IGF1 and breast cancer: The finding that serum IGF-I was not associated with breast cancer risk in postmenopausal women is consistent with data from other prospective studies (Hankinson et al, 1998; Kaaks et al, 2002; Krajcik et al, 2002; Toniolo et al, 2000; Keinan-Boker et al, 2003; Grønbæk et al, 2004).