Organs at risk
There is a risk of short-term nerve toxicity such as dizziness, nausea, headache and long-term neuropsychiatric changes. Antiemetic treatment should be considered before starting treatment. Long-term neuropsychiatric changes may depend on multiple factors such as age, and if chemotherapy is administered simultaneously (especially high-dose MTX). Those at the highest risk are patients over 60 years who receive whole brain irradiation after high-dose MTX.
Blood and bone marrow
Large amounts of bone marrow is included in the radiation field for the CNS axis. Counts with differential counts must be taken during and for a time after treatment.
Lens of the eye
A dose of over 4-6 Gy must often be accepted to obtain sufficient coverage to structures near the lamina cribrosa. This may pose a risk for cataract development in some patients.
The dosages used are often lower than the tolerance dose for adults, however, endocrine function should be followed long after treatment in children.
The entire spinal column is irradiated. Even if the doses are small, some growth inhibition may occur.
Total CNS axis is irradiated as part of intensive treatment protocols, which collectively has a negative influence on fertility. The dose to the testicles should be minimized as much as possible by shielding. The ovaries in girls and women at a fertile age will be very close to the spinal cord fields and are difficult to shield.