and perilesional brain tissue (25.3% ± 22.0% vs 4.6% ± 2.6%, p < 0.01). Receiver operating characteristic curve analysis revealed a corresponding area under the curve value of 0.941. The optimal cutoff level of the MI for identification of tumor in the biopsy specimen was 6.8%, which provided 0.88 sensitivity, 0.88 specificity, 0.97 positive predictive value, 0.60 negative predictive value, and 0.88 diagnostic accuracy. Additionally, the MI showed a significant association with WHO histopathological grades of glioma (p < 0.01), but its values in Grade II, III, and IV tumors overlapped prominently and were on average 13.3% ± 11.0%, 35.0% ± 21.8%, and 46.6% ± 23.1%, respectively.

Conclusions

Results of this study demonstrate that iFC with the determination of the MI may be feasible for rapidly determining glioma presence in a surgical biopsy sample.

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Editorial

Our failure to advance new treatments for glioma to market

John H. Sampson, Thomas J. Kaminski and Kevin A. Schulman

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Yu Fujii, Yoshihiro Muragaki, Takashi Maruyama, Masayuki Nitta, Taiichi Saito, Soko Ikuta, Hiroshi Iseki, Kazuhiro Hongo and Takakazu Kawamata

OBJECTIVE

WHO Grade III gliomas are relatively rare and treated with multiple modalities such as surgery, chemotherapy, and radiotherapy. The impact of the extent of resection (EOR) on improving survival in patients with this tumor type is unclear. Moreover, because of the heterogeneous radiological appearance of Grade III gliomas, the MRI sequence that best correlates with tumor volume is unknown. In the present retrospective study, the authors evaluated the prognostic significance of EOR.

METHODS

Clinical and radiological data from 122 patients with newly diagnosed WHO Grade III gliomas who had undergone intraoperative MRI–guided resection at a single institution between March 2000 and December 2011 were analyzed retrospectively. Patients were divided into 2 groups by histological subtype: 81 patients had anaplastic astrocytoma (AA) or anaplastic oligoastrocytoma (AOA), and 41 patients had anaplastic oligodendroglioma (AO). EOR was calculated using pre- and postoperative T2-weighted and contrast-enhanced T1-weighted MR images. Univariate and multivariate analyses were performed to evaluate the prognostic significance of EOR on overall survival (OS).

RESULTS

The 5-, 8-, and 10-year OS rates for all patients were 74.28%, 70.59%, and 65.88%, respectively. The 5- and 8-year OS rates for patients with AA and AOA were 72.2% and 67.2%, respectively, and the 10-year OS rate was 62.0%. On the other hand, the 5- and 8-year OS rates for patients with AO were 79.0% and 79.0%; the 10-year OS rate is not yet available. The median pre- and postoperative T2-weighted high–signal intensity volumes were 56.1 cm3 (range 1.3–268 cm3) and 5.9 cm3 (range 0–180 cm3), respectively. The median EOR of T2-weighted high–signal intensity lesions (T2-EOR) and contrast-enhanced T1-weighted lesions were 88.8% (range 0.3%–100%) and 100% (range 34.0%–100%), respectively. A significant survival advantage was associated with resection of 53% or more of the preoperative T2-weighted high–signal intensity volume in patients with AA and AOA, but not in patients with AO. Univariate analysis showed that preoperative Karnofsky Performance Scale score (p = 0.0019), isocitrate dehydrogenase 1 (IDH1) mutation (p = 0.0008), and T2-EOR (p = 0.0208) were significant prognostic factors for survival in patients with AA and AOA. Multivariate analysis demonstrated that T2-EOR (HR 3.28; 95% CI 1.22–8.81; p = 0.0192) and IDH1 mutation (HR 3.90; 95% CI 1.53–10.75; p = 0.0044) were predictive of survival in patients with AA and AOA.

CONCLUSIONS

T2-EOR was one of the most important prognostic factors for patients with AA and AOA. A significant survival advantage was associated with resection of 53% or more of the preoperative T2-weighted high–signal intensity volume in patients with AA and AOA.

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George Vartholomatos, George A. Alexiou, Anna Batistatou, Athanassios P. Kyritsis and Spyridon Voulgaris

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Noriko Tamura, Motohiro Hayashi, Mikhail Chernov, Manabu Tamura, Ayako Horiba, Yoshiyuki Konishi, Yoshihiro Muragaki, Hiroshi Iseki and Yoshikazu Okada

Object

The focus of the present study was the evaluation of outcomes after unstaged and staged-volume Gamma Knife surgery (GKS) in children harboring intracranial arteriovenous malformations (AVMs).

Methods

Twenty-two children (median age 9.5 years) underwent GKS for AVMs and were followed up for at least 2 years thereafter. The disease manifested with intracranial hemorrhage in 77% of cases. In 68% of patients the lesion affected eloquent brain structures. The volume of the nidus ranged from 0.1 to 6.7 cm3. Gamma Knife surgery was guided mainly by data from dynamic contrast-enhanced CT scans, with preferential targeting of the junction between the nidus and draining vein. The total prescribed isodose volume was kept below 4.0 cm3, and the median margin dose was 22 Gy (range 20–25 Gy). If the volume of the nidus was larger than 4.0 cm3, a second radiosurgical session was planned for 3–4 years after the first one. Nine patients in the present series underwent unstaged radiosurgery, whereas staged-volume treatment was scheduled in 13 patients.

Results

Complete obliteration of the AVM was noted in 17 (77%) of 22 patients within a median period of 47 months after the last radiosurgical session. Complete obliteration of the lesion occurred in 89% of patients after unstaged treatment and in 62.5% after staged GKS. Four (67%) of 6 high-grade AVMs were completely obliterated. Complications included 3 bleeding episodes, the appearance of a region of hyperintensity on T2-weighted MR images in 2 patients who had no symptoms, and reappearance of the nidus in the vicinity of the completely obliterated AVM in 1 patient.

Conclusions

Radiosurgery is a highly effective management option for intracranial AVMs in children. For larger lesions, staged GKS may be applied successfully. Initial targeting of the nidus adjacent to the draining vein and application of a sufficient radiation dose to a relatively small volume (≤ 4 cm3) provides a good balance between a high probability of obliteration and a low risk of treatment-related complications.

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Masayuki Nitta, Yoshihiro Muragaki, Takashi Maruyama, Hiroshi Iseki, Takashi Komori, Soko Ikuta, Taiichi Saito, Takayuki Yasuda, Junji Hosono, Saori Okamoto, Shunichi Koriyama and Takakazu Kawamata

OBJECTIVE

In this study on the effectiveness and safety of photodynamic therapy (PDT) using talaporfin sodium and a semiconductor laser, the long-term follow-up results of 11 patients with glioblastoma enrolled in the authors’ previous phase II clinical trial (March 2009–2012) and the clinical results of 19 consecutive patients with newly diagnosed glioblastoma prospectively enrolled in a postmarket surveillance (March 2014–December 2016) were analyzed and compared with those of 164 patients treated without PDT during the same period.

METHODS

The main outcome measures were the median overall survival (OS) and progression-free survival (PFS) times. Moreover, the adverse events and radiological changes after PDT, as well as the patterns of recurrence, were analyzed and compared between the groups. Kaplan-Meier curves were created to assess the differences in OS and PFS between the groups. Univariate and multivariate analyses were performed to identify the prognostic factors, including PDT, among patients with newly diagnosed glioblastoma.

RESULTS

The median PFS times of the PDT and control groups were 19.6 and 9.0 months, with 6-month PFS rates of 86.3% and 64.9%, respectively (p = 0.016). The median OS times were 27.4 and 22.1 months, with 1-year OS rates of 95.7% and 72.5%, respectively (p = 0.0327). Multivariate analyses found PDT, preoperative Karnofsky Performance Scale score, and IDH mutation to be significant independent prognostic factors for both OS and PFS. Eighteen of 30 patients in the PDT group experienced tumor recurrence, including local recurrence, distant recurrence, and dissemination in 10, 3, and 4 patients, respectively. Conversely, 141 of 164 patients in the control group experienced tumor recurrence, including 101 cases of local recurrence. The rate of local recurrence tended to be lower in the PDT group (p = 0.06).

CONCLUSIONS

The results of the present study suggest that PDT with talaporfin sodium and a semiconductor laser provides excellent local control, with few adverse effects even in cases of multiple laser irradiations, as well as potential survival benefits for patients with newly diagnosed glioblastoma.

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Yoshihiro Muragaki, Ken Masamune, Miyuki Uematsu, Mitsuo Umezu, Hiroshi Iseki and Mikhail Chernov

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Taiichi Saito, Yoshihiro Muragaki, Takashi Maruyama, Manabu Tamura, Masayuki Nitta, Shunsuke Tsuzuki, Yoshiyuki Konishi, Kotoe Kamata, Ryuta Kinno, Kuniyoshi L. Sakai, Hiroshi Iseki and Takakazu Kawamata

OBJECTIVE

Identification of language areas using functional brain mapping is sometimes impossible using current methods but essential to preserve language function in patients with gliomas located within or near the frontal language area (FLA). However, the factors that influence the failure to detect language areas have not been elucidated. The present study evaluated the difficulty in identifying the FLA in dominant-side frontal gliomas that involve the pars triangularis (PT) to determine the factors that influenced failed positive language mapping.

METHODS

Awake craniotomy was performed on 301 patients from April 2000 to October 2013 at Tokyo Women's Medical University. Recurrent cases were excluded, and patients were also excluded if motor mapping indicated their glioma was in or around the motor area on the dominant or nondominant side. Eighty-two consecutive cases of primary frontal glioma on the dominant side were analyzed for the present study. MRI was used for all patients to evaluate whether tumors involved the PT and to perform language functional mapping with a bipolar electrical stimulator. Eighteen of 82 patients (mean age 39 ± 13 years) had tumors that showed involvement of the PT, and the detailed characteristics of these 18 patients were examined.

RESULTS

The FLA could not be identified with intraoperative brain mapping in 14 (17%) of 82 patients; 11 (79%) of these 14 patients had a tumor involving the PT. The negative response rate in language mapping was only 5% in patients without involvement of the PT, whereas this rate was 61% in patients with involvement of the PT. Univariate analyses showed no significant correlation between identification of the FLA and sex, age, histology, or WHO grade. However, failure to identify the FLA was significantly correlated with involvement of the PT (p < 0.0001). Similarly, multivariate analyses with the logistic regression model showed that only involvement of the PT was significantly correlated with failure to identify the FLA (p < 0.0001). In 18 patients whose tumors involved the PT, only 1 patient had mild preoperative dysphasia. One week after surgery, language function worsened in 4 (22%) of 18 patients. Six months after surgery, 1 (5.6%) of 18 patients had a persistent mild speech deficit. The mean extent of resection was 90% ± 7.1%.

Conclusions

Identification of the FLA can be difficult in patients with frontal gliomas on the dominant side that involve the PT, but the positive mapping rate of the FLA was 95% in patients without involvement of the PT. These findings are useful for establishing a positive mapping strategy for patients undergoing awake craniotomy for the treatment of frontal gliomas on the dominant side. Thoroughly positive language mapping with subcortical electrical stimulation should be performed in patients without involvement of the PT. More careful continuous neurological monitoring combined with subcortical electrical stimulation is needed when removing dominant-side frontal gliomas that involve the PT.