The Effect of Diet on Breast Cancer Recurrence: The DIANA-5 Randomized Trial.

PURPOSE: The DIANA-5 randomized controlled trial assessed the effectiveness of a diet based on Mediterranean and macrobiotic traditions (macro-Mediterranean diet) in reducing breast cancer recurrence. PATIENTS AND METHODS: The DIANA-5 study involved 1,542 patients with breast cancer at high risk of recurrence because of estrogen receptor-negative cancer, or metabolic syndrome, or high plasma levels of insulin or testosterone. Women were randomly assigned to an active dietary intervention (IG) or a control group (CG). Both groups received the 2007 American Institute for Cancer Research/World Cancer Research Fund recommendations for cancer prevention. The intervention consisted of meetings with kitchen classes, community meals, and dietary recommendations. Recommended foods included whole grain cereals, legumes, soy products, vegetables, fruit, nuts, olive oil, and fish. Foods to be avoided were refined products, potatoes, sugar and desserts, red and processed meat, dairy products, and alcoholic drinks. A compliance Dietary Index was defined by the difference between recommended and discouraged foods. RESULTS: Over the 5 years of follow-up, 95 patients of the IG and 98 of the CG developed breast cancer recurrence [HR = 0.99; 95% confidence interval (CI): 0.69-1.40]. The analysis by compliance to the dietary recommendations (IG and CG together) showed that the women in the upper tertile of Dietary Index change had an HR of recurrence of 0.59 (95% CI: 0.36-0.92) compared with women in the lower tertile. CONCLUSIONS: The DIANA-5 dietary intervention trial failed to show a reduction in breast cancer recurrence, although self-reported diet at year 1 in IG and CG combined showed a protective association with the higher Dietary Index change. See related commentary by McTiernan, p. 931.

Adherence to Dietary Recommendations after One Year of Intervention in Breast Cancer Women: The DIANA-5 Trial.

The Diet and Androgen-5 (DIANA-5) trial aimed at testing whether a dietary change based on the Mediterranean diet and on macrobiotic principles can reduce the incidence of breast cancer (BC)-related events. We analyzed the adherence to the DIANA-5 dietary recommendations by randomization group after 1 year of intervention. We evaluated the association between dietary adherence and changes in body weight and metabolic syndrome (MS) parameters. BC women aged 35-70 years were eligible. After the baseline examinations, women were randomized into an intervention group (IG) or a control group (CG). A total of 1344 BC women (689 IG and 655 CG) concluded the first year of dietary intervention. IG showed greater anthropometric and metabolic improvements compared to CG. These changes were significantly associated with increased adherence to the dietary recommendations. Women who increased recommended foods consumption or reduced discouraged foods consumption showed an Odds Ratio (OR) of 1.37 (0.70-2.67) and 2.02 (1.03-3.98) to improve three or more MS parameters. Moreover, women in the higher category of dietary change showed a four times higher OR of reducing body weight compared to the lower category (p < 0.001). The DIANA-5 dietary intervention is effective in reducing body weight and MS parameters.

Adherence to WCRF/AICR cancer prevention recommendations and metabolic syndrome in breast cancer patients.

Metabolic syndrome (MetS), conventionally defined by the presence of at least three out of five dismetabolic traits (abdominal obesity, hypertension, low plasma HDL-cholesterol and high plasma glucose and triglycerides), has been associated with both breast cancer (BC) incidence and prognosis. We investigated the association between the prevalence of MetS and a score of adherence to the World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) recommendations for the prevention of cancer in a cross-sectional study of BC patients. The DIet and ANdrogen-5 study (DIANA-5) for the prevention of BC recurrences recruited 2092 early stage BC survivors aged 35-70. At recruitment, all women completed a 24-hour food frequency and physical activity diary on their consumption and activity of the previous day. Using these diaries we created a score of adherence to five relevant WCRF/AICR recommendations. The prevalence ratios (PRs) and 95% confidence intervals (CIs) of MetS associated with the number of recommendations met were estimated using a binomial regression model. The adjusted PRs of MetS decreased with increasing number of recommendations met (p < 0.001). Meeting all the five recommendations versus meeting none or only one was significantly associated with a 57% lower MetS prevalence (95% CI 0.35-0.73). Our results suggest that adherence to WCRF/AICR recommendations is a major determinant of MetS and may have a clinical impact.

Metabolic syndrome and breast cancer prognosis.

Metabolic syndrome (MS), conventionally defined by the presence of at least three out of five dysmetabolic traits (abdominal obesity, hypertension, low plasma HDL-cholesterol, high plasma glucose and high triglycerides), has been associated with an increased risk of several age-related chronic diseases, including breast cancer (BC). This may have prognostic implications for BC survivors. 2,092 early stage BC survivors aged 35-70, recruited in eleven Italian centres 0-5 years after surgical treatment (1.74 years on average), were followed-up over 2.8 years on average for additional BC-related events, including BC-specific mortality, distant metastasis, local recurrences and contralateral BC. At recruitment, 20 % of the patients had MS. Logistic regression models were carried out to generate OR and 95 % confidence intervals (CI) for new BC events associated with MS, adjusting for baseline pathological prognostic factors. New BC events occurred in 164 patients, including 89 distant metastases. The adjusted ORs for women with MS versus women without any MS traits were 2.17 (CI 1.31-3.60) overall, and 2.45 (CI 1.24-4.82) for distant metastasis. The OR of new BC events for women with only one or two MS traits was 1.40 (CI 0.91-2.16). All MS traits were positively associated with new BC events, and significantly so for low HDL and high triglycerides. MS is an important prognostic factor in BC. As MS is reversible through lifestyle changes, interventions to decrease MS traits in BC patients should be implemented in BC clinics.