According to a new study published in January 2007 issue of CANCER, chemotherapy is linked with short-term structural changes in the cognitive areas of the brain. In CANCER (http:www.interscience .wiley.com/cancer-newsroom), a peer-reviewed journal of the American Cancer Society, the researchers of the study have revealed that within 12 months of receiving adjuvant chemotherapy, significant regions of the brain associated with memory, analysis and other cognitive functions were significantly smaller in breast cancer patients who received chemotherapy than those who did not. Within four years after treatment, however, there were no differences in these same regions of the brain.

While the development of chemotherapy has had substantial and beneficial impact on cancer survival rates, it is also linked to significant short- and long-term adverse effects. Gastrointestinal complaints, immunosuppression, and painful mucositis, for example, are the immediate risks of the treatment.

Patients receiving chemotherapy have also long complained of problems with memory, problem-solving and other cognitive abilities. Although chemotherapy was thought not to affect brain cells due to the blood-brain barrier, recent clinical studies have confirmed declines in cognitive functions in patients receiving chemotherapy. Animal studies have shown physical changes in the brain and in neurons caused by chemotherapy drugs. In human studies, however, the little data that is available is only available through imaging and is not consistent in the long-term. In addition, lack of controls in studies makes it difficult discern cancer- versus drug-effects.