DietCompLyf Study – How Diet and Lifestyle affect breast cancer recurrence and survival

Researchers: Dr Anthony Leathem and Dr Miriam Dwek

Location: University of Westminster, London

Dates:  1997 – 2014     Status: Complete

Funding: £5,137,022

Research Theme: Prevention

Aims

Our DietCompLyf (DCL) observational study at the University of Westminster, London, initiated by our founder Dr Anthony Leathem and led by Dr. Miriam Dwek, aimed to explore the effects of dietary phytoestrogens on breast cancer recurrence and patient survival.

Background

Diet has been found to influence hormone production and metabolism which in turn could affect the incidence of hormone-related cancers. Phytoestrogens are plant-based compounds that are similar to the hormone oestrogen and have a wide range of metabolic effects. Consumption of soy-containing foods, known to be rich in phytoestrogens, is thought to be one of the protective factors against breast cancer in Asian populations. Although there is mounting evidence of the positive influence of phytoestrogens on primary breast cancer risk, very little research had been carried out in humans as to the effects of phytoestrogens on secondary breast cancer recurrence and survival.

The DietCompLyf study was supported by the National Cancer Research Network and aimed to enrol over 3,300 breast cancer patients from 56 centres across the UK. Each patient participated from one year post-diagnosis of primary breast cancer and was on active follow-up for 5 years.

Data collected annually included blood and urine samples, which will now form the DietCompLyf Biobank, and detailed data including 7 day food diaries, food frequency questionnaires (FFQ), lifestyle and general health questionnaires.

The study aimed to primarily explore the effect of dietary phytoestrogen consumption, but the effects of other diet and lifestyle practices and the use of complementary treatments were also investigated to identify differences between UK patients who develop secondary spread and those who do not.

Potential benefit for patients

Identifying specific diet and lifestyle factors that might reduce the risk of secondary breast cancer recurrence could become evidence-based advice for breast cancer patients. Reducing the risk of recurrence or even being able to actively prevent recurrence through lifestyle choices would greatly improve patient outcome.

Project Results and Impact

The resulting resource of linked biological samples and diet and lifestyle data across a longitudinal study of 5 years comprise one of the largest collections of its kind in the UK.

Samples from the biobank have also been shared with the Breast Cancer Association Consortium (BCAC), a forum of international investigators who are combining information from many studies to identify gene mutations that give rise to breast cancer.

Project results have included:

• Over 46,000 diet and lifestyle questionnaires have been collected

We are awaiting the final data analysis publication, but preliminary analyses on a subset of patients suggest:

• There is no link between the amount of phytoestrogens eaten during the year prior to diagnosis and tumour characteristics or patient outcome/prognosis. Showing no links is important data as this means that active alterations in phytoestrogen intake prior to primary diagnosis are not required as they do not improve prognosis.
• After diagnosis, consumption of fruit, veg, wholegrains and lean protein increased while high fat and high sugar food intake decreased.
• Adherence to all the World Cancer Research Fund guidelines for reducing cancer risk is often low. Participants that were longer-educated showed better adherence to the guidelines. The guidelines for cancer prevention are evidence-based and can make a difference. This result suggests that in our study either people were not aware of the recommendations, or they found them difficult to adhere to.

“Our Diet & Lifestyle study is the first in the world to look at the association between the recurrence of breast cancer and the intake of plant oestrogen-like foods.”

Dr Miriam Dwek

Publications

DCL study results:

The DietCompLyf study: a prospective cohort study of breast cancer survival and phytoestrogen consumption. Swann R, Perkins KA, Velentzis LS, Ciria C, Dutton SJ, Mulligan AA, Woodside JV, Cantwell MM, Leathem AJ, Robertson CE, Dwek MV. Maturitas. 2013 Jul;75(3):232-40.

Significant changes in dietary intake and supplement use after breast cancer diagnosis in a UK multicentre study. Velentzis LS, Keshtgar MR, Woodside JV, Leathem AJ, Titcomb A, Perkins KA, Mazurowska M, Anderson V, Wardell K, Cantwell MM. Breast Cancer Res Treat 2011 Jul;128(2):473-82.

Adherence to WCRF/AICR guidelines for cancer prevention in participants of the DietCompLyf breast cancer survival study. Brennan et al (conference poster).

Associated publications:

Lignans and breast cancer risk in pre- and post-menopausal women: meta-analyses of observational studies. Velentzis LS, Cantwell MM, Cardwell C, Keshtgar MR, Leathem AJ, Woodside JV. Br J Cancer 2009 May 5;100(9):1492-8.

Dietary patterns and breast cancer risk: a systematic review and meta-analysis. Sarah F Brennan, Marie M Cantwell, Chris R Cardwell, Louiza S Velentzis, Jayne V Woodsid, The American Journal of Clinical Nutrition, Volume 91, Issue 5, May 2010, Pages 1294–1302.

Do phytoestrogens reduce the risk of breast cancer and breast cancer recurrence? What clinicians need to know. Velentzis LS, Woodside JV, Cantwell MM, Leathem AJ, Keshtgar MR.Eur J Cancer. 2008 Sep;44(13):1799-806. doi: 10.1016/j.ejca.2008.05.019. Epub 2008 Jul 7.