I'm interested in this position virectin comments This current study was based on information from the Childhood Cancer Survivor Study, a cohort study of five-year survivors.  These survivors came from 21 institutions who were under the age of 21 when they were diagnosed with cancer between 1970 and 1986.  This included 3,531 sexually active female survivors (age 18,39) along with a control group of 1,366 female siblings.