Survival and Prognostic Factors in Pediatric Patients with Medulloblastoma in Southern Thailand

Clinical, Histological, and Molecular Prognostic Factors in Childhood Medulloblastoma: Where Do We Stand?

Medulloblastomas, highly aggressive neoplasms of the central nervous system (CNS) that present significant heterogeneity in clinical presentation, disease course, and treatment outcomes, are common in childhood. Moreover, patients who survive may be diagnosed with subsequent malignancies during their life or could develop treatment-related medical conditions. Genetic and transcriptomic studies have classified MBs into four subgroups: wingless type (WNT), Sonic Hedgehog (SHH), Group 3, and Group 4, with distinct histological and molecular profiles. However, recent molecular findings resulted in the WHO updating their guidelines and stratifying medulloblastomas into further molecular subgroups, changing the clinical stratification and treatment management. In this review, we discuss most of the histological, clinical, and molecular prognostic factors, as well the feasibility of their application, for better characterization, prognostication, and treatment of medulloblastomas.

Postoperative radiotherapy timing, molecular subgroups and treatment outcomes of Thai pediatric patients with medulloblastoma

INTRODUCTION

Medulloblastoma (MB) is the most common childhood malignant brain tumor worldwide. Recently, molecular classification was established and started to play a role in the management of MB; however, studies involving molecular defined MB in Southeast Asia have been limited. We aimed to describe, and correlate clinical characteristics and molecular subgroups with therapeutic outcomes of Thai pediatric patients with MB.

MATERIALS AND METHODS

Pediatric MB patients treated at King Chulalongkorn Memorial Hospital in Thailand from 2006 to 2018 were recruited. Patients were classified by clinical characteristics into standard- and high-risk groups, which determined treatment regimen. Retrospectively, available tumor tissues were classified into 3 molecular subgroups using immunohistochemistry: 1) WNT, 2) SHH, and 3) non-WNT/non-SHH. The primary outcome was 5-year overall survival (OS). Risk factors associated with OS were analyzed using cox regression analysis.

RESULTS

Fifty-three Thai pediatric patients with MB were enrolled. The median follow-up time was 60 months. The 5-year OS for all patients, and patients with standard-risk and high-risk were 74.2%, 76.3% and 71.4%, respectively. Tumor tissues of 24 patients were available, of which 23 could be molecularly classified. Two, one and 20 were in the WNT, SHH and non-WNT/non-SHH subtypes with 5-year OS of 100%, 100% and 78.9%, respectively. Using multivariate analysis, the interval of more than 8 weeks between surgery and radiotherapy was significantly correlated with a decrease in the 5-year OS.

CONCLUSION

Interval between surgery and radiotherapy within 8 weeks was associated with good therapeutic outcomes among Thai pediatric patients with MB. Simplified molecular subtyping combined with clinical characteristics is practical in risk classification of patients with MB in institutes with limited resources.

Optimization of Tokuhashi Scoring System to Improve Survival Prediction in Patients with Spinal Metastases

Introduction: Predicting survival time for patients with spinal metastases is important in treatment choice. Generally speaking, six months is a landmark cutoff point. Revised Tokuhashi score (RTS), the most widely used scoring system, lost its accuracy in predicting 6-month survival, gradually. Therefore, a more precise scoring system is urgently needed. Objective: The aim of this study is to create a new scoring system with a higher accuracy in predicting 6-month survival based on the previously used RTS. Methods: Data of 171 patients were examined to determine factors that affect prognosis (reference group), and the remaining (validation group) were examined to validate the reliability of a new score, adjusted Tokuhashi score (ATS). We compared their discriminatory abilities of the prediction models using area under receiver operating characteristic curve (AUC). Results: Target therapy and the Z score of BMI (Z-BMI), which adjusted to the patients’ sex and age, were additional independent prognostic factors. Patients with target therapy use are awarded 4 points. The Z score of BMI could be added directly to yield ATS. The AUCs were 0.760 for ATS and 0.636 for RTS in the validation group. Conclusion: Appropriate target therapy use can prolong patients’ survival. Z-BMI which might reflect nutritional status is another important influencing factor. With the optimization, surgeons could choose a more individualized treatment for patients.

Survival Study in Pediatric Patients with Medulloblastoma in a General Hospital in Tehran, Iran

Brain tumours are the most common solid tumours that afflict the pediatric population. Me-dulloblastoma (MB) is the most common malignant brain tumour in children, constituting nearly 20% of all pediatric brain tumours. This study is an evaluation of overall survival rate of pediatric MB tumour patients after one year, three years, five years, and ten years according to case studies. From 22 June 2009 to 19 December 2019, a total of 22 patients ranging in age from 1 to 14 years old underwent tumour removal. These patients were followed to determine survival rate. Tumours were classified into three pathological subtypes: The first was classic MB, the second was desmoplastic nodular MB and MB with extensive nodularity, and the third was large cell and anaplastic MB. Patients who were 3 years old or older had a better survival rate than younger patients (log-rank test; p = 0.01). The survival probability in the older children group (55%) was significant compared to the group of younger children (29%). The Kaplan–Meier survival curves of the patients were significantly different. The ten-year survival rates in the average- and high-risk groups were 64.4% and 86.0%, respectively. After a follow-up of 120 months (median range = 60 months), recurrence or progression was observed in 22 patients and 15 patients were still alive. The estimated 10-year overall survival rates for all patients were 49.36 ± 38.33. MB patients’ survival rate was quite good in our hospital. More than half of the patients, most of whom had large cell anaplastic and classic type MB, survived the 10-year follow-up period without any problems.

Pediatric Medulloblastoma: Prognostic Value of Preoperative Blood Cell Ratios

Background: The prognostic significance of preoperative neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR), and platelet to lymphocyte ratio (PLR) have been demonstrated in various tumors. This study aimed to evaluate the prognostic role of these ratios in pediatric medulloblastoma. Materials and Methods: Forty-three pediatric patients with medulloblastoma were evaluated, retrospectively. Clinical, radiological, and laboratory data were extracted from the electronic medical records of the patients. Univariate and multivariate Cox proportional hazard models were used to evaluate the impact of suggested variables, including NLR, LMR, and PLR on progression-free survival (PFS) and overall survival (OS). Kaplan-Meier curves were plotted for the assessment of PFS and OS. The Log-rank test was used to assess differences between the PFS and OS in the related categories.  Results: There were 27 males (62.8%) and 16 females (37.2%) with a mean age of 7.4 ±3.3 years. The median OS and PFS were 62.8 ±17.2 and 43.3 ±15.6 months, respectively. The multivariate Cox model showed the clinical risk group, NLR, and LMR as independent predictors of the PFS and the OS (p<0.05). The Log-rank test revealed that OS and PFS were higher in patients with NLR <4 and those with LMR ≥ 3.48 (p <0.05). There were no differences between patients with PLR>200 and PLR< 200 based on OS and PFS. Conclusion: Our results suggest an elevated preoperative NLR and a lowered preoperative LMR as simple predictors of survival in pediatric medulloblastoma. These cost-effective and easily available ratios, along with previously established variables, could be valuable to predict survival in pediatrics with medulloblastoma.

A Holistic Review on the Current and Future Status of Biology-Driven and Broad-Spectrum Therapeutic Options for Medulloblastoma

With a thorough investigation of the etiology of medulloblastomas, a comprehensive review was done to categorize available clinical trials in order to discuss the future potential of breakthroughs in treatment options. The pertinent issues of medulloblastoma therapy with radiation being inapplicable to children under the age of 3, and therapies causing toxicity are detailed and discussed in the context of understanding how the current therapies may address these suboptimal treatment modalities. This study aggregated published studies from the US government clinical trials website and filtered them based on their direct treatment towards medulloblastomas. Thirty-two clinical trials were applicable to be analyzed and the treatment mechanisms were discussed along with the efficacy; molecular groupings of medulloblastomas were also investigated. The investigated therapies tend to target sonic hedgehog (SHH)-subtype medulloblastomas, but there is a necessity for group 3 subtype and group 4 subtype to be targeted as well. Due to the heterogeneous nature of tumor relapse in groups 3 and 4, there are less specified trials towards those molecular groupings, and radiation seems to be the main scope of treatment. Medulloblastomas being primarily a pediatric tumor require treatment options that minimize radiation to increase the quality of living in children and to prevent long-term symptoms of over radiation. Exploring symptomatic treatment with donepezil in children with combination therapies may be a potential route for future trials; immunotherapies seem to hold potential in treating patients reacting adversely to radiation therapy.

Risk Factors for Survival in Patients With Medulloblastoma: A Systematic Review and Meta-Analysis

Background

Conventional parameters show limited and unreliable correlations with medulloblastoma prognosis.

Aim

To evaluate the factors influencing overall survival (OS), event-free survival (EFS), and progression-free survival (PFS) in patients with medulloblastoma.

Methods

PubMed, EMBASE, the Cochrane Library, and Web of Science were searched for studies published up to May 2021. The associations between various clinical and treatment factors and survival parameters were assessed.

Results

Twenty-nine studies (8455 patients) were included. Desmoplastic medulloblastoma (HR=0.41, 95%CI: 0.31-0.56), M0 disease (HR=2.07, 95%CI: 1.48-2.89), WNT, SSH, group 4 (all P<0.05 vs. group 3), GTR vs. STR (HR=1.37, 95%CI: 1.04-1.08), radiotherapy (HR=0.45, 95%CI: 0.20-0.80), craniospinal irradiation (HR=0.49, 95%CI: 0.38-0.64), and high 5hmC levels (HR=2.90, 95%CI: 1.85-4.55) were associated with a better OS. WNT, SSH, group 4 (all P<0.05 vs. group 3), residual tumor ≤1.5 cm2 (HR=2.08, 95%CI: 1.18-3.68), GTR vs. STR (HR=1.31, 95%CI: 1.03-1.68), craniospinal irradiation (HR=0.46, 95%CI: 0.37-0.57), high 5hmC levels (HR=3.10, 95%CI: 2.01-4.76), and <49 days between resection and radiotherapy (HR=2.54, 95%CI: 1.48-4.37) were associated with better PFS. Classic vs. desmoplastic medulloblastoma (HR=1.81, 95%CI: 1.04-3.16), SSH, WNT (both P<0.05 vs, non-SSH/non-WNT), GTR vs. STR (HR=2.01, 95%CI: 1.42-2.85), and radiotherapy (HR=0.31, 95%CI: 0.15-0.64) were associated with a better EFS.

Conclusion

Histology, molecular subgroup, GTR, and radiotherapy are significantly associated with survival parameters in patients with medulloblastoma. Nevertheless, high-quality prospective cohort studies are necessary to improve the conclusions.

Epidemiological characteristics and survival outcomes of children with medulloblastoma treated at the National Cancer Institute (INCA) in Rio de Janeiro, Brazil

BACKGROUND

Medulloblastoma (MB),the most common malignant brain tumor of childhood has survival outcomes exceeding 80% for standard-risk and 60% for high-risk patients in high-income countries (HICs). These results have not been replicated in low- and middle-income countries (LMICs), where 80% of children with cancer live.

METHODS

This is a retrospective review of 114 children aged 3-18 years diagnosed with MB from 1997 to 2016 at National Cancer Institute (INCA). Sociodemographic, clinical, and treatment data were extracted from the medical records and summarized descriptively. Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method.

RESULTS

The male-to-female ratio was 1.32 and the median age at diagnosis was 8.2 years. Headache (83%) and nausea/vomiting (78%) were the most common presenting symptoms. Five-year OS was 59.1% and PFS was 58.4%. The OS for standard-risk and high-risk patients was 69% and 53%, respectively. The median time to diagnosis interval was 50.5 days and the median time from surgery to radiation therapy initiation was 50.4 days. Patients who lived >40 km from INCA fared better (OS = 68.2% vs. 51.1%, p = .032). Almost 20% of families lived below the Brazilian minimum wage. Forty-five patients (35%) had metastatic disease at admission. Gross total resection was achieved in 57% of the patitents.

CONCLUSIONS

Although there are considerable barriers to deliver effective MB treatment in countries like Brazil, the OS seen in the present study demonstrates that good outcomes are not only feasible but can and should be increased with appropriate interventions.

Risk Factors Associated with Post-therapeutic Outcome for Medulloblastoma: An Experience from Indonesia

Context:

The prognosis of medulloblastoma is better in patients who underwent complete treatment consisting of surgery, radiotherapy, and chemotherapy. However, the realization of such multidiscipline management is quite challenging in developing countries, including Indonesia. Until now, no study on the management of medulloblastoma has ever been conducted in Indonesia.

Aims:

The authors aimed to study the characteristics, management, and mortality outcome of medulloblastoma patients in Dr. Cipto Mangunkusumo National Referral Hospital, Jakarta, Indonesia.

Subjects and Methods:

This study was based on medical record and registry of 44 medulloblastoma patients who underwent tumor removal in Dr. Cipto Mangunkusumo National Referral Hospital, Jakarta, Indonesia, between 2011 and 2018.

Statistical Analysis Used:

Cox regression analysis was utilized to determine the relationship between patients' demography, tumor characteristics, and treatment, with mortality.

Results:

The incidence of mortality was 84.1% and median months' survival time (95% confidence interval [CI]) was 13 (8.67–17.32). Gross total removal (GTR) was performed in 43.2% of all tumor removal surgery. Only 50% of all patients completed radiotherapy, and 6.8% concluded multimodalities treatment (surgery, radiotherapy, and chemotherapy). Significant statistical association between age, gender, and extent of resection with mortality was identified (HR [95% CI] for age: 0.44 [0.22–0.88], gender: 0.001 [0.000–0.27; REF: female], and biopsy: 31.52 [1.09–910.56; REF: GTR]).

Conclusions:

The survival rate of medulloblastoma in Indonesia is inferior to that previously reported in other studies. There is no unusual characteristic contributing to neoteric risk factor. The authors surmise that insufficient multidisciplinary management for the disease, consisting of suboptimal tumor resection, the absence of risk stratification, and incomplete postsurgical treatment (radiotherapy and chemotherapy) resulted in such outcome.

Peptide Receptor Radionuclide Therapy and Primary Brain Tumors: An Overview

Primary brain tumors (PBTs) are some of the most difficult types of cancer to treat, and despite advancements in surgery, chemotherapy and radiotherapy, new strategies for the treatment of PBTs are needed, especially for those with poor prognosis such as inoperable/difficult-to-reach lesions or relapsing disease. In regard to the last point, malignant primary brain tumors remain some of the most lethal types of cancer. Nuclear medicine may provide exciting new weapons and significant contributions in the treatment of PBTs. In this review, we performed literature research in order to highlight the possible role of peptide receptor radionuclide therapy (PRRT) in the treatment of PBTs with radiolabeled molecules that bind with high-affinity transmembrane receptors such as somatostatin receptors (SSTRs), neurokinin type-1 receptor and prostate-specific membrane antigen (PSMA). These receptors are overexpressed in some cancer types such as gliomas, meningiomas, pituitary tumors and medulloblastomas. A comprehensive overview of possible applications in this field will be shown, providing knowledge about benefits, feasibility, developments and limitations of PRRT in this type of tumor, also revealing new advantages in the management of the disease.

Simplified Molecular Subtyping of Medulloblastoma for Reduced Cost and Improved Turnaround Time

Molecular subtyping of medulloblastoma (MB) has become increasingly important for prognosis and management. Typically this involves detailed molecular genetic testing which may not be available in all centers. The purpose of the present study was to find a simplified approach to assign molecular subtypes of MB for routine use in centers with more limited resources. The molecular subtypes of MBs from 32 Thai patients, aged 0.5 to 35 years, were first determined by NanoString. These results were then compared with those obtained using a combination of limited immunohistochemistry (IHC) (β-catenin, GAB-1, YAP-1, p75-NGFR, OTX2) and CTNNTB exon 3 mutation analysis. By NanoString assay, there were 6 MBs (19%) in the wingless (WNT) group, 8 (25%) in the sonic hedgehog (SHH) group, 7 (22%) in group 3, and 11 (34%) in group 4. Although β-catenin immunostaining missed 4/6 WNT MBs, CTNNTB mutation analysis confirmed all WNT MB cases with amplifiable DNA. The IHC panel correctly assigned all the other molecular subtypes, except for 1 MB in group 4. Thus, our protocol was able to correctly categorized 31/32 cases or 97% of cases. Our study is the first to report molecular subtypes of MB in Southeast Asia. We found that molecular subgroups of MBs can be reliably assigned using a limited IHC panel of β-catenin, GAB-1, YAP-1, p75-NGFR, OTX2, together with CTNNTB exon 3 mutation analysis. This simplified approach incurs lower cost and faster turnaround time compared with more elaborate molecular methodologies and should be beneficial to centers with reduced laboratory resources.

Medulloblastoma: clinicopathological parameters, risk stratification, and survival analysis of immunohistochemically validated molecular subgroups

BACKGROUND

Medulloblastoma (MB) is a heterogeneous disease, displaying distinct genetic profiles with specific molecular subgroups. This study aimed to validate MB molecular subgrouping using surrogate immunohistochemistry and associate molecular subgroups, histopathological types, and available clinicopathological parameters with overall survival (OS) and progression-free survival (PFS) of MB patients. This study included 40 MBs; immunohistochemical staining, using β-catenin and GRB2-Associated Binding Protein 1 (GAB1) antibodies, was used to classify MB cases into wingless signaling activated (WNT), sonic hedgehog (SHH), and non-WNT/SHH molecular subgroups. Nuclear morphometric analysis (for assessment of degree of anaplasia) and Kaplan-Meier survival curves were done.

RESULTS

MB cases were classified into WNT (10%), SHH (30%), and non-WNT/SHH (60%) subgroups. Histopathological types differed significantly according to tumor location (p< 0.001), degree of anaplasia (p = 0.014), molecular subgroups (p < 0.001), and risk stratification (p = 0.008). Molecular subgroups differed significantly in age distribution (p = 0.031), tumor location (p< 0.001), histopathological variants (p < 0.001), and risk stratification (p < 0.001). OS was 77.5% and 50% after 1 and 2 years, while PFS was 65% and 27.5% after 1 and 2 years, respectively. OS and PFS were associated significantly with histopathological variants (p < 0.001 and 0.001), molecular subgroups (p = 0.012 and 0.005), and risk stratification (p < 0.001 and < 0.001), respectively.

CONCLUSIONS

Medulloblastoma classification based on molecular subgroups, together with clinicopathological indicators, mainly histopathological types; accurately risk stratifies MB patients and predicts their survival.

Extraaxial Cerebellopontine Angle Medulloblastoma with Multiple Intracranial Metastases in Adult: A Rare Case Report with a Review of Literature

Medulloblastoma (MB) is very rare malignant primary brain tumor in adults and its location at cerebellopontine angle (CPA) is even rarer. There are only few case reports of CPA MBs in literature. Most of them are reported in pediatric age groups which are mostly intraaxial. Only 11 cases of extra-axial CPA MBs have been reported so far. The author is reporting a very rare case of adult extra-axial CPA MBs with multiple intracranial metastases. We are also reviewing clinical and radiological features and unusual way of its presentation along with surgical management. Keeping MBs as one of the differential diagnosis for extra-axial CPA tumors is going to increase our spectrum of diagnosis which can lead to alteration in management.

Molecular subgrouping of medulloblastoma based on few-shot learning of multitasking using conventional MR images: a retrospective multicenter study

Background

The determination of molecular subgroups—wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4—of medulloblastomas is very important for prognostication and risk-adaptive treatment strategies. Due to the rare disease characteristics of medulloblastoma, we designed a unique multitask framework for the few-shot scenario to achieve noninvasive molecular subgrouping with high accuracy.

Methods

We introduced a multitask technique based on mask regional convolutional neural network (Mask-RCNN). By effectively utilizing the comprehensive information including genotyping, tumor mask, and prognosis, multitask technique, on the one hand, realized multi-purpose modeling and simultaneously, on the other hand, promoted the accuracy of the molecular subgrouping. One hundred and thirteen medulloblastoma cases were collected from 4 hospitals during the 8-year period in the retrospective study, which were divided into 3-fold cross-validation cohorts (N = 74) from 2 hospitals and independent testing cohort (N = 39) from the other 2 hospitals. Comparative experiments of different auxiliary tasks were designed to illustrate the effect of multitasking in molecular subgrouping.

Results

Compared to the single-task framework, the multitask framework that combined 3 tasks increased the average accuracy of molecular subgrouping from 0.84 to 0.93 in cross-validation and from 0.79 to 0.85 in independent testing. The average area under the receiver operating characteristic curves (AUCs) of molecular subgrouping were 0.97 in cross-validation and 0.92 in independent testing. The average AUCs of prognostication also reached to 0.88 in cross-validation and 0.79 in independent testing. The tumor segmentation results achieved the Dice coefficient of 0.90 in both cohorts.

Conclusions

The multitask Mask-RCNN is an effective method for the molecular subgrouping and prognostication of medulloblastomas with high accuracy in few-shot learning.