466P - Re-irradiation therapy for pediatric brainstem tumours: 20 years of clinical experience

Background

Brain stem tumors are among the most severe oncological diseases in children. The only real method of help remains radiation therapy, which makes it possible to alleviate the severity of neurological disorders, but for most patients, the effect achieved, regardless of the type of ionizing radiation used, is temporary and after various periods (from 3 months to several years), the tumor resumes growth. The main purpose of our work was to determine the possibilities and prospects of repeated radiation therapy in children with diffuse brain stem tumors.

Methods

In the period 1998-2022, analysis of short and long-term results of 132 children and adolescents with brainstem tumors treated at the Russian Scientific Center of Roentgenoradiology were evaluated. Out of 132 patients treated at RNCRR, 60 children were selected whose remission lasted more than 9 months and the Lansky scale of more than 40 points for re-irradiation.

Results

As a result of re-irradiation, out of 45 children with a Lansky status of 40-50 points, it was improved in 36 (80%). An additional 15 children were included in the group with an initial Lansky status of 70-90 points, initially represented by one child, and only 9 patients' condition worsened or did not change. The median life expectancy in the group of patients after one course of radiation therapy was 13.9 months, but in the group of those treated repeatedly - 22.6 months.

Conclusions

Re-irradiation using 30.0 to 45.0 Gy in standard fractionation in combination with adequate accompanying therapy in 90% of cases allows an increase in the remission period in dense tumors and temporarily improve the quality of life in cystic solid tumors.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Federal State Budgetary Institution Russian Scientific Center of Roentgenoradiology (RSCRR) of the Ministry of Healthcare of the Russian Federation (Russian Scientific Center of Roentgenoradiology).

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.