Brain tumors of infancy--an institutional experience and review of the literature

The Role of Early and Delayed Surgery for Infants with Congenital Brain Tumors

PURPOSE

The present study aimed to evaluate the role of early and delayed surgery in congenital brain tumors and analyze the clinical outcomes of infantile brain tumors.

MATERIALS AND METHODS

We performed a retrospective cohort study on 69 infantile brain tumors at a single institution from January 2008 to June 2023. Outcomes were assessed as early mortality (within 30 days following surgery) to evaluate the risk of early surgery in congenital brain tumors. Outcomes of recurrence and overall survival were analyzed in infantile brain tumors.

RESULTS

Surgery-related early mortality appeared to occur in young and low-body-weight patients. Cut-off values of age and body weight were found to be 1.3 months and 5.2 kg to avoid early mortality. Three patients (3/10, 30%) showed early mortality in the early surgery group, and early mortality occurred in one patient (1/14, 7.14%) in the delayed surgery group, whose tumor was excessively enlarged. Younger age at diagnosis (< 3 months of age; hazard ratios [HR], 7.1; 95% confidence intervals [CI], 1.4 to 35.6; p=0.018) and leptomeningeal seeding (LMS; HR, 30.6; 95% CI, 3.7 to 253.1; p=0.002) were significant independent risk factors for high mortality in infantile brain tumors.

CONCLUSION

We suggest delaying surgery until the patient reaches 1.3 months of age and weighs over 5.2 kg with short-term imaging follow-up unless tumors grow rapidly in congenital brain tumors. Younger ages and the presence of LMS are independent risk factors for high mortality in infantile brain tumors.

Prognostic value of Ki-67 index in primary intracranial tumors of infants

OBJECTIVE

Primary intracranial tumors are rare tumors in infants. They differ from those found in other pediatric age groups in terms of clinical presentation, histopathological diagnosis, adjuvant therapies, and outcome. Ki-67 index has also shown promising results as a prognostic factor in different types of intracranial tumors in children and adults. However, the importance and the best cutoff point of Ki-67 index in primary intracranial tumors of infants remains unclear. We aimed to analyze prognostic value of Ki-67 index in primary intracranial tumors of infants.

METHODS

This study retrospectively reviewed the records of 28 infants undergoing surgical resection for primary intracranial tumors between April 2016 and March 2021. We analyzed clinical characteristics, tumor location, extent of resection, histopathological diagnosis, Ki-67 index, and overall survival (OS). To define the most relevant cutoff value for Ki-67 index, "Cutoff Finder" was used.

RESULTS

The median age at diagnosis was 188 days for all patients. Fifteen of the patients were boys and 13 were girls. Tumors were located supratentorial in 13 patients and infratentorial in 15 patients. Gross total resection was performed in 7 of 13 supratentorial tumors and 9 of 15 infratentorial tumors. The mean Ki-67 index of the supratentorial tumors was 49.6%, the median was 55%; for infratentorial tumors, the mean was 49.9%, and the median was 70%. Tumor grade (p = 0.019) and Ki-67 index (p = 0.003) were found as significant predictors of OS in log-rank testing for Kaplan-Meier survival analysis. Univariate cox regression analysis identified high Ki-67 index as prognostic factor for worse OS, with hazard ratio of 8.852 (95% CI 1.95-64.80; p = 0.0108). High Ki-67 index was found as independent prognostic factor for worse OS in multivariate cox regression analysis (HR 7.036; 95% CI 1.229-65.82; p = 0.0457).

CONCLUSION

High-grade and high Ki-67 index were associated with worse outcome. Ki-67 index did show a distinct prognostic value for OS within our cohort at a cutoff value of 72.5%.

Brain tumors in the first two years of life

Background

Brain tumors in the first years of life are frequently encountered recently with the advancement in neuroimaging, neurosurgery and neuroanethesia where early diagnosis of these lesions became available even before birth. Their management is challenging where the surgery is technically demanding, radiotherapy is omitted in this age because of its late sequelae and chemotherapy role may be beneficial, but it is limited also by its side effects and neurotoxicity. The aim of this article is to review the current literature about the brain tumors in the first two years of life, their diagnosis and treatment.

Main body

Brain tumors in the first two years of life encompass mainly fetal/congenital tumors and infantile tumors. They account for 1.4–18% of cases of pediatric brain tumor, and most of them are diagnosed in the first year of life. The main histopathologies diagnosed are glial tumors, choroid plexus tumors, medulloblastoma and other embryonal tumors, teratoma and ependymoma. They are mainly supratentorial. Large head and bulging fontanelles are the main presenting symptoms and signs secondary to increased intracranial pressure secondary to large tumors or associated hydrocephalus. Prenatal and postnatal ultrasonography represents the initial imaging step in the diagnosis that should be complemented by MRI and CT brain. The main and first line of treatment of infantile brain tumors is surgical excision as the prognosis is directly related to the extent of resection besides surgery offers specimens for histopathological diagnosis and adjuvant chemotherapy is given for residual irresectable cases and malignant tumors with the main aim to delay radiotherapy beyond the age of three years.

Conclusion

Brain tumors in the first two years of life are a challenging group of different histopathological entities with underlying specific molecular characterization and genetic predispositions. They have aggressive behavior and general poor prognosis with limited options of management. Individualized multidisciplinary management for each case is needed, and future studies for therapeutic medications targeting underlying molecular biology may improve their outcome.

Tumor-related hydrocephalus in infants: a narrative review

Primary brain tumors diagnosed during infancy present several challenges for the pediatric neurosurgeon including the management of tumor-related hydrocephalus. Infant tumor-related hydrocephalus (iTRH) is present in over 70% of new diagnoses overall and in over 90% of infants with infratentorial neoplasms. iTRH may be related to direct obstruction of cerebrospinal fluid (CSF) pathways, shedding of protein and/or cells leading to dysfunctional subarachnoid, tumor-related CSF production, or, most frequently, a combination of these mechanisms. Treatment plans must consider the acuity of presentation, the mechanism of iTRH, and the additional neoadjuvant or adjuvant therapies required to treat the neoplasm. This narrative review provides a broad reference on the epidemiology, pathophysiology, and treatment of iTRH.

Perioperative Factors Affecting Neurologic Outcome in Infants Undergoing Surgery for Intracranial Lesion: A Retrospective Study

BACKGROUND

The short-term neurologic outcome of infants undergoing brain tumor surgery depends on various perioperative factors. This study was undertaken to analyze the effects of perioperative variables on the postoperative neurologic outcome in infants undergoing brain tumor surgery.

METHODS

We retrospectively reviewed the chart of infants undergoing craniotomy for brain tumor removal from 2000 to 2017. The data related to preoperative variables, intraoperative management details, and postoperative factors were collected and analyzed. The primary outcome measure was occurrence of new postoperative neurologic deficit (POND) and the secondary outcome measure was length of hospital stay (LOHS).

RESULTS

Complete data were available for 40 infants undergoing craniotomy for excision of intracranial tumor. New-onset POND was found in 14 infants (35%). Based on logistic regression analysis, POND was associated with use of mannitol and massive blood transfusion (MBT) trended toward significance. Based on linear regression analysis, the risk factor associated with prolonged LOHS was reintubation and POND trended toward significance.

CONCLUSIONS

In this study, factors associated with new POND were mannitol use and to a certain extent MBT. The variables associated with prolonged LOHS were reintubation and to a certain extent POND. The anesthetic technique, location of tumor, tumor histology, and extent of tumor resection did not influence the occurrence of new POND or prolonged LOHS in infantile intracranial tumor surgery. Further prospective studies with larger samples are required for confirmation of these findings and identification of new perioperative risk factors.

The magnitude and predictors of therapy abandonment in pediatric central nervous system tumors in low- and middle-income countries: Systematic review and meta-analysis

BACKGROUND

Outcomes of pediatric central nervous system (CNS) tumors in low- to middle-income countries (LMIC) are poorer than their high-income counterparts. Abandonment of therapy is increasingly recognized as a key contributor to this disparity, but has been poorly quantified. We performed a meta-analysis to determine the magnitude of abandonment in pediatric CNS tumors in LMIC, and risk factors and interventions aimed at reducing this.

PATIENTS AND METHODS

We searched seven databases for pediatric CNS tumor cohorts followed up from diagnosis and treated in LMIC. All languages were included. Two reviewers independently selected articles and extracted data on abandonment rates (ARs) and predictors. The authors were contacted for additional information.

RESULTS

Of 50 660 publications, 643 in five languages met criteria for full review; 131 met analysis inclusion criteria. ARs were not reported in the majority, and a small number were available from the authors. Available ARs ranged from 0% to 59%, from 38 studies (2497 children in 14 countries), and these were quantitatively analyzed. Lower-middle-income countries had higher ARs than upper-middle-income countries (27%, 95% confidence interval [CI] 20%-36% vs 9%, 95% CI 6%-14%, P < 0.0001), with significant heterogeneity within each (LMIC I₂  = 78%, P < 0.00001, UMIC I₂  = 85%, P < 0.00001). Common predictors for abandonment included distance to treatment centers, financial hardship, and prognostic misconceptions.

CONCLUSION

In LMICs, ARs are highest in lower-MICs. However, the paucity of published data limits further evaluation. Given the increasing burden of pediatric CNS tumors in LMIC, addressing deficits in abandonment reporting is critical. Consistent reporting is needed for developing interventions to improve outcomes.

Feasibility of high-dose chemotherapy protocols to treat infants with malignant central nervous system tumors: Experience from a middle-income country

BACKGROUND

Results of high-dose chemotherapy (HDCT) protocols for the management of malignant central nervous system (CNS) tumors in infants are mostly reported in high-income countries. We evaluated the feasibility and results of such protocols in a middle-income country (Jordan).

METHODS

A retrospective study of infants' charts with CNS tumors between 2006 and 2015 who were treated according to HeadStart (HS) protocols. Data included patients' demographics, chemotherapy complications, and cost.

RESULTS

We identified 18 patients with median age 29 months (range, 9-62 months) at diagnosis (12 HS-I and six HS-II). Distribution according to pathology was: atypical teratoid rhabdoid tumors (ATRT) (nine), primitive neuoroectodermal tumors (PNET)/pineoblastoma (five), and medulloblastoma (four). Six patients (33%) had metastatic disease, and 14 (78%) had an incomplete resection. Eleven patients achieved partial or complete remission, two stabilized, and five progressed. Ten patients did not proceed to HDCT due to progression (five), financial reasons (two), failure to collect stem cells (one), and undocumented reasons (two). Seventy-eight chemotherapy cycles were administered (median interval 26 days). Main complications during induction and consolidation were febrile neutropenia (73% and 100%), documented infections (8% and 13%), and mucositis (12% and 88%), respectively. Three patients developed moderate hearing loss. No protocol-related mortality was reported. At the last follow-up, five patients were alive: three with medulloblastoma (19, 29, and 89 months) and two with ATRT (18 and 42 months). Three survivors received focal/craniospinal radiation. The median cost of a complete HS protocol, excluding surgery/radiotherapy, was $103 500 per patient; 39% of the median cost was related to pharmacy expenses.

CONCLUSIONS

These protocols were manageable in our context of limited health care resources. However, considering the significant costs and the modest survival rate, better selection criteria need to be used to identify patients likely to benefit from this approach.

Pediatric Intracranial Tumors over a 5-Year Period in a Tertiary Care Center of North Kerala, India: A Retrospective Analysis

Background:

Pediatric brain tumors are unique in terms of distribution, clinical presentation, pathologic types, management, and prognosis. There are not many studies from India which have looked into the epidemiology of pediatric brain tumors.

Aims:

This study aimed to analyze the epidemiology of pediatric brain tumors in North Kerala and compare it with data from the rest of India and other countries.

Materials and Methods:

This is a retrospective study of 5-year data of pediatric brain tumors which were operated in a tertiary referral center in North Kerala, India, from 2009 to 2013. The data were procured from the departments of neurosurgery and pathology of the institution. The data were tabulated and analyzed using SPSS software.

Results:

A total of 71 children had histologically proven brain tumors during the 5-year period. There were 34 boys and 37 girls. Distribution in different age groups was as follows: infancy –5 (7%), 1–5 years –22 (31%), 6–10 years – 21 (29.6%), and 11–18 years – 23 (32.4%). The most common tumors were primitive neuroectodermal tumors (PNETs). In infancy, the number of high-grade tumors was more, whereas in the 11–18 years’ age group, there were a significantly higher number of low-grade tumors (P = 0.04).

Discussion:

Pediatric brain tumors were distributed almost equally in both sexes. PNET was the most common. We could not get statistical significance in many of our values due to small sample size.

Conclusion:

This study highlights the need for diligent collection of data and maintenance of a registry for brain tumors to study the disease in the Indian population.

Ganglioglioma, Epilepsy, and Intellectual Impairment due to Familial TSC1 Deletion

BACKGROUND

Tuberous sclerosis complex (TSC) is a multisystem disorder diagnosed by clinical criteria and/or genetic testing. Genetic testing reveals atypical phenotypes that have not met clinical criteria, with practical implications.

METHODS

We describe 4 family members with pathogenic partial deletion in TSC1 who individually did not meet tuberous sclerosis complex clinical criteria.

RESULTS

Family members had different and atypical findings of tuberous sclerosis complex. Although none of the family members fulfilled the clinical criteria for tuberous sclerosis complex, they all carried the same genomic deletion (9q34.13q34.2) that included part of the TSC1 gene. One member had ganglioglioma and intractable seizures, one sibling presented with seizures, developmental delay, and displayed white matter abnormalities; another sibling had no clinical manifestations but has cortical tuber. Their mother has facial angiofibroma, cortical tuber, and seizures during infancy.

CONCLUSIONS

Ganglioglioma may be a phenotypic expression of TSC1. Genetic testing is recommended for infants with brain tumors, especially those with an abnormal familial history.

Brain tumors in infants

Background:

Brain tumors in infants have different clinical presentations, anatomical distribution, histopathological diagnosis, and clinical prognosis compared with older children.

Materials and Methods:

A retrospective analysis was done in patients <12 months old who were operated on for primary brain tumor in Children's Hospital Medical Center since 2008 to 2014.

Results:

Thirty-one infants, 20 males and 11 females, with the mean age of 7.13 months (0.5–12) were enrolled. There were 16 supratentorial and 15 infratentorial tumors. The presenting symptoms included increased head circumference (16); bulge fontanel (15); vomiting (15); developmental regression (11); sunset eye (7); seizure (4); loss of consciousness (4); irritability (3); nystagmus (2); visual loss (2); hemiparesis (2); torticollis (2); VI palsy (3); VII, IX, X nerve palsy (each 2); and ptosis (1). Gross total and subtotal resection were performed in 19 and 11 cases, respectively. Fourteen patients needed external ventricular drainage in the perioperative period, from whom four infants required a ventriculoperitoneal shunt. One patient underwent ventriculoperitoneal shunting without tumor resection. The most common histological diagnoses were primitive neuroectodermal tumor (7), followed by anaplastic ependymoma (6) and grade II ependymoma. The rate of 30-day mortality was 19.3%. Eighteen patients are now well-controlled with or without adjuvant therapy (overall survival; 58%), from whom 13 cases are tumor free (disease free survival; 41.9%), 3 cases have residual masses with fixed or decreased size (progression-free survival; 9.6%), and 2 cases are still on chemotherapy.

Conclusion:

Brain tumors in infants should be treated with surgical resection, followed by chemotherapy when necessary.

EGF as a New Therapeutic Target for Medulloblastoma Metastasis

Medulloblastoma (MB) is a malignant pediatric brain tumor known for its aggressive metastatic potential. Despite the well-documented migration of MB cells to other parts of the brain and spinal column, MB chemotaxis is poorly understood. Herein, we examined the in vitro migratory and cellular responses of MB-derived cells to external signaling of Epidermal Growth Factor (EGF), hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF-BB), and the stromal cell-derived factors 1-alpha (SDF-1). Experiments utilized transwell assays and immunocytochemistry to identify receptor activation in MB migration, and used a microfluidic platform to examine directionality, trajectory, and gradient-dependence of motile cells. Data illustrates that MB-derived cells respond strongly to EGF in a dosage and gradient-dependent manner with increased EGF-R activation, and show that high EGF gradient fields cause an increased number of cells to migrate longer directed distances. Our results provide evidence that EGF and its receptor play an important role than previously documented in MB chemotactic migration than previously documented and should be considered for developing migration-target therapies against MB metastasis.