(Ivanhoe Newswire) – Breast cancer survivors may have problems with certain mental abilities several years after treatment, according to this study. This could occur regardless of whether they were treated with chemotherapy plus radiation or radiation only. This study suggests there may be a common and treatment-specific way that cancer therapies negatively affect cancer survivors’ mental abilities.

Previous research suggests that chemotherapy can cause problems with memory and concentration in breast cancer survivors. To compare the effects of different types of cancer treatment on such mental abilities, Paul Jacobsen, PhD, of the Moffitt Cancer Center and Research Institute in Tampa, and his colleagues examined 62 breast cancer patients treated with chemotherapy plus radiation, 67 patients treated with radiation only, and 184 women with no history of cancer. Study participants completed neuropsychological assessments six months after completing treatment and again 36 months later, which is further out from the end of treatment than most previous studies of this type.

The study confirmed that chemotherapy can cause cognitive problems in breast cancer survivors that persist for three years after they finish treatment. In addition, the investigators found that breast cancer survivors who had been treated with radiation (and not chemotherapy) often experienced problems similar to those in breast cancer survivors treated with both chemotherapy and radiation. They did not find that hormonal therapy (such as tamoxifen) caused cognitive difficulties.

"These findings suggest that the problems some breast cancer survivors have with their mental abilities are not due just to the administration of chemotherapy," Dr. Jacobsen was quoted as saying. "Our findings also provide a more complete picture of the impact of cancer treatment on mental abilities than studies that did not follow patients as long or look at mental abilities in breast cancer survivors who had not been treated with chemotherapy."

SOURCE: CANCER, published online December 2011