Malignant hemispheric tumors in childhood

Area of Science:

• Pediatric Neurosurgery
• Pediatric Oncology
• Neuro-oncology

Background:

• Malignant hemispheric tumors in children are aggressive, but some present with prolonged pre-operative evolution.
• A significant proportion of malignant tumors may arise from the malignant transformation of benign precursors.
• The study reviews outcomes for 64 pediatric patients treated over two decades.

Purpose of the Study:

• To analyze the clinical characteristics, outcomes, and prognostic factors of malignant hemispheric tumors in children.
• To investigate the potential for malignant transformation of benign lesions.
• To evaluate the impact of tumor grading and radiotherapy on patient outcomes.

Main Methods:

• Retrospective review of 64 pediatric patients with malignant hemispheric tumors treated between 1970 and 1989.
• Analysis of tumor evolution, occurrence of secondary malignancies, and survival rates.
• Comparison of functional outcomes based on treatment modalities, including radiotherapy.

Main Results:

• 20% of malignant tumors had a pre-operative evolution exceeding 6 months, suggesting malignant transformation.
• Five patients developed a second malignancy, often acute lymphoblastic leukemia.
• High-grade astrocytomas (III-IV) showed a poor prognosis, underscoring the importance of grading.
• Malignant ependymomas had a 5-year survival rate of nearly 50%, indicating modest prognostic value of grading.
• Radiotherapy's harmful effects were assessed by comparing functional outcomes.

Conclusions:

• Early surgical intervention for all diagnosed benign hemispheric tumors is recommended to prevent malignant transformation.
• Accurate tumor grading is essential for predicting outcomes in pediatric astrocytomas.
• Grading ependymomas has limited prognostic significance.
• Further research is needed to fully understand the long-term effects of radiotherapy in pediatric neuro-oncology.