Chang WP, et al. - Via involving a total of 12 study articles, researchers sought to understand the changes in the sleep quality of women with breast cancer during their treatment period. According to findings, in the initial months after the beginning of treatment, patients experienced better sleep quality. Their sleep quality, however, declined from 4 months to about 1 year after the start of treatment compared with the sleep quality prior to treatment and continued to decline rather than improve during the follow-up period.