Ventriculopleural shunt outcomes for pediatric hydrocephalus: a single-institution experience

PURPOSE

The aim of this study is to analyze rates of ventriculopleural (VPL) shunt failure and complications among patients with pediatric hydrocephalus, and to analyze which factors may predict early (< 1 year) or late (> 1 year) VPL shunt failure in this sample.

METHODS

A retrospective chart review was conducted of all consecutive VPL shunt placements from 2000 to 2019 at our institution. Data was collected on patient characteristics, shunt history, and shunt type. Primary endpoints include rates of VPL shunt survival and rates of symptomatic pleural effusion. The Kaplan-Meier method was used to calculate shunt survival, and Fisher's exact test and t-test were used to compare differences between categorical variables and means, respectively (p < 0.05).

RESULTS

Thirty-one patients with pediatric hydrocephalus underwent VPL shunt placement (mean age 14.2 years). Of the 27 patients with long-term follow-up (mean 46 months), VPL shunt revision was required in 19, seven of which were due to pleural effusion. Overall shunt survival rates at 1, 3, 5, and 7 years were 76%, 62%, 55%, and 46%, respectively. Mean duration of shunt survival was 26.74 months. Overall pleural effusion rate was 26%. No patient-specific factors, including shunt valve type, were significantly associated with shunt survival, risk of early revision, or risk of pleural effusion.

CONCLUSIONS

Our results are comparable to those reported in the literature and represent one of the largest case series on the topic. VPL shunts are a viable second-line option when ventriculoperitoneal (VP) shunt placement is not possible or desirable, though there are high rates of shunt revision and pleural effusion.

Global Reduction of H3K4me3 Improves Chemotherapeutic Efficacy for Pediatric Ependymomas

BACKGROUND

Ependymomas (EPNs) are the third most common brain tumor in children. These tumors are resistant to available chemotherapeutic treatments, therefore new effective targeted therapeutics must be identified. Increasing evidence shows epigenetic alterations including histone posttranslational modifications (PTMs), are associated with malignancy, chemotherapeutic resistance and prognosis for pediatric EPNs. In this study we examined histone PTMs in EPNs and identified potential targets to improve chemotherapeutic efficacy.

METHODS

Global histone H3 lysine 4 trimethylation (H3K4me3) levels were detected in pediatric EPN tumor samples with immunohistochemistry and immunoblots. Candidate genes conferring therapeutic resistance were profiled in pediatric EPN tumor samples with micro-array. Promoter H3K4me3 was examined for two candidate genes, CCND1 and ERBB2, with chromatin-immunoprecipitation coupled with real-time PCR (ChIP-PCR). These methods and MTS assay were used to verify a relationship between H3K4me3 levels and CCND1 and ERBB2, and to investigate cell viability in response to chemotherapeutic drugs in primary cultured pediatric EPN cells.

RESULTS

H3K4me3 levels positively correlate with WHO grade malignancy in pediatric EPNs and are associated with progression free survival in patients with posterior fossa group A EPNs (PF-EPN-A). Reduction of H3K4me3 by silencing its methyltransferase SETD1A, in primary cultured EPN cells increased cell response to chemotherapy.

CONCLUSIONS

Our results support the development of a novel treatment that targets H3K4me3 to increase chemotherapeutic efficacy in pediatric PF-EPN-A tumors.

Polo-Like Kinase 4 (PLK4) Is Overexpressed in Central Nervous System Neuroblastoma (CNS-NB)

Neuroblastoma (NB) is the most common extracranial solid tumor in pediatrics, with rare occurrences of primary and metastatic tumors in the central nervous system (CNS). We previously reported the overexpression of the polo-like kinase 4 (PLK4) in embryonal brain tumors. PLK4 has also been found to be overexpressed in a variety of peripheral adult tumors and recently in peripheral NB. Here, we investigated PLK4 expression in NBs of the CNS (CNS-NB) and validated our findings by performing a multi-platform transcriptomic meta-analysis using publicly available data. We evaluated the PLK4 expression by quantitative real-time PCR (qRT-PCR) on the CNS-NB samples and compared the relative expression levels among other embryonal and non-embryonal brain tumors. The relative PLK4 expression levels of the NB samples were found to be significantly higher than the non-embryonal brain tumors (p-value < 0.0001 in both our samples and in public databases). Here, we expand upon our previous work that detected PLK4 overexpression in pediatric embryonal tumors to include CNS-NB. As we previously reported, inhibiting PLK4 in embryonal tumors led to decreased tumor cell proliferation, survival, invasion and migration in vitro and tumor growth in vivo, and therefore PLK4 may be a potential new therapeutic approach to CNS-NB.

Chiari type I malformation of infants and toddlers

OBJECTIVES

Chiari I malformation has been a well-recognized clinical entity; however, its occurrence among infants and toddlers is unusual. Their clinical presentations may be different from other age groups due to their lack of effective verbal communication. The authors analyze their personal series of patients focusing on symptomatology and MRI characteristics. Treatment methods, results, and outcome are analyzed in order to identify appropriate surgical management among infants and toddlers with Chiari I malformation.

METHODS

The authors retrospectively reviewed 16 patients who were diagnosed and surgically treated between 2007 and 2014 during the first 3 years of life with minimum follow-up of 3 years. We focused on the presenting symptoms, magnetic resonance imaging findings, and surgical techniques used for posterior fossa decompression (PFD) and their postoperative outcome.

RESULTS

Twelve patients (75%) presented with signs of headaches such as irritability, inconsolable crying, head grabbing, and/or arching back. Ten patients (62.5%) presented with oropharyngeal and/or respiratory symptoms such as emesis, choking, gagging, snoring, sleep apnea, breathing pause, and/or vocal cord palsy. Only one patient had segmental cervical hydromyelia. At the first surgery, ten patients had PFD with dural scoring (Type 1 procedure), while six others had PFD with duraplasty (Type 2 procedure) with thermal reduction of the cerebellar tonsils in four. Following the first operation, all initially had varying degrees of symptomatic improvement; however, seven patients subsequently had symptomatic recurrence. Persistent crowding at the PFD site on the postoperative imaging indicated greater risk of recurrences in both Type 1 procedure and Type 2 procedure groups. Of seven patients who needed a second operation, fivewere after Type 1 procedure and the two were after Type 2 procedure. The difference of recurrence rates between these two groups is not significant. CSF-related complications occurred in 4 out of 11 patients who had Type 2 procedure (one after primary decompression and three after the second decompression for recurrence).

CONCLUSION

Young patients lacking effective verbal communication often present their Chiari I malformation differently from olderage groups. Behavioral changes indicative of headaches/irritability and oropharyngeal/respiratory symptoms are the primary presenting symptoms. The recurrence rate tends to be higher among the patients after Type 1 procedure (particularly those younger than 18 months) than after Type 2 procedure. We observed that duraplasty at primary or at redo PFD provides for better decompression and long-term outcome. However, one should keep it in mind that there is risk of CSF-related complications following duraplasty, particularly higher tendency after redo PFD.

Targeting CD133 improves chemotherapeutic efficacy of recurrent pediatric pilocytic astrocytoma following prolonged chemotherapy

Background

Pilocytic astrocytomas (PAs) are the most common pediatric central nervous system neoplasms. In the majority of cases these tumors are benign and receive favorable prognosis following gross total surgical resection. In patients with progressive or symptomatic tumors, aggressive surgical resection is generally not feasible, thus radiation or chemotherapy are accepted initial or adjuvant interventions. Due to serious long-lasting side-effects, radiation is limited in young children; therefore, chemotherapy is widely practiced as an adjuvant treatment for these patients. However, chemotherapy can promote the emergence of multidrug resistant tumor cells that are more malignant than those of the original tumor. CD133, a putative stem cell marker in normal tissue and malignant brain tumors, enhances multidrug resistant gene 1 (MDR1) expression following chemotherapy in adult malignant glioblastomas. This study examines the relationship between CD133 and MDR1 in pediatric PAs exposed to chemotherapy, with the goal of identifying therapeutic targets that manifest as a result of chemotherapy.

Methods

Slides were obtained for 15 recurrent PAs, seven of which had received chemotherapy prior to surgical treatment for the recurrent tumor. These samples, as well as primary tumor tissue slides from the same patients were used to investigate CD133 and MDR1 expression via immunofluorescence. Archived frozen tissue samples from the same patients were used to examine CD133, MDR1 and PI3K-Akt-NF-κB signaling mediators, via western blot. Two drug resistant pediatric PA cell lines Res186 and Res199 were also used to evaluate the role of CD133 on cell response to cytotoxic therapy.

Results

CD133 and MDR1 were co-expressed and their expression was elevated in recurrent PAs from patients that had received chemotherapy, compared to patients that had not received chemotherapy. PI3K-Akt-NF-κB signaling mediator expression was also elevated in recurrent, chemotherapy-treated PA. Suppressing CD133 expression with siCD133 decreased levels of PI3K-Akt-NF-κB signaling mediators and MDR1, while increasing cell chemosensitivity, as indicated by quantification of apoptotic cells following chemotherapy.

Conclusions

CD133 contributes to multidrug resistance by regulating MDR1 levels via the PI3K-Akt-NF-κB signal pathway not only in adult glioblastomas, but also in pediatric PAs. Targeting CD133, adjuvant to conventional chemotherapy may improve outcomes for children with recurrent PA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-017-0593-z) contains supplementary material, which is available to authorized users.