Chemobrain: Mysteries and the importance of their revelation

Chemotherapy can be associated with both acute and delayed toxic effects on the central nervous system. Among the most commonly reported neurotoxic adverse effects in adult and pediatric cancer patients treated with chemotherapy are mood alterations and neurocognitive symptoms, such as disruption of memory, impaired attention, concentration, processing speed, and executive function. As a consequence of cancer therapy, these cognitive deficits that occur at any point during or following chemotherapy are called chemotherapy-related cognitive dysfunction or "chemobrain". Notably, such symptoms can be progressive even after cessation of therapy and might significantly compromise the quality of life in affected patients who are unable to return to their prior social and academic level of performance. Trying to unpick the chemobrain’s pathophysiology has become a major challenge since patients undergoing chemotherapy have an increased risk of depression, anxiety, and other mood disorders, all of which can have a negative and interacting effect on cognitive function. The purpose of this review is to define and review what is known about this poorly understood phenomenon and unravel the mysteries of “chemobrain”, and summarize therapeutic avenues.