Residual diffusion-weighted imaging hyperintense signal in primary central nervous system lymphoma can predict early recurrence.

BACKGROUND: The treatment response of primary central nervous system lymphomas (PCNSLs) is mainly evaluated using postcontrast T1-weighted imaging (T1WI). Because poorly enhanced lesions may contain residual tumors, the combination of evaluation methods will potentially improve the accuracy of determining treatment effectiveness. In this study, we evaluated the usefulness of diffusion-weighted imaging (DWI) in predicting recurrence among patients with PCNSL who achieved complete response (CR)/unconfirmed CR (CRu). METHODS: Fifty-four patients newly diagnosed with PCNSL who were treated at our institution and achieved CR/CRu at the end of treatment were included in this study. The patients were divided into two groups according to the presence or absence of residual DWI hyperintense signal at the tumor site at the end of treatment. Kaplan-Meier analysis was performed to analyze the median overall survival (OS) and progression-free survival (PFS). RESULTS: The mean age of the 54 patients was 66.4 ± 13.3 years. The induction therapies were HD-MTX in 20 patients, R-MPV in 29 patients, and other chemotherapies in five patients. Radiotherapy was performed in 35 patients, high-dose cytarabine therapy in 14 patients, and autologous hematopoietic stem cell transplantation in one patient, and of the 54 patients, 10 had no consolidation therapy. The residual DWI hyperintense signal sign was observed in 18 patients. The R-MPV regimen was statistically associated with a lower rate of residual DWI hyperintense signal (p = 0.0453). The median PFS was statistically shorter in the residual DWI hyperintense signal group than in the non-residual DWI hyperintense signal group (14.0 months vs. 85.1 months) (p < 0.0001, log-rank test). CONCLUSION: A residual DWI hyperintense signal at the end of treatment was statistically associated with shorter PFS. Among patients who achieved CR/CRu evaluated based on postcontrast T1WI, DWI could be a valuable additional sequence to predict the early recurrence of PCNSL.

Secondary meningioma after cranial irradiation: case series and comprehensive literature review.

BACKGROUND: Secondary meningioma after cranial irradiation, so-called radiation-induced meningioma, is one of the important late effects after cranial radiation therapy. In this report, we analyzed our case series of secondary meningioma after cranial irradiation and conducted a critical review of literature to reveal the characteristics of secondary meningioma. MATERIALS AND METHODS: We performed a comprehensive literature review by using Pubmed, MEDLINE and Google scholar databases and investigated pathologically confirmed individual cases. In our institute, we found pathologically diagnosed seven cases with secondary meningioma between 2000 and 2018. Totally, 364 cases were analyzed based on gender, WHO grade, radiation dose, chemotherapy. The latency years from irradiation to development of secondary meningioma were analyzed with Kaplan-Meier analysis. Spearman's correlation test was used to determine the relationship between age at irradiation and the latency years. RESULTS: The mean age at secondary meningioma development was 35.6 ± 15.7 years and the mean latency periods were 22.6 ± 12.1 years. The latency periods from irradiation to the development of secondary meningioma are significantly shorter in higher WHO grade group (P = 0.0026, generalized Wilcoxon test), higher radiation dose group (P < 0.0001) and concomitant systemic chemotherapy group (P = 0.0003). Age at irradiation was negatively associated with the latency periods (r = -0.23231, P < 0.0001, Spearman's correlation test). CONCLUSION: Cranial irradiation at older ages, at higher doses and concomitant chemotherapy was associated with a shorter latency period to develop secondary meningiomas. However, even low-dose irradiation can cause secondary meningiomas after a long latency period. Long-term follow-up is necessary to minimize the morbidity and mortality caused by secondary meningioma after cranial irradiation.

Characteristics and therapeutic strategies of brain and cranial radiation-induced sarcoma: analysis of 165 cases from our case experience and comprehensive review.

BACKGROUND: Radiation-induced sarcoma (RIS) is among the neoplasms potentially caused by radiation therapy (RT) for brain tumors. However, the clinical characteristics of and ideal treatment for RIS are unclear. We analysed our case experience and conducted a comprehensive literature review to reveal the characteristics of brain and cranial RIS. METHODS: We analysed 165 cases of RIS from the literature together with the RIS case treated at our institution. In each case, the latency period from irradiation to the development of each RIS and the median overall survival (OS) of the patients was analysed by Kaplan-Meier analysis. Spearman's correlation test was used to determine the relationship between the latency period and radiation dose or age at irradiation. RESULTS: The mean age at the development of RIS was 39.63 ± 17.84 years. The mean latency period was 11.79 ± 8.09 years. No factors associated with early development of RIS were detected. The median OS was 11 months, with fibrosarcoma showing significantly shorter OS compared with osteosarcoma and other sarcomas (p = 0.0021), and intracranial RIS showing a worse prognosis than extracranial RIS (p < 0.0001). Patients treated with surgery (p < 0.0001) and postoperative chemotherapy (p = 0.0157) for RIS presented significantly longer OS, whereas RT for RIS was not associated with a survival benefit. CONCLUSIONS: Although prognosis for RIS is universally poor, pathological characteristics and locations are associated with worse prognosis. Surgery and chemotherapy may be the ideal treatment strategies for RIS.

Characteristics and therapeutic strategies of radiation-induced glioma: case series and comprehensive literature review.

INTRODUCTION: The so-called radiation-induced glioma (RIG, a secondary glioma after cranial irradiation), is a serious late effect after cranial radiation therapy. The clinical characteristics of and ideal treatment for these tumors are unclear. We analyzed our case series and conducted a comprehensive literature review to reveal the precise characteristics of RIGs. METHODS: We analyzed the cases of six patients with RIGs treated at our institution and 354 patients with RIGs from the literature. The latency period from irradiation to the development of each RIG and the median overall survival of the patients were subjected to Kaplan-Meier analyses. Spearman's correlation test was used to determine the relationship between age at irradiation and the latency period. RESULTS: The mean age of the 360 patients at the development of RIG was 27.42 ± 17.87 years. The mean latency period was 11.35 ± 8.58 years. Multiple gliomas were observed in 28.4%. WHO grade 3 and 4 RIGs accounted for 93.3%. The latency periods were significant shorter in the higher WHO grade group (p = 0.0366) and the concomitant systemic chemotherapy group (p < 0.0001). Age at irradiation was negatively associated with the latency period (r =- 0.2287, p = 0.0219). The patients treated with radiotherapy achieved significantly longer survival compared to those treated without radiotherapy (p = 0.0011). CONCLUSIONS: Development in younger age, multiplicity, and high incidence of grade 3 and 4 are the clinical characteristics of RIGs. Cranial irradiation at older ages and concomitant chemotherapy were associated with shorter latency for the development of RIG. Radiation therapy may be the feasible treatment option despite radiation-induced gliomas.

Impacts of genotypic variants on survival following reoperation for recurrent glioblastoma.

INTRODUCTION: Recurrent glioblastoma (rGBM) prognosis is dismal. In the absence of effective adjuvant treatments for rGBM, re-resections remain prominent in our arsenal. This study evaluates the impact of reoperation on post-progression survival (PPS) considering rGBM genetic makeup. METHODS: To assess the genetic heterogeneity and treatment-related changes (TRC) roles in re-operated or medically managed rGBMs, we compiled demographic, clinical, histopathological, and next-generation genetic sequencing (NGS) characteristics of these tumors from 01/2005 to 10/2019. Survival data and reoperation were analyzed using conventional and random survival forest analysis (RSF). RESULTS: Patients harboring CDKN2A/B loss (p = 0.017) and KDR mutations (p = 0.031) had notably shorter survival. Reoperation or bevacizumab were associated with longer PPS (11.2 vs. 7.4-months, p = 0.006; 13.1 vs 6.2, p < 0.001). Reoperated patients were younger, had better performance status and greater initial resection. In 136/273 (49%) rGBMs undergoing re-operation, CDKN2A/B loss (p = 0.03) and KDR mutations (p = 0.02) were associated with shorter survival. In IDH-WT rGBMs with NGS data (n = 166), reoperation resulted in 7.0-month longer survival (p = 0.004) than those managed medically. This reoperation benefit was independently identified by RSF analysis. Stratification analysis revealed that EGFR-mutant, CDKN2A/B-mutant, NF1-WT, and TP53-WT rGBM IDH-WT subgroups benefit most from reoperation (p = 0.03). Lastly, whether or not TRC was prominent at re-operation does not have any significant impact on PPS (10.5 vs. 11.5-months, p = 0.77). CONCLUSIONS: Maximal safe re-resection significantly lengthens PPS regardless of genetic makeup, but reoperations are especially beneficial for IDH-WT rGBMs with EGFR and CDKN2A/B mutations with TP53-WT, and NF1-WT. Histopathology at recurrence may be an imperfect gauge of disease severity at progression and the imaging progression may be more reflective of the prognosis.

Influence of growth hormone therapy on germinoma survivors.

PURPOSE: Due to the effectiveness of growth hormone therapy (GHT), the number of cancer survivors receiving GHT has increased. Previous studies had indicated that GHT was not associated with the increasing risks of tumor recurrence and development with second neoplasm (SN) in cancer survivors. However, to date, research on those risks in germinoma survivors is still limited. The aim of this study is to evaluate the impact of GHT in relation to tumor recurrence and development with SN in pure germinoma survivors. METHODS: This retrospective cohort study was approved by the Ethical Committee for Epidemiology of our institution. Seventy-three consecutive patients who underwent a biopsy of the lesion and were diagnosed with pure germinoma were retrospectively studied. They (median age, 15.0 years) were followed up more than 1 year after biopsy (median follow-up period, 14.3 years). The following data was obtained from the medical records of the patients: age, sex, preoperative magnetic resonance imaging findings, hormonal replacement, and events including tumor recurrence and/or SN. RESULTS: In our patient series, 16 patients (21.9%) who were more likely to have neurohypophysial lesion and receive multiple hormonal therapies had received GHT. No significant differences in the rates of tumor recurrence and development with SN were observed between the patients who had and had not received GHT. Moreover, the recurrence-free survival and overall survival rates were not different between the patients who had and had not received GHT. CONCLUSIONS: GHT did not increase the risks of tumor recurrence and development with SN in pure germinoma survivors.

PTEN mutations predict benefit from tumor treating fields (TTFields) therapy in patients with recurrent glioblastoma.

INTRODUCTION: Optimal treatment for recurrent glioblastoma isocitrate dehydrogenase 1 and 2 wild-type (rGBM IDH-WT) is not standardized, resulting in multiple therapeutic approaches. A phase III clinical trial showed that tumor treating fields (TTFields) monotherapy provided comparable survival benefits to physician's chemotherapy choice in rGBM. However, patients did not equally benefit from TTFields, highlighting the importance of identifying predictive biomarkers of TTFields efficacy. METHODS: A retrospective review of an institutional database with 530 patients with infiltrating gliomas was performed. Patients with IDH-WT rGBM receiving TTFields at first recurrence were included. Tumors were evaluated by next-generation sequencing for mutations in 205 cancer-related genes. Post-progression survival (PPS) was examined using the log-rank test and multivariate Cox-regression analysis. RESULTS: 149 rGBM patients were identified of which 29 (19%) were treated with TTFields. No significant difference in median PPS was observed between rGBM patients who received versus did not receive TTFields (13.9 versus 10.9 months, p = 0.068). However, within the TTFields-treated group (n = 29), PPS was improved in PTEN-mutant (n = 14) versus PTEN-WT (n = 15) rGBM, (22.2 versus 11.6 months, p = 0.017). Within the PTEN-mutant group (n = 70, 47%), patients treated with TTFields (n = 14) had longer median PPS (22.2 versus 9.3 months, p = 0.005). No PPS benefit was observed in PTEN-WT patients receiving TTFields (n = 79, 53%). CONCLUSIONS: TTFields therapy conferred a significant PPS benefit in PTEN-mutant rGBM. Understanding the molecular mechanisms underpinning the differences in response to TTFields therapy could help elucidate the mechanism of action of TTFields and identify the rGBM patients most likely to benefit from this therapeutic option.

Variable expression of CXCR4 in molecular subtypes of infiltrating gliomas.

AIM: Glioblastomas (GBMs) and diffuse intrinsic pontine gliomas (DIPGs) are infiltrating gliomas with poor prognosis. CXCR4 has been linked to glioma cell invasion, survival, proliferation, and angiogenesis. This study aimed to evaluate the expression of CXCR4 in molecular subtypes of adult and pediatric infiltrating gliomas. MATERIALS AND METHODS: We evaluated the expression of CXCR4 in 21 DIPGs and 44 adult infiltrating gliomas (25 GBM, 8 astrocytomas, and 11 oligodendrogliomas) by immunohistochemistry. Mutations in 315 cancer genes and rearrangements in 28 genes were evaluated by next-generation sequencing. RESULTS: CXCR4 was expressed in -DIPGs and adult infiltrating gliomas in tumor cells (28.6% and 5.6%, respectively) and endothelial cells (14.3% and 19.4%?, respectively). In adult gliomas, there was a correlation between CXCR4 expression and mutations in EGFR, PIK3CA, TERT promoter, and CDKN2A/B loss. In contrast, CXCR4 expression was not detected in IDH1/IDH2 mutant gliomas. These associations were confirmed using The Cancer Genome Atlas (TCGA) database. CONCLUSION: CXCR4 is expressed in a subset of DIPGs and GBMs, but it is not expressed in astrocytomas or oligodendrogliomas. CXCR4 expression is variable and it is influenced by tumor genomic alterations. It is important to consider CXCR4 expression in clinical trials that evaluate the efficacy of CXCR4 inhibitors in the treatment of gliomas.

[Elderly Glioma].

Treatment of elderly glioma patients is a challenge in neurosurgery/neuro-oncology. The International Society of Geriatric Oncology(SIOG)recommends that elderly cancer patients undergo comprehensive geriatric assessment(CGA). The CGA score proved to be a significant predictor of mortality in this cohort, and it could be a useful treatment decision tool. Because of the rapid aging of Japan's population, clinical research focusing on elderly patients with cancer is urgently needed. The Japan Clinical Oncology Group(JCOG)has established a formal policy for research in geriatric cancers. Currently, the JCOG recommends that researchers perform CGA, including G8, to assess the tolerability of treatment for clinical trials in elderly cancer patients, including glioma. Under this policy, elderly cancer patients are categorized into three groups: fit, vulnerable, and frail. For "unfit" glioma/glioblastoma patients, physicians will need to conduct appropriately reduced treatment. Hypofractionated radiotherapy(40.05 Gy/15 fractions)has been an established treatment for elderly patients with glioblastoma. The concurrent and adjuvant temozolomide have reported to have a survival benefit for "fit" elderly patients. Subsequently, alternative hypofractionated radiotherapy, including 34 Gy/10 fractions and monotherapy with temozolomide against MGMT methylated glioblastomas, have been reported as non-inferior alternative treatments. Physicians also need to consider the adverse events associated with anticonvulsants.

Additional genetic alterations in BRAF-mutant gliomas correlate with histologic diagnoses.

INTRODUCTION: Recently, the term "Diffuse glioma, BRAF V600E-mutant" has been recommended for IDH-wildtype gliomas with BRAF p.V600E mutation and without CDKN2A/B deletion. However, additional alterations in gliomas that coexist with BRAF-mutations are poorly defined. METHODS: We analyzed next-generation sequencing results in 315 cancer-associated genes for 372 gliomas from our institution (2010 to 2017). In addition, we reviewed IDH-WT gliomas with mutation and copy-number alterations available in cBioPortal, to further characterize BRAF-mutant gliomas. RESULTS: Seventeen (4.6%) showed BRAF mutations. Tumor types included 8 glioblastomas, 2 epithelioid glioblastomas (E-GBM), 2 pleomorphic xanthoastrocytomas (PXA), 1 anaplastic oligodendroglioma, 1 diffuse astrocytoma, and 3 pilocytic astrocytomas. Fifty-three percent (53%) of cases exhibited BRAF-alterations other than p.V600E. The majority of the tumors were localized in the temporal lobe (52.9%). In addition to BRAF mutations, glioblastomas showed concomitant mutations in TP53 (3/8), CDKN2A/B-loss (6/8), TERT-promoter (6/8), and/or PTEN (5/8). Both E-GBMs and PXAs showed CDKN2A/B-loss and BRAF p.V600E with absence of TERTp, TP53, and PTEN mutations. Similar findings were observed in BRAF-mutant infiltrating gliomas from cBioPortal. CONCLUSIONS: Knowledge of additional alterations that co-occur with BRAF-mutations in gliomas may improve diagnosis and help identify patients that could benefit from targeted therapies. Furthermore, we provide examples of two patients whose tumors responded to BRAF pathway inhibitors, arguing in favor of these therapies in patients with BRAF-mutant gliomas.

Immunostaining of Increased Expression of Enhancer of Zeste Homolog 2 (EZH2) in Diffuse Midline Glioma H3K27M-Mutant Patients with Poor Survival.

INTRODUCTION: The interaction of K27M mutation in histone H3 (H3K27M mutation) with polycomb repressive complex 2 (PRC2) is facilitated by the enhancer of zeste homolog 2 (EZH2). Subsequently, this interaction leads to the global reduction level of H3K27me3. We analyzed the EZH2 expression level in H3K27M mutation-positive tumors and revealed the association of high EZH2 expression with poor survival. METHODS: Our study included 12 patients, with an age range of 6-56 years and treated between 2007 and 2016. All patients underwent MRI study for nonenhanced T1, T2, diffusion, gadolinium-enhanced T1-weighted imaging, and fluid-attenuated inversion recovery (FLAIR). Immunohistochemical staining was performed against H3K27M, H3K27me3, EZH2, EED, mutant isocitrate dehydrogenase 1 (IDH1), α-thalassemia X-linked intellectual disability (ATRX), p53, O6-methylguanine-DNA methyltransferase (MGMT), and Ki-67 antibodies. RESULTS: All patients were negative for IDH1R132H and H3K27me3, but H3K27M-positive. Staining against EZH2 was negative in all histological features of grade II cases (3/12) and positive in grade III and IV cases; EZH2 positivity is associated with poor prognosis (p = 0.0082). EZH2 positivity was not associated with EED positivity. Retained ATRX staining was found mostly in grade III and IV cases (6/12). P53 was predominantly positive in cases of astrocytoma and glioblastoma (8/12). The labeling index of Ki-67 was 1.2-31.4% for grade II and III histological features and 11.2-24.8% for grade IV. CONCLUSION: We suggest that the expression of EZH2 is not associated with the PRC2 pathway and increases in patients with H3K27M-mutant diffuse midline glioma and a poor prognosis. Further studies are necessary to understand the mechanism involved.

[Weekly Vinblastine in Pediatric Optic Pathway/Hypothalamic Glioma:2 Cases Report].

It is reported that vinblastine monotherapy has promising activity in patients with pediatric optic pathway/hypothalamic glioma(OPHG)who experienced treatment failure after initial treatment with standard chemotherapy. However, there have been no reports on vinblastine monotherapy against OPHG in Japan. Since vinblastine is an unauthorized drug under the Ministry of Health and Welfare, we used it after completing an in-hospital institutional review board application for each case. In the first case, a 6-year-old boy with recurrent OPHG with hydrocephalus was referred to our hospital. Weekly vinblastine was started at a dose of 6mg/m2 and was then reduced to 5mg/m2 and 4mg/m2 sequentially due to hematotoxicity. After 11 cycles of vinblastine, improvement in hydrocephalus was observed. After 22 cycles of vinblastine, the best response was observed, and we continued treatment up to 35 cycles. Progression of the disease was observed after 47 cycles and then we changed treatment to another regimen after 48 cycles of vinblastine. In the second case, a 6-year-old boy with chemotherapy-naïve recurrent OPHG underwent chemotherapy with vincristine and carboplatin. After 9 treatment cycles with carboplatin, hypersensitivity was observed. Subsequently, he was treated using weekly vinblastine as per the same protocol as that in our first case. A moderate response was observed after 18 cycles of vinblastine. After 48 cycles of vinblastine, the best response was observed, and we completed treatment. In both cases, severe adverse events were not observed and the treatment was well-tolerated. Vinblastine administered once per week is well-tolerated and maintains quality of life in children with OPHG.

Prognostic importance of temozolomide-induced neutropenia in glioblastoma, IDH-wildtype patients.

Standard treatment for patients with primary glioblastoma (GBM) includes surgery, radiotherapy, and concomitant and adjuvant temozolomide (TMZ). Recent reports have demonstrated that TMZ-induced myelosuppression correlates with survival in patients with GBM. However, those results were evaluated before the 2016 revision of the World Health Organization classification. This study examined whether myelosuppression during concomitant TMZ phase correlates with prognosis in GBM, IDH-wildtype patients. We examined circulating blood cell counts in 50 patients with GBM, IDH-wildtype who received the standard treatment protocol between August 2005 and November 2015. We assessed relationships between rates of decrease in blood cells (white blood cells (WBC), neutrophils, lymphocytes, red blood cells, and platelets) during the concomitant TMZ phase and overall survival (OS) using univariate and multivariate analyses including other clinicopathological factors (age, sex, Karnofsky Performance Status (KPS), extent of resection, O6-methylguanine-DNA methyltransferase (MGMT) status). Log-rank testing revealed that age, KPS, extent of resection, MGMT status, and decrease rates of WBC, neutrophils, and platelets correlated significantly with OS. On multivariate analysis, age, MGMT status, and decrease rate of neutrophils correlated significantly with OS. Patients with a ≥ 40% decrease in neutrophils showed significantly longer OS than those with < 40% (hazard ratio = 2.815; 95% confidence interval = 1.177-7.038; P = 0.0196). A decrease of ≥ 40% in neutrophils represents a predictor of good prognosis for GBM, IDH-wildtype. Blood cell counts during the concomitant TMZ phase can help predict OS in patients with GBM, IDH-wildtype receiving the standard treatment protocol.

Multicentric Glioma Develops via a Mutant IDH1-Independent Pathway: Immunohistochemical Study of Multicentric Glioma.

Multicentric gliomas are very rare. Due to differences in their tumor types they remain enigmatic. We focused on the pathogenesis of multicentric gliomas and compared their immunoprofile with that of solitary gliomas. This retrospective study included 6 males and 8 females with multicentric glioma (8 glioblastomas, 2 anaplastic astrocytomas, 4 diffuse astrocytomas). Their age ranged from 27 to 75 years and all were treated between 2004 and June 2015. The expression of mutant isocitrate dehydrogenase 1 (IDH1), α-thalassemia X-linked intellectual disability (ATRX), p53, phosphatase and tensin homolog (PTEN), and epidermal growth factor receptor (EGFR) was examined immunohistochemically; for 1p19q analysis we used fluorescence in situ hybridization (FISH). In all patients, immunohistochemical staining was negative for mutant IDH1 and cytoplasmic PTEN; only 1 patient (7.1%) manifested nuclear PTEN positivity. FISH for 1p19q codeletion was negative in all 9 examined samples; 5 of 14 specimens (35.7%) were p53-positive, 9 (64.3%) were EGFR-positive, and 4 (28.6%) were ATRX-negative. The MIB-1 labeling index was 0.9-15.6% for grades II and III, and ranged between 17.3 and 52.4% for glioblastoma. Our results suggest that the pathogenesis of multicentric gliomas is different from the mutant IDH1-R132H pathogenesis of lower-grade glioma and secondary glioblastomas. More studies are needed to confirm the molecular mechanisms underlying the pathogenesis of multicentric glioma.

Diffuse leptomeningeal glioneuronal tumor (DLGNT) mimicking Whipple's disease: a case report and literature review.

INTRODUCTION: Diffuse leptomeningeal glioneuronal tumor is a new entity under the neuronal and mixed neuronal-glial tumors in the WHO 2016 updated classification and commonly found in children and adolescents. The initial diagnosis is challenging because of its non-specific radiologic feature and negative CSF cytology analysis. A 17 years male was presented with intractable headache subsequently followed by back pain and joint pain. MRI showed enhancement of arachnoid membrane at basal cistern, bilateral sylvian fissure and cerebral cistern with slight enlargement of ventricles. There were no evidences of infection in CSF and blood samples. Based on the duodenal biopsy and prodromal symptom of joint pain, the patient was suspected of having Whipple's disease. Eleven months after the onset, a small mass lesion was observed at the anterior horn of right lateral ventricle. The histology was remarkable for anaplastic oligodendroglioma. Immunostainings revealed positivity for GFAP, Olig2, synaptophysin and negativity for IDH1 mutation, H3K27M. MIB1 labeling index was 40% and 1p19q FISH analysis showed only 1p deletion. Therefore, a final diagnosis of DLGNT was made. CONCLUSION: DLGNT should be included as a differential diagnosis of patients with leptomeningeal-enhanced and high CSF protein level with normal white blood cell count.

Development of cystic malacia after high-dose cranial irradiation of pediatric CNS tumors in long-term follow-up.

PURPOSE: The purpose of this study is to investigate the incidence of cystic malacia in long-term survivors of pediatric brain tumors treated with high-dose cranial irradiation. MATERIALS AND METHODS: Between 1997 and 2015, we treated 41 pediatric patients (26 males, 15 females; age ranging from 3.3 to 15.7 years, median 9-year-old) of pediatric brain tumors [17 medulloblastomas, 7 primitive neuroectodermal tumors (PNET), 3 pineoblastomas, 6 non-germinomatous germ cell tumors (NGGCT), 8 gliomas (including 4 ependymomas, 1 anaplastic astrocytoma, 1 oligodendroglioma, 1 pilocytic astrocytoma, 1 astroblastoma)] with high-dose craniospinal irradiation. Follow-up ranged from 14.0 to 189.2 months (median 86.0 months, mean 81.5 months), the irradiation dose to the whole neural axis ranged from 18 to 41.4 Gy, and the total local dose from 43.2 to 60.4 Gy. All patients underwent follow-up magnetic resonance imaging (MRI) studies at least once a year. Diagnosis of cystic malacia was based solely on MRI findings. Of the 41 patients, 31 were censored during their follow-up due to recurrence of the primary disease (n = 5), detection of secondary leukemia after development of cystic malacia (n = 1), or the absence of cystic malacia on the last follow-up MRI study (n = 25). We also evaluated the development of post-irradiation cavernous angioma and white matter changes. RESULTS: Following irradiation treatment, 11 patients developed 19 cystic malacia during a median course of 30.8 months (range 14.9 to 59.3 months). The site of predilection for cystic malacia was white matter around trigone of lateral ventricles with an incidence of 47.4% (9 of 19 lesions, 7 in 11 patients). Patients with supratentorial tumors developed cystic malacia statistically earlier than the patients with infratentorial tumors (P = 0.0178, log-rank test). Among the same patient group, incidence of post-irradiation cavernous angioma increased progressively, while the incidence of post-irradiation cystic malacia did not increase after 5 years. White matter degeneration developed earlier than cystic malacia or cavernous angioma, and these three clinical entities developed mutually exclusive of each other. CONCLUSION: We attribute the higher incidence of post-irradiation cystic malacia, in our long-term follow-up study, to the cranial irradiation for pediatric brain tumors, particularly supratentorial brain tumors, and recommend a regular, long-term follow-up of brain tumor patients treated with cranial irradiation.

Benign fibrous histiocytoma arising at the temporal bone of an infant--case report and review of the literature.

PURPOSE: We report a very rare case of a fast-growing benign fibrous histiocytoma at the temporal bone. METHODS: A 1-year-old girl was referred for investigation of a right temporal mass that increased during 2-week observation. Imaging studies showed a lytic, loculated skull tumor at the left temporal bone. On magnetic resonance imaging scans, the tumor was isointense on T1- and relatively high-intense on T2-weighted images. The tumor was mostly homogeneously enhanced by gadolinium. On diffusion-weighted images, it was iso- to relatively low-intense; perfusion-weighted images revealed low perfusion. RESULTS: Complete macroscopic resection of the tumor was performed. Immunohistochemical analysis showed that the tumor was positive for CD68 and α-smooth muscle actin and negative for CD1a and CD34; the MIB-1 labeling index was 4 %. A diagnosis of primary benign fibrous histiocytoma of the skull was made. At 6-month follow-up, there were no clinical or radiological signs of tumor recurrence and/or metastasis. CONCLUSIONS: We review the clinical, radiological, and immunohistochemical characteristics of benign fibrous histiocytoma at the skull.

Cavernous angioma after chemotherapy for desmoplastic/nodular medulloblastoma associated with anhidrotic ectodermal dysplasia.

PURPOSE: While cavernous angioma (CVA) after cranial irradiation has been documented, its development after high-dose chemotherapy with autologous peripheral blood stem cell transplantation (PBSCT) has not. We present a patient with desmoplastic/nodular medulloblastoma (DNMB) associated with anhidrotic ectodermal dysplasia (AED) who developed CVA 2 years after high-dose chemotherapy and PBSCT. METHODS: A 1-year-old boy with ingravescent vomiting was admitted to our institute. He presented with a large head, a depressed nasal bridge, low-set ears, thick lips with peg-shaped teeth, hypohidrosis, sparse hair, thin atrophic skin, scaly dermatitis with frontal bossing, and a bulging anterior fontanel. Neuroradiological examination revealed multiple cerebellar masses with heterogeneous enhancement and speckled calcifications and severe obstructive hydrocephalus. The histological diagnosis of surgical specimens was DNMB, and he underwent postoperative multiple-drug chemotherapy with autologous PBSCT. The outcome was favorable and he did not undergo radiotherapy. RESULTS: After 2 years, intracranial hemorrhage was detected at his regular radiological check-up and he again underwent surgery. The histological diagnosis was CVA. CONCLUSIONS: To our knowledge, this is the first report of AED-associated DNMB and CVA.

p16 Gene Transfer Induces Centrosome Amplification and Abnormal Nucleation Associated with Survivin Downregulation in Glioma Cells.

OBJECTIVE: In human glioma cells, p16 gene transfer induced G1/S arrest, increased radiosensitivity and abnormal nucleation (especially bi- and multinucleation). Survivin suppression caused G2/M arrest, radiosensitization and an increase in aneuploidy accompanied by centrosome amplification. Abnormal nucleation and aneuploidy represent chromosome instability (CIN), and it is well known that centrosome amplification leads to CIN. However, little has been reported that suggests that transferring p16 causes centrosome overduplication during the G1/S phase. METHODS: The p16 gene was transferred into p16-null human glioma cell lines (U251MG and D54MG) using adenovirus with or without irradiation. Centrosome amplification was evaluated by immunofluorescence. We also investigated the DNA replication licensing factor CDT1, its inhibitor geminin and survivin expression as regulators of chromosomal segregation. RESULTS: p16 gene transfer with radiation initiated the greatest degree of centrosome overduplication. CDT1 showed low levels, geminin was unchanged and survivin decreased in Ax-hp16-infected cells with radiation. Those changes of factors affecting DNA licensing or chromosomal segregation might contribute to CIN. CONCLUSION: p16 transfer caused centrosome amplification even in G1/S phase-arrested cells. This suggests that p16 is involved in abnormal nucleation and radiosensitization in human glioma cells. © 2015 S. Karger AG, Basel.

The postirradiation incidence of cavernous angioma is higher in patients with childhood pineoblastoma or primitive neuroectodermal tumors than medulloblastoma.

PURPOSE: The purpose of this study is to investigate the incidence of cavernous angioma (CVA) in long-term survivors of childhood embryonal tumors treated by cranial irradiation. MATERIALS AND METHODS: Between 1990 and 2012, we treated 25 patients (13 males, 12 females) with embryonal tumors (17 medulloblastomas, 5 primitive neuroectodermal tumors (PNET), 3 pineoblastomas) with craniospinal irradiation. Follow-up ranged from 15.5 to 289.9 months, the irradiation dose to the whole neural axis from 18 to 36 Gy, and the total local dose from 49.6 to 60 Gy. All patients underwent follow-up magnetic resonance imaging (MRI) studies at least once a year, and the diagnosis of posttreatment CVA was based solely on MRI findings. RESULTS: At the time of this writing, 18 were alive and free of the recurrence of the original disease or the development of secondary neoplasms other than CVA; another 2 were alive with medulloblastoma or diffuse astrocytoma. Posttreatment, 14 patients developed CVAs in the course of a median of 56.7 months; 13 of these presented with multiple CVAs. Patients who underwent radiation therapy (RT) at an age younger than 6 years developed multiple CVAs significantly earlier than those treated at a later age (p = 0.0110). Patients with PNET or pineoblastoma developed Zabramski type 1 and 2 CVA significantly earlier than did medulloblastoma patients (p = 0.0042). CONCLUSION: We attribute the high rate of post-RT CVA in our long-term follow-up study of pediatric patients to the delivery of cranial irradiation for embryonal tumors, especially PNET and pineoblastoma, and recommend the regular, long-term follow-up of patients whose embryonal tumors were treated by cranial irradiation.