Guidelines for Complications of Cancer Treatment Vol VIII Part B

IQ decline is associated with several patient andtreatment related risk factors such as younger age at timeof treatment, longer time since treatment, hydrocephalus,RT schedule and dose, volume of irradiated normal brain. Loss of cerebral white matter and failure to develop whitematter at a rate appropriate to the developmental stagemay be responsible for changes in IQ score. Decline in IQ function after CSI is estimated to be 4points per years and is cumulative. Young age andradiation dose were the most significant factorinfluencing fall in IQ score. Decline in performancequotient (PQ) is more than verbal quotient (VQ). However, the decline in IQ scores may be of lessermagnitude after focal conformal RT (3D-CRT) asdemonstrated in recent studies. There is paucity ofprospective data about neuropsychological status inpatients with brain tumours, especially for focal partialbrain RT. Studies with relatively short follow up have shown thesuperiority of conformal RT with or without stereotacticguidance (3D-CRT and SCRT) in maintaining long-termcognitive scores when compared to conventional RT(Merchant 2006; Jalali 2006). After RT, reading appears more vulnerable than otheracademic skills and may decline over time despite stableintellectual functioning. Math and spelling performanceremained stable. Supratentorial tumor location andmultiple surgeries were predictive of worse readingperformance. Control of tumor is the most important factor forstabilizing neurocognitive function. In metastatic braintumour control of the disease had shown to havesignificant impact on preserving neurocognitive function.347