Second brain tumors following central nervous system radiotherapy in childhood

Abstract

Objective: The second tumour (ST) occurrence is a relatively uncommon late complication of radiotherapy but represents one of the most significant issues, especially in childhood oncology. We describe our experience with patients who developed second brain neoplasm following cranial irradiation in childhood. Methods: We identified nine patients who received radiotherapy owing to central nervous system tumour in childhood and subsequently developed the second brain tumour. The full clinical and radiological documentation and histopathological reports were reviewed. Risk factors such as age at irradiation, latency period to ST diagnosis, radiotherapy doses and volumes and other therapy methods were evaluated. We correlated the ST location with the three levels of irradiation dose (high, .40 Gy; medium, 25-40 Gy; and low ,25 Gy).Results: Five meningiomas and four gliomas occurred as the ST after the mean time of 11.7 years after radiotherapy. The average age of children during irradiation was 4.6 years. The shorter latency time to the ST induction was found in children treated with chemotherapy (9 years vs 17.2 years). Seven STs developed in the area of high and moderate dose (.25 Gy), only two low-grade gliomas appeared in the low-dose region. Conclusion: Our data suggest that the STs usually develop in the brain tissues that received doses .25 Gy in patients irradiated at a young age. Advances in knowledge: The low-dose volume seems not to be so significant for second brain neoplasm induction. Therefore, the modern intensity-modulated radiotherapy technique could be safely applied in paediatric patients.

Risk of Second Primary Neoplasms of the Central Nervous System

“… 8 , 18 These findings align with previous reports of CNS radiation-associated tumors in the setting of pediatric atomic bomb exposure, 19 , 20 tinea capitis management, 6 , 21 , 22 and primary cancer treatment. 23 , 24 , 25 Our estimated CIR of subsequent CNS tumors among radiated pediatric patients aligns with published estimates ranging from 1% to 28% at 20 years. 26 , 27 , 28 , 29 In contrast, adults have elevated rates of SP CNS tumors regardless of prior cranial radiation, likely driven by the higher incidence rates of brain tumors in the late adult to elderly period compared with early adulthood.…”

Characteristics and Outcomes of Second Malignant Neoplasms after Childhood Cancer Treatment: Multi-Center Retrospective Survey

“…The most important risk factor for the development of second CNS tumors is cranial radiation, and meningioma and glioma have been reported to be common therapy-related brain tumors ( 19 20 ). In our present cohort, only 5 of 10 (50%) second CNS tumor cases were associated with radiation, and most of these patients had glioma and seemed to require a longer latency period than patients who did not receive cranial radiation.…”

“…In our present cohort, only 5 of 10 (50%) second CNS tumor cases were associated with radiation, and most of these patients had glioma and seemed to require a longer latency period than patients who did not receive cranial radiation. Typically, meningioma associated with radiation requires a long latency period (> 10 years) ( 19 20 21 ), so it was not included in our present study series. In addition, our present study surveyed the patients who received chemotherapy and did not include those who received radiotherapy alone for primary CNS tumors.…”

Childhood Cancer: Occurrence, Treatment and Risk of Second Primary Malignancies

“…Surprisingly, after 20 years this trend was reversed and no significant difference in the risk of SPMs was observed between irradiated and non-irradiated patients. In a more recent study, Chojnacka et al [ 328 ] investigated the development of SPMs in pediatric CNS patients who received EBRT at an average age of 4.6 years. Among 1404 children, only 9 received EBRT and developed an SPM as five meningiomas and four gliomas with a mean latency of 11.7 years.…”