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

Adjuvant therapy for brain tumors in LMICs: A systematic review of barriers and possible solutions

BACKGROUND

Adjuvant therapy is an important tool in the arsenal of brain tumor management and can improve patients' outcomes significantly but low- and middle-income countries (LMICs) often face challenges in provision. Therefore, our study aims to highlight barriers and strategies to adjuvant therapy of brain tumors in low-resource settings.

METHOD

A comprehensive search of literature was conducted using PubMed, CINAHL, Google Scholar, and Scopus, from inception to October 20, 2022. The review included studies on adjuvant therapy for brain tumors in LMICs and identified themes using the National Surgical, Obstetric, and Anesthesia Plan (NSOAP) domains.

RESULTS

32 studies were included in the review. The most reported barriers to adjuvant care were limited access to healthcare (14 %), limited access to chemotherapy and radiation equipment (25 %), and traditional or alternative medications (11 %). Strategies for improvement include improving the availability of specialized radiation oncology training (8 %) and improving access to neuro-diagnostics and neurotherapeutics (12 %). In addition, efforts to subsidize treatment (4 %) and provide financial coverage through the Ministry of Health (4 %) can help to address the high cost of care and improve access to funding for chemotherapy. Finally, establishing documentation systems and registries (16 %), implementing standardized national treatment guidelines (8 %) can help to improve overall care for brain tumor patients in LMICs.

CONCLUSION

A multimodal approach of strategies targeting workforce, infrastructure, service delivery, financing, and information management is needed to improve adjuvant care for brain tumors. International collaboration and partnerships can also play a key role in addressing barriers and improving care in LMICs.

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.

Safety and efficacy of concurrent carboplatin during full-dose craniospinal irradiation for high-risk/metastatic medulloblastoma in a resource-limited setting

PURPOSE

To assess the safety and efficacy of concurrent carboplatin during craniospinal irradiation (CSI) in high-risk/metastatic medulloblastoma defined as either residual tumor >1.5 cm² or leptomeningeal metastases.

METHODS

This single-arm combined prospective (2005-2011) and retrospective (2011-2019) study was undertaken at a tertiary care cancer center in India. Following surgery, patients with newly diagnosed high-risk/metastatic medulloblastoma received concurrent carboplatin (35 mg/m² ) for 15 days (day 1 to day 15) during CSI plus posterior fossa/tumor bed boost, followed by six cycles of standard adjuvant chemotherapy.

RESULTS

All 97 patients completed their planned course of radiotherapy without interruptions, except for two (2.1%) patients who had brief gaps due to treatment-related toxicity. Grade 3-4 anemia, neutropenia, thrombocytopenia, and febrile neutropenia were seen in four (4.1%), 41 (42.2%) 21 (21.6%), and 18 (18.6%) patients, necessitating packed cell transfusion, granulocyte colony-stimulating factor, and platelet support in five (5.1%), 41 (42.2%), and five (5.1%) patients, respectively, during the concurrent phase. Following myelorecovery, 92 (94.9%) patients completed the planned six cycles of standard adjuvant systemic chemotherapy. There were no treatment-related deaths during the concurrent chemo-radiotherapy phase, while three (3.1%) toxic deaths were ascribed to adjuvant chemotherapy-related complications. At a median follow-up of 82 months, the 5-year Kaplan-Meier estimates of progression-free survival and overall survival were 60.2% and 62.1%, respectively. On univariate analysis, leptomeningeal metastases (M0/M1 vs. M2/M3) and histological subtype (large cell/anaplastic vs. others) emerged as significant prognostic factors for survival.

CONCLUSION

Addition of concurrent carboplatin to RT as radiosensitizing chemotherapy is a simple and effective way of treatment intensification in high-risk/metastatic medulloblastoma.