Cognitive impairment, a common finding with the brain tumors, may result from the tumor itself or the treatment used: surgery, chemotherapy, or radiotherapy. Surgery for brain tumors improves the cognitive function due to reduction of compression as in case of removal of noninvasive tumors. Stability of cognitive function also was observed after tumor resection, such as tumors of third ventricle. Postoperative cognitive worsening was observed. Postoperative worsening of executive functions may correlate to volume of the operated area. Cognitive deficits may follow radiotherapy by several months to many years. These deficits may be due to vascular injury, local radionecrosis, and cerebral atrophy. This usually involves multiple domains, including memory, attention, executive function, and intelligence. The irradiated volume of brain tissue has great impact on cognition. Intensity-modulated radiotherapy (IMRT) and proton beam therapy result in greater sparing of healthy brain tissue and allow for a more-targeted delivery of radiation and smaller penetration of tissue beyond the tumor consequently reduce the risk of cognitive deficit after radiotherapy. Chemotherapy treatment in brain tumor seems to have a role in cognitive dysfunction deficits. The toxicity of chemotherapy increased when was given during or after radiotherapy. Chemotherapeutic agents, such as BCNU, CDDP, cytosine arabinoside, and intrathecal or intravenous methotrexate, have toxic effect to the CNS. Glioblastoma patients undergoing radiotherapy with concomitant and adjuvant temozolomide treatment do not develop cognitive deterioration. Patients with brain tumors face the challenge of cognitive impairment due to the tumor itself or treatments. Cognitive deficits in processing speed, memory, attention, and executive functions interfere with patients’ daily life activities. Cognitive rehabilitation program has proven to be effective in patients with primary brain tumors. Cognitive impairments have a large impact on self-care, social and professional functioning, and consequently on quality of life. Preventing these late effects is a challenge for the medical team, psychologists, and rehabilitation specialists. Prevention depends in part on being able to predict those at greatest risk. Advances in neurosurgery, chemotherapy, and radiotherapy techniques are helping to a great extent, but may not be totally successful at preventing these late effects.
Part of the book: Neurooncology