Clinical characteristics and abandonment and outcome of treatment in 67 Chinese children with medulloblastoma

Treatment Outcomes of Childhood Medulloblastoma with the SIOP/UKCCSG PNET-3 Protocol

OBJECTIVES

To retrospectively compare the overall and event-free survival rates of patients with standard and high risk medulloblastoma who received postoperative radiotherapy (RT) followed by maintenance chemotherapy.

METHODS

The study included 48 patients with medulloblastoma who were treated and followed-up between 2005 and 2021. Patients were classified according to the Chang classification because no molecular analysis was done. Immediately after surgery all patients received postoperative RT followed by eight cycles of chemotherapy (SIOP/UKCCSG PNET-3 protocol); if thrombocytopenia developed, carboplatin was replaced by cisplatin to avoid treatment delay. The clinical characteristics, risk categories and treatment outcomes of all patients were analyzed.

RESULTS

The mean age of the 48 patients (26 males, 22 females) at diagnosis was 7.27±4.21 y. The median start time of RT after surgery was 37 (range 19-80) d. The median follow-up was 56 (3-216) mo. The 5-year event-free survival was 61.2±10% in the high-risk group and 82.5±11.5% in the standard-risk group. The 5-year overall survival was 73.2±7.1%; it was 61.2±10% and 92.9±6.9% for high- and standard-risk patients, respectively (p = 0.026).

CONCLUSIONS

The outcomes of patients who were started on the modified SIOP/UKCCSG PNET-3 chemotherapy protocol, in which RT was begun as soon as possible after surgery, were comparable to those of current treatment protocols. Although a definitive conclusion is difficult, given the limited number of patients in the present study, authors suggest that their treatment protocol is a viable option for centers with limited facilities (such as an inability to perform molecular analysis).

Prognostic significance of molecular subgroups in survival outcome for children with medulloblastoma in Malaysia

Introduction

Advancements in genomic profiling led to the discovery of four major molecular subgroups in medulloblastoma (MB), which have now been incorporated into the World Health Organization classification of central nervous system tumors. The current study aimed to determine the prognostic significance of the MB molecular subgroups among children in Malaysia.

Methods

We assembled MB samples from children <18 years between January 2003 and June 2017 from four pediatric oncology centers in Malaysia. MB was sub-grouped using 850k DNA methylation testing at German Cancer Research Centre, Heidelberg, Germany.

Results

Fifty samples from patients diagnosed and treated as MB were identified. Two (4%) of the 50 patients' tumor DNA samples were insufficient for analysis. Of the remaining 48 patients, 41 (85%) samples were confirmed as MB, while for 7 (15%) patients, DNA methylation classification results were discrepant with the histopathological diagnosis of MB, with various other diagnoses. Of the 41 MB patients, 15 patients were stratified as standard-risk (SR), 16 patients as high-risk (HR), and ten as infants (age <3 years old). Molecular subgrouping of the whole cohort revealed four (14%) WNT, 11 (27%) SHH, 10 (24%) Group 3, and 16 (39%) Group 4. Treatment abandonment rates for older children and infants were 22.5% and 10%, respectively. After censoring treatment abandonment, for SR patients, the 5-year event-free survival (EFS) and overall survival (OS) were 43.1% ± 14.7% and 46.9 ± 15.6%, respectively, while in HR, 5-year EFS and OS were both 63.6% ± 14.5%. Infants had a 5-year EFS and OS of 55.6% ± 16.6% and 66.7% ± 15.7%, respectively. WNT tumors had the best 5y-OS, followed by Group 3, Group 4, and SHH in children ≥3 years old. In younger children, SHH MB patients showed favorable outcomes.

Conclusion

The study highlights the importance of DNA methylation profiling for diagnostic accuracy. Most infants had SHH MB, and their EFS and OS were comparable to those reported in high-income countries. Due to the relatively small cohort and the high treatment abandonment rate, definite conclusions cannot be made regarding the prognostic significance of molecular subgroups of MB. Implementing this high-technology investigation would assist pathologists in improving the diagnosis and provide molecular subgrouping of MB, permitting subgroup-specific therapies.

Clinicomorphological and molecular analysis of medulloblastoma and association with survival: A single tertiary care center experience

BACKGROUND

Medulloblastoma (MB) is a heterogeneous disease, displaying distinct genetic profiles, with specific molecular subgroups. Various clinical, pathological and molecular variables have been associated with disease outcome and therefore utilised in risk stratification of patients.

OBJECTIVES

To perform molecular classification of medulloblastoma using surrogate immunohistochemistry (IHC) and associate molecular subgroups, histopathological types, and available clinicopathological parameters with overall survival (OS) of MB patients.

RESULTS

This study included 65 medulloblastoma patients. Immunohistochemical staining, using β-catenin YAP1 and GRB2-Associated Binding Protein 1 (GAB1) antibodies was used to classify MB cases into wingless signalling (WNT) activated, sonic hedgehog (SHH) activated, and non-WNT/non-SHH molecular subgroups. The relevant statistical analysis was done using GraphPad Prism version 9.3.0. Histological patterns included classic (40 cases, 62%), desmoplastic nodular (D/N) (14 cases, 22%), large cell/anaplastic (LC/A) (9 cases, 13%), medulloblastoma with extensive nodularity (MBEN) (1 case, 1.5%) and one special subtype, i.e., medulloblastoma with myogenic and melanotic differentiation. Molecular subgroups included WNT (4 cases, 6%), SHH (34 cases, 52%), and non-WNT/non-SHH (27 cases, 42%) subgroups. Histopathological types differed significantly according to tumor location, degree of anaplasia and molecular subgroups. Molecular subgroups differed significantly in age distribution and tumor location. The probability of survival was 78% and 68% after 1 and 2 years, respectively. Infants (<3 years of age), LC/A pattern, and TP53-mutant status among SHH subgroup conferred poor prognosis in our study. At the end of the study (at 65 months of maximum follow-up period) probability of survival was 51%.

CONCLUSIONS

Immunohistochemical analysis helps in molecular classification of medulloblastoma in majority of the cases as well as helps in predicting prognosis and treatment response.

Treatment barriers and clinical outcome of children with medulloblastoma in China: a report from the Chinese Children's Cancer Group (CCCG)

Background

Medulloblastoma (MB) is the most common malignant central nervous system tumor of childhood. Management requires interdisciplinary care and is associated with unique challenges in developing regions. Here, we report the characteristics, clinical outcome and treatment barriers for Chinese children with MB based on a multi-institutional cohort from the Chinese Children’s Cancer Group (CCCG).

Methods

Retrospective cohort study among 12 Chinese pediatric oncology units from the CCCG Brain Tumor Workgroup on patients aged <18 years diagnosed with MB from 2016 to 2019.

Results

221 patients (male:female = 138:83) were included, 175 (79%) were ≥3 years of age, and 46 (21%) <3 years. 177 patients (80%) were completely staged, among which 50 (28%) had metastasis and 70 (40%) were considered to have high-risk (HR) disease. Gross/near-total resection was achieved in 203 patients (92%). In patients where molecular grouping could be assigned, 19 (16%), 35 (29%), and 65 (54%), respectively had WNT-activated, SHH-activated, and Group 3/4 MB. The median duration between resection and initiation of adjuvant therapy was 36 days. Respective 2-year PFS and OS rates were 76.0 ± 3.0% and 88.0 ± 2.3%. PFS was significantly associated with age, metastatic status and clinical risk grouping. Chemotherapy use during CSI or alkylator choice were not significant predictors for patient outcome.

Conclusions

We reported the clinical profiles and outcome from the largest cohort of Chinese children with MB after multi-modal therapy. Strengths and limitations on the local provision of neuro-oncology service are identified.

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.

Impact of universal health coverage on childhood cancer outcomes in Indonesia

BACKGROUND

Starting from 2014, the Indonesian government has implemented Universal Health Coverage (UHC) with the aim to make healthcare services accessible and affordable to all Indonesian citizens. A major reason for childhood cancer treatment failure in low- and middle-income countries, particularly among families with low socioeconomic status (SES), is abandonment of expensive cancer treatment. Our study compared childhood cancer treatment outcomes of the overall, low, and high SES population before and after introduction of UHC at a large Indonesian academic hospital.

METHODS

Medical records of 1040 patients diagnosed with childhood cancer before (2011-2013, n = 506) and after (2014-2016, n = 534) introduction of UHC were abstracted retrospectively. Data on treatment outcome, SES, and health-insurance status at diagnosis were obtained.

FINDINGS

After introduction of UHC, the number of insured patients increased from 38% to 82% (P < 0.001). Among low SES population, insurance coverage increased from 40% to 85% (P < 0.001), and among high SES population from 33% to 77% (P < 0.001). In the overall population, treatment abandonment decreased from 36% to 22% (P < 0.001). Event-free survival estimates at four years after diagnosis of overall population improved from 16% to 22% (P < 0.001). Hazard ratio for treatment failure was 1.26 (CI: 1.07-1.48, P = 0.006) for uninsured versus insured patients. In the low SES population, treatment abandonment decreased from 36% to 19% (P < 0.001). Event-free survival estimates at four years after diagnosis of low SES population improved from 14% to 22% (P < 0.001).

INTERPRETATION

Introduction of UHC in Indonesia contributed significantly to better treatment outcome and event-free survival of children with cancer from low SES families.

Treatment abandonment and refusal among children with central nervous system tumors in Jordan

BACKGROUND

Treatment abandonment and refusal are reported to contribute significantly to poor survival of children with cancer in low- and middle-income countries. We aimed to assess this phenomenon among children diagnosed with central nervous system (CNS) tumors in Jordan.

METHODS

We retrospectively reviewed the medical charts of children <18 years diagnosed with CNS tumors (2010-2020). Patients who abandoned or refused part of treatment were reviewed for their clinical characteristics, social circumstances, and possible reasons. We excluded patients referred for second opinion, radiotherapy only, or who traveled abroad for treatment.

RESULTS

Four hundred seventy-three Jordanian children were identified; 12 families (2.5%) abandoned treatment, and 15 refused part of therapy (3%). Most patients were females (67%) and most had good or moderate performance status (89%). Most families (93%) lived within 2 hours from King Hussein Cancer Center. Most parents were university graduates (71%) and all fathers were employed, while 71% of mothers were housewives. The most common reasons to abandon or refuse therapy were treatment intensity in view of poor tumor outcome or bad quality of life, conflicting recommendations from other health care providers, "personal beliefs" against chemotherapy, and preference to use alternative medicine.

CONCLUSIONS

Treatment abandonment and refusal in Jordanian children with CNS tumors is low. Universal cancer insurance, high level of education in the country, centralized cancer care in one institution, and the twinning program likely contributed to our low incidence. Improving knowledge on CNS tumors and better community rehabilitation and supportive services may help further decrease the abandonment and treatment refusal rate.

Treatment Refusal and Abandonment Remain Major Concerns Despite Good Outcomes with Multi-Modality Management in Pediatric Medulloblastoma: Experience from a Cancer Center in Eastern India

Context: Survival in medulloblastoma, the most common pediatric brain tumor, has lagged behind in developing countries in comparison to the West. Aim: The aim of this study was to analyze the clinical profile and outcome in a cancer center in Eastern India. Methods: Twenty-nine children were retrospectively analyzed over 6 years. Results: Vomiting (79%), headache (69%), and unsteadiness (55%) were the presenting complaints. The majority (67%) had classical histology. High-risk (HR) disease (61.6%) exceeded average-risk (AR) (38.4%) disease in numbers. Treatment-refusal (27.6%) and abandonment (6.9%) were major concerns. Four-year EFS was 81% and 52%, excluding and including refusal/abandonment, respectively. There was no relapse/progression among AR patients. Four-year EFS in HR was 63%. Posterior fossa syndrome (37.5%), febrile neutropenia (29%), and ototoxicity (16.7%) were the main treatment-related morbidities. Implications: Following this audit, patient tracking to reduce abandonment, coordination to limit delay in postsurgical referral, developing strategies for molecular subgrouping, and reducing cumulative cisplatin exposure were measures adopted to improve outcome in the unit.

Retrospective investigation of hereditary syndromes in patients with medulloblastoma in a single institution

PURPOSE

To investigate the incidence rate of hereditary disease in patients with medulloblastoma.

METHODS

The genetic reports of 129 patients with medulloblastoma from January 2016 to December 2019 were retrospectively analyzed. A panel sequence of 39 genes (Genetron Health) were used for all patients to evaluate the tumor subgroup. Four genes (TP53, APC, PTCH1, SUFU) were screened to routinely rule out germline mutation.

RESULTS

Five patients (3.9%) were found with hereditary disease, and all belonged to the sonic hedgehog (SHH) subgroup. Two patients were retrospectively diagnosed with Gorlin-Goltz disease with germline PTCH1 and SUFU mutations. One patient (PTCH1 mutation) accepted whole craniospinal irradiation and had scalp nevoid basal cell carcinoma 5 years later. The other patient (SUFU mutation) accepted chemotherapy and had local tumor relapse 1 year later. Three patients were diagnosed with Li-Fraumeni syndrome and carried the TP53 mutation; all three patients died. One of the patients had bone osteosarcoma, while all three had early tumor relapse.

CONCLUSION

Patients with SHH medulloblastoma should routinely undergo genetic testing. We propose that whole genome, whole exome sequence, or custom-designed panel-targeted exome sequencing should be performed.

Challenges and opportunities for managing pediatric central nervous system tumors in China

Central nervous system (CNS) tumors represent the most deadly cancer in pediatric age group. In China, thousands of children are diagnosed with CNS tumors every year. Despite the improving socioeconomic status and availability of medical expertise within the country, unique challenges remain for the delivery of pediatric neuro-oncology service. In this review, we discuss the existing hurdles for improving the outcome of children with CNS tumors in China. Need for precise disease burden estimation, lack of intra- and inter-hospital collaborative networks, high probability of treatment abandonment, along with financial toxicities from treatment represent the key challenges that Chinese healthcare providers encounter. The tremendous opportunities for advancing the status of pediatric neuro-oncology care in and beyond the country are explored.

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.

Treatment abandonment in childhood acute lymphoblastic leukaemia in China: a retrospective cohort study of the Chinese Children's Cancer Group

OBJECTIVES

Before 2003, most children with acute lymphoblastic leukaemia (ALL) abandoned treatment, with only approximately 30% treated in China. With the development of national insurance for underprivileged patients, we assessed the current frequency and causes of treatment abandonment among patients with ALL who were enrolled in the Chinese Children's Cancer Group ALL protocol between 2015 and 2016.

METHODS

Demographic, clinical and laboratory data on patients who abandoned treatment, as well as economic and sociocultural data of their families were collected and analysed. General health-related statistics were retrieved from publicly accessible databanks maintained by the Chinese government.

RESULTS

At a median follow-up of 119 weeks, 83 (3.1%, 95% CI 2.5% to 3.8%) of the 2641 patients abandoned treatment. Factors independently associated with abandonment included standard/high-risk ALL (OR 2.62, 95% CI 1.43 to 4.77), presence of minimal residual disease at the end of remission induction (OR 3.57, 95% CI 1.90 to 6.74) and low-income economic region (OR 3.7, 95% CI 1.89 to 7.05). According to the family members, economic constraints (50.6%, p=0.0001) were the main reason for treatment abandonment, followed by the belief of incurability, severe side effects and concern over late complications.

CONCLUSIONS

The rate of ALL treatment abandonment has been greatly reduced in China. Standard/high-risk ALL, residence in a low-income region and economic difficulties were associated with treatment abandonment.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR-IPR-14005706, pre-results.

Medulloblastoma: Distinctive Histo-Molecular Correlation with Clinical Profile, Radiologic Characteristics, and Surgical Outcome

OBJECTIVE

Medulloblastoma (MB) is a heterogenous tumor, and the prognosis is influenced by various clinical, histological, and molecular factors. The aim of the study is to determine the clinical profile and radiologic characteristics among the histo-molecular subgroups, the predictors of surgical outcome, and the pattern of relapse in pediatric and adult MB.

METHOD

An analysis of 118 patients of MB who underwent surgical treatment at National Institute of Mental Health and Neurosciences, India, over a 7-year period (2005-2011) is presented. The clinical profile, radiologic characteristics, surgical nuances, and survival patterns are discussed. The relevant statistical analysis was done using SPSS software, version 22.0.

RESULTS

The mean age of the cohort was 12 years (12.3 ± 8.7). The primary manifestation was raised intracranial tension headache in 53 patients (44.9%), which was the predominant symptom in large cell/anaplastic (LCA)- and WNT-activated subgroups. The median preoperative Karnofsky performance score was 60 (60.6 ± 12.9). Vermian and hemispheric location of tumor was most commonly observed in non-WNT/non-SHH (groups 3 and 4; 91.7%) and SHH-activated (42.9%) subgroups, respectively. Ninety-two patients (78%) underwent preoperative ventriculoperitoneal shunts (VPS) for obstructive hydrocephalus (HCP) and 14 patients (11.8%) underwent VPS in the postoperative period. The median overall survival (OS) for the whole group was 82.1 ± 5.7 months and the median recurrence-free survival was 51.0 ± 4.8 months. While radiotherapy had a significant influence on OS, progression-free survival was influenced by radiotherapy as well as chemotherapy in both pediatric and adult cohort. Desmoplastic/nodular subtype and WNT-activated subgroup had the best prognosis; LCA and non-WNT/non-SHH had the worst prognosis.

CONCLUSIONS

Majority of the patients were pediatric in the study. Age, hemispheric location of tumor, extent of resection, and adjuvant treatment status were the important clinical prognostic factors for survival. Surgery for MB is formidable, and VPS can be considered in persistent symptomatic and progressive HCP. Our study on pediatric and adult MB validates the prognostic significance of various clinical, radiologic, and histo-molecular parameters of MB.

Improvement in treatment abandonment in pediatric patients with cancer in Guatemala

BACKGROUND

Treatment refusal and abandonment are major causes of treatment failure for children with cancer in low- and middle-income countries (LMICs), like Guatemala. This study identified risk factors for and described the intervention that decreased abandonment.

METHODS

This was a retrospective study of Guatemalan children (0-18 years) with cancer treated at the Unidad Nacional de Oncología Pediátrica (UNOP), 2001-2008, using the Pediatric Oncology Network Database. Treatment refusal was a failure to begin treatment and treatment abandonment was a lapse of 4 weeks or longer in treatment. The impact of medicina integral, a multidisciplinary psychosocial intervention team at UNOP was evaluated. Cox proportional hazards analysis identified the effect of demographic and clinical factors on abandonment. Kaplan-Meier analysis estimated the survival.

RESULTS

Of 1,789 patients, 21% refused or abandoned treatment. Abandonment decreased from 27% in 2001 to 7% in 2008 following the implementation of medicina integral. Factors associated with increased risk of refusal and abandonment: greater distance to the centre (P < 0.001), younger age (P = 0.017) and earlier year of diagnosis (P < 0.001). Indigenous race/ethnicity (P = 0.002) was associated with increased risk of abandonment alone. Abandonment correlated with decreased overall survival: 0.57 ± 0.02 (survival ± standard error) for those who completed therapy versus 0.06 ± 0.02 for those who abandoned treatment (P < 0.001) at 8.3 years.

CONCLUSION

This study identified distance, age, year of diagnosis and indigenous race/ethnicity as risk factors for abandonment. A multidisciplinary intervention reduced abandonment and can be replicated in other LMICs.

Clinicopathological features and microsurgical outcomes for giant pediatric intracranial tumor in 60 consecutive cases

PURPOSE

Giant pediatric intracranial tumor (GPIT) remains to be a challenging disease with high morbidity and mortality.

METHODS

The clinical data of 60 patients under 18 years of age operated on with GPIT (≥5 cm in diameter) were retrospectively analyzed.

RESULTS

Gross total resection was achieved in 46 cases (77%) and subtotal resection was obtained in 14 cases (23%). Ninety percent (47/52) of the cases with obstructive hydrocephalus were resolved remarkably and only 10% (5/52) of the patients needed a ventriculoperitoneal shunt after tumor resection. Postoperative histopathological type revealed malignant brain tumors in 51 cases (85%). The most common neoplasm was medulloblastoma; other types include the following: ependymoma, pilocytic astrocytoma, mixed glioma, primitive neuroectoderm tumor (PNET), subependymal giant cell astrocytoma, gangliocytoma, gliosarcoma, choroid plexus carcinoma, and atypical teratoid rhabdoid tumor (AT/RT). Benign histopathological categories include the following: craniopharyngioma, choroid plexus papilloma, and meningioma. No death or serious complications occurred after the operation. However, transient subcutaneous effusion occurred in 14 patients postoperatively, nerve injury including the posterior cranial nerve in two cases and abduction nerve in one case, and mutism and pulmonary infection were observed in two cases, respectively. The follow-up period ranged from 1 to 72 months, with an average of 32 months. Poor prognosis occurred significantly in the high-grade malignant tumors and PNET, AT/RT, and gliosarcoma were implicated in the death of patients within 1 year.

CONCLUSIONS

To the best of our knowledge, the present study is the first description of clinicopathological features and the largest case analysis for GPIT. Optimal outcomes for GPIT were achieved by strict evaluation and perioperative management as well as microsurgical skills.

The expression of FAT1 is associated with overall survival in children with medulloblastoma

PURPOSE

The FAT1 gene is involved in some cancers; however, its role in medulloblastoma is less clear. This study investigated the effects of FAT1 expression on the prognosis of medulloblastoma patients.

METHODS

Whole exome sequencing was undertaken in 40 medulloblastoma patient samples. FAT1 mRNA and protein expression levels in normal and brain tumor tissues were determined by fluorescence quantitative PCR and immunohistochemistry, respectively. The association of FAT1 expression with overall survival (OS) was examined by Kaplan-Meier curve analysis with a log-rank test. Following lentiviral-mediated FAT1 knockdown using shRNA in Daoy cells, proliferation, Wnt signaling, and β-catenin protein expression were determined.

RESULTS

Eight FAT1 missense mutations were detected in 7 patients. FAT1 mRNA expression in tumors was significantly lower than in adjacent normal tissue (p = 0.043). The OS of patients with high FAT1 protein expression was significantly longer than that of patients with low FAT1 protein expression (median survival time: 24.3 vs 4.8 months, respectively; p = 0.002). shFAT1 cells had significantly higher proliferation rates than shControl cells (p≤0.028). Furthermore, the mRNA expression of LEF1, β-catenin, and cyclin D1 was significantly upregulated in shFAT1-Daoy cells (p≤0.018).

CONCLUSIONS

Low FAT1 expression was associated with poor prognosis in children with medulloblastoma. Furthermore, FAT1 may act on Wnt signaling pathway to exert its antitumor effect.

Impact of tumor location and fourth ventricle infiltration in medulloblastoma

BACKGROUND

Medulloblastoma is the most common intracranial malignancy in children; with comprehensive treatment the 5-year overall survival (OS) is now greater than 80 %. Only few studies have addressed the relation of tumor location with patient's prognosis. Based on experiences in our institution, we further classified the tumor location. This study aimed to investigate the impact of tumor location and fourth ventricle infiltration in medulloblastoma (MB) prognosis.

METHODS

We retrospectively followed all MB patients at the Beijing Tiantan Hospital between 2004 and 2007 to investigate treatment outcomes and prognostic factors in MB patients. The data of 119 patients were collected. Tumor removal was performed in all patients, and all patients received postsurgical radiotherapy or chemotherapy. The patients were subclassified into three subtypes according to tumor location and tumor infiltration into the fourth ventricular floor (V4 floor). The prognostic factors were analyzed using Kaplan-Meier and Cox regression analysis.

RESULTS

The median follow-up period was 75 months (range, 6-127 months). A total of 65 patients experienced recurrence or progression, and 56 patients were still alive at the time of follow-up. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 47.1 ± 4.6 % and 54.6 ± 4.6 %, respectively.

CONCLUSIONS

According to the multivariate analysis, large cell and anaplastic (LC/A) subtype, patient age, and metastasis were found to be independent prognostic factors. Tumors with V4 floor infiltration exhibited a trend toward recurrence (P = 0.054). This investigation is the largest single-institution study of MB cases in China. The LC/A subtype, patient age, and metastasis were important prognostic factors. V4 floor infiltration was correlated with metastasis and younger age.