Survival of children under 3 years old with medulloblastoma: a study from the Mexican Cooperative Group for Childhood Malignancies (AMOHP)

Impact of treatment and clinical characteristics on the survival of children with medulloblastoma in Mexico

Introduction

Data on medulloblastoma outcomes and experiences in low- and middle-income countries, especially in Latin America, is limited. This study examines challenges in Mexico's healthcare system, focusing on assessing outcomes for children with medulloblastoma in a tertiary care setting.

Methods

A retrospective analysis was conducted, involving 284 patients treated at 21 pediatric oncology centers in Mexico.

Results

High-risk patients exhibited markedly lower event-free survival than standard-risk patients (43.5% vs. 78.3%, p<0.001). Influential factors on survival included anaplastic subtype (HR 2.4, p=0.003), metastatic disease (HR 1.9, p=0.001); residual tumor >1.5cm², and lower radiotherapy doses significantly impacted event-free survival (EFS) and overall survival (OS). Platinum-based chemotherapy showed better results compared to the ICE protocol in terms of OS and EFS, which was associated with higher toxicity. Patients under 3 years old displayed notably lower OS and EFS compared to older children (36.1% vs. 55.9%, p=0.01).

Clinical factors, management, and outcomes of children under 3 years old with central nervous system tumors: single-center experience

PURPOSE

Children under 3 years old represent a notable portion, about 25 to 30%, of all central nervous system tumor (CNS) cases. Their clinical course, prognosis, and treatment significantly differ from older children. This single-center retrospective study aims to comprehensively analyze survival factors in children under three diagnosed with CNS tumors.

METHODS

Between April 2012 and December 2023, cases under 3 years of age with CNS tumors diagnosed at our center were retrospectively evaluated.

RESULTS

Among 279 CNS tumor cases, 42 (15%) were evaluated. The 5-year overall and event-free survival rates were 67.4% (95% CI 47.5-81.1) and 39.8% (95% CI 24.2-55.0), respectively. Gender, symptom onset to diagnosis time, pathological neurological findings at diagnosis, and tumor location did not significantly impact survival (p > 0.05). However, cases with neurological symptoms showed significantly higher event-free survival rates (p < 0.05). Patients with embryonal tumors, metastases, inability for total surgical excision, relapsed/progressive diseases, and who under 1 year old had significantly lower survival rates (p < 0.05). Radiotherapy timing did not affect survival (p > 0.05). Event-free survival rates remained unchanged after the third year.

CONCLUSION

The current treatments have been observed to have a positive impact on survival rates. Nonetheless, there is a need for novel treatments for patients with embryonal tumors, metastases, aged under 1 year, and those where total surgical excision is not feasible or in cases with progressive/relapse disease. This study underscores the importance of the first 3 years regarding relapse, progression, or mortality risk.

Risk-adapted chemotherapy in childhood medulloblastoma

Medulloblastoma is the most common malignant brain tumor in children. The treatment strategy in this tumor mainly includes surgery and radiotherapy, but chemotherapy has been successfully applied in medulloblastoma. The survival rates have improved over the last decade with chemotherapy. The most important prognostic factors were the amount and the extent of metastases, surgery and age. Risk factors have been defined in recent years, but chemotherapy has not been planned according to these defined risk factors on a worldwide basis. The aim of this article was to examine the use of chemotherapy in childhood medulloblastoma according to risk group. A secondary aim was to examine high-dose chemotherapy with autologous stem cell transplantation and the treatment of infant medulloblastoma.

Impact of radiation avoidance on survival and neurocognitive outcome in infant medulloblastoma

Purpose

Concerns about radiotherapy-related neurocognitive sequelae in young children have led to deferral or avoidance of radiation in contemporary treatment for this fragile group of patients. We compared survival and neurocognitive outcome in two groups of infants with medulloblastoma who received adjuvant conventional craniospinal irradiation (csi) or reduced or no radiotherapy during an era of change in the philosophy of infant medulloblastoma treatment.

Patients and Methods

From 1985 to 2007, 29 patients 3 years of age or younger were diagnosed and treated with curative intent in our institution. Children treated before 1994 received adjuvant radiation with chemotherapy; subsequently, radiation was prescribed essentially for disease progression or relapse.

Results

Median age at diagnosis was 24 months (range: 1–36 months); 15 patients (52%) presented with metastatic disease at diagnosis. As part of initial treatment, 8 children received adjuvant radiotherapy with chemotherapy, and 21 children received postoperative chemotherapy only. Five children treated with chemotherapy alone are in prolonged remission. The 5-year event-free and overall survivals were 35.9% ± 9.8% and 50.2% ± 9.6% respectively. Extent of resection, metastatic status, and desmoplastic histology were not found to be significant prognostic factors.

On serial neurocognitive evaluations, patients treated with chemotherapy with or without reduced radiotherapy demonstrated improvement of intellectual function over time. Patients treated with conventional csi exhibited significantly lower intelligence quotient scores and academic performance, with the exception of receptive vocabulary.

Conclusions

Avoidance of conventional csi in treatment of very young children with medulloblastoma appears to be associated with a preserved neurocognitive profile. Neurocognitive evaluation should be integrated into the primary objectives of future infant protocols.

Central nervous system tumors in patients under three years of age: treatment results of a single institute

Eighty-six patients under 3 years of age with central nervous system tumors were retrospectively analyzed between 1972 and 2003. Surgical resection was done in all patients except for those with optic glioma, pons glioma and pineal tumor. Three different chemotherapy regimens were used in different time periods. In 48 patients, the tumor was located in the posterior fossa, and 29 patients had a supratentorial tumor. We had 32 (37.2%) patients with embryonic tumors (21 medulloblastoma, 4 ependymoblastoma, 5 with atypical teratoid rhabdoid and 2 with supratentorial primitive neuroectodermal tumors), 21 (24.4%) with ependymoma, 14 (16.3%) with optic glioma, 10 (11.6%) with astrocytoma, 3 (3.5%) with pons glioma and 6 (7.0%) with others. Overall (OS) and event-free survival rates were 49.5 and 40.9%. OS rates according to the tumor localizations were 40.9 and 68.1% in the posterior fossa and supratentorial localizations, respectively (p=0.001). OS rates were 33.7, 41.3 and 88.8% for the medulloblastoma+primitive neuroectodermal tumor groups, ependymoma and astrocytoma, respectively (p=0.0001). Most of the patients had primitive embryonic tumors (37.2%). The best prognostic factors were tumor localization and histology.