TY - JOUR
T1 - Dietary fat reduction and breast cancer outcome
T2 - Interim efficacy results from the women's intervention nutrition study
AU - Chlebowski, Rowan T.
AU - Blackburn, George L.
AU - Thomson, Cynthia A.
AU - Nixon, Daniel W.
AU - Shapiro, Alice
AU - Hoy, M. Katherine
AU - Goodman, Marc T.
AU - Giuliano, Armando E.
AU - Karanja, Njeri
AU - McAndrew, Philomena
AU - Hudis, Clifford
AU - Butler, John
AU - Merkel, Douglas
AU - Kristal, Alan
AU - Caan, Bette
AU - Michaelson, Richard
AU - Vinciguerra, Vincent
AU - Del Prete, Salvatore
AU - Winkler, Marion
AU - Hall, Rayna
AU - Simon, Michael
AU - Winters, Barbara L.
AU - Elashoff, Robert M.
PY - 2006/12/20
Y1 - 2006/12/20
N2 - Background: Preclinical and observational studies suggest a relationship between dietary fat intake and breast cancer, but the association remains controversial. We carried out a randomized, prospective, multicenter clinical trial to test the effect of a dietary intervention designed to reduce fat intake in women with resected, early-stage breast cancer receiving conventional cancer management. Methods: A total of 2437 women were randomly assigned between February 1994 and January 2001 in a ratio of 40 : 60 to dietary intervention (n = 975) or control (n = 1462) groups. An interim analysis was performed after a median follow-up of 60 months when funding for the intervention ceased. Mean differences between dietary intervention and control groups in nutrient intakes and anthropometric variables were compared with t tests. Relapse-free survival was examined using Kaplan-Meier analysis, stratified log-rank tests, and Cox proportional hazards models. Statistical tests were two-sided. Results: Dietary fat intake was lower in the intervention than in the control group (fat grams/day at 12 months, 33.3 [95% confidence interval {CI} = 32.2 to 34.5] versus 51.3 [95% CI = 50.0 to 52.7], respectively; P<.001), corresponding to a statistically significant (P = .005), 6-pound lower mean body weight in the intervention group. A total of 277 relapse events (local, regional, distant, or ipsilateral breast cancer recurrence or new contralateral breast cancer) have been reported in 96 of 975 (9.8%) women in the dietary group and 181 of 1462 (12.4%) women in the control group. The hazard ratio of relapse events in the intervention group compared with the control group was 0.76 (95% CI = 0.60 to 0.98, P = .077 for stratified log rank and P = .034 for adjusted Cox model analysis). Exploratory analyses suggested a differential effect of the dietary intervention based on hormonal receptor status. Conclusions: A lifestyle intervention reducing dietary fat intake, with modest influence on body weight, may improve relapse-free survival of breast cancer patients receiving conventional cancer management. Longer, ongoing nonintervention follow-up will address original protocol design plans, which called for 3 years of follow-up after completion of recruitment.
AB - Background: Preclinical and observational studies suggest a relationship between dietary fat intake and breast cancer, but the association remains controversial. We carried out a randomized, prospective, multicenter clinical trial to test the effect of a dietary intervention designed to reduce fat intake in women with resected, early-stage breast cancer receiving conventional cancer management. Methods: A total of 2437 women were randomly assigned between February 1994 and January 2001 in a ratio of 40 : 60 to dietary intervention (n = 975) or control (n = 1462) groups. An interim analysis was performed after a median follow-up of 60 months when funding for the intervention ceased. Mean differences between dietary intervention and control groups in nutrient intakes and anthropometric variables were compared with t tests. Relapse-free survival was examined using Kaplan-Meier analysis, stratified log-rank tests, and Cox proportional hazards models. Statistical tests were two-sided. Results: Dietary fat intake was lower in the intervention than in the control group (fat grams/day at 12 months, 33.3 [95% confidence interval {CI} = 32.2 to 34.5] versus 51.3 [95% CI = 50.0 to 52.7], respectively; P<.001), corresponding to a statistically significant (P = .005), 6-pound lower mean body weight in the intervention group. A total of 277 relapse events (local, regional, distant, or ipsilateral breast cancer recurrence or new contralateral breast cancer) have been reported in 96 of 975 (9.8%) women in the dietary group and 181 of 1462 (12.4%) women in the control group. The hazard ratio of relapse events in the intervention group compared with the control group was 0.76 (95% CI = 0.60 to 0.98, P = .077 for stratified log rank and P = .034 for adjusted Cox model analysis). Exploratory analyses suggested a differential effect of the dietary intervention based on hormonal receptor status. Conclusions: A lifestyle intervention reducing dietary fat intake, with modest influence on body weight, may improve relapse-free survival of breast cancer patients receiving conventional cancer management. Longer, ongoing nonintervention follow-up will address original protocol design plans, which called for 3 years of follow-up after completion of recruitment.
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U2 - 10.1093/jnci/djj494
DO - 10.1093/jnci/djj494
M3 - Article
C2 - 17179478
AN - SCOPUS:33845894946
VL - 98
SP - 1767
EP - 1776
JO - Journal of the National Cancer Institute
JF - Journal of the National Cancer Institute
SN - 0027-8874
IS - 24
ER -