This article is more than 5 years old. Information may no longer be current.
Lower radiation doses, smaller boost volumes minimized intellectual decline in medulloblastoma
Click Here to Manage Email Alerts
Lower doses of craniospinal irradiation and smaller boost volumes can minimize intellectual decrement in patients with medulloblastoma, according to results of a retrospective review.
Researchers evaluated 113 patients treated for medulloblastoma between August 1983 and January 2011 at the Hospital for Sick Children in Toronto. The patients underwent neuropsychological examination, including long-term follow-up for intellectual capacity.
The study participants underwent one of the following craniospinal irradiation regimens, administered with or without chemotherapy:
- Standard-dose irradiation with a posterior fossa boost (n=51);
- Standard-dose irradiation with tumor bed boost (n=9);
- Reduced-dose irradiation with a posterior fossa boost (n=28); or
- Reduced-dose irradiation with tumor bed boost (n=23).
A subcategory of patients developed hydrocephalus necessitating cerebrospinal fluid diversion (n=54). Other neurological complications, such as mutism, were observed in 40 patients.
Researchers performed growth curve analysis to establish stability or deviations in intelligence scores over time.
Patients who underwent reduced-dose irradiation plus tumor bed boost demonstrated the most consistency in long-term intellectual patterns, whereas those treated with higher volumes and larger boost volumes exhibited intellectual diminishment. Complications were related to poorer intellectual outcomes, but notably different patterns of decline were observed between patients who developed hydrocephalus requiring cerebrospinal fluid diversion and those with mutism.
These findings add to the knowledge of intellectual outcomes in medulloblastoma patients, and they may be useful in strategies for treatment de-escalation, according to researchers.
“With biologically based strategies presently well positioned to guide treatment de-escalation in medulloblastoma, our findings are timely,” they wrote. “For instance, patients with WNT medulloblastoma have excellent disease prognosis and are ideal candidates for therapy de-escalation. We have demonstrated that lower craniospinal irradiation dose and smaller boost volume lead to stable intellectual trajectories without seeming to worsen survival.”
Disclosure: The researchers report no relevant financial disclosures.
Click Here to Manage Email Alerts