Pre-diagnosis diet and survival after a diagnosis of ovarian cancer

Abstract

Background:The relationship between diet and survival after ovarian cancer diagnosis is unclear as a result of a limited number of studies and inconsistent findings.Methods:We examined the association between pre-diagnostic diet and overall survival in a population-based cohort (n=811) of Australian women diagnosed with invasive epithelial ovarian cancer between 2002 and 2005. Diet was measured by validated food frequency questionnaire. Deaths were ascertained up to 31 August 2014 via medical record review and Australian National Death Index linkage. We conducted Cox proportional hazards regression analysis, controlling for diagnosis age, tumour stage, grade and subtype, residual disease, smoking status, body mass index, physical activity, marital status, and energy intake.Results:We observed improved survival with highest compared with lowest quartile of fibre intake (hazard ratio (HR)=0.69, 95% CI: 0.53–0.90, P-trend=0.002). There was a suggestion of better survival for women with highest compared with lowest intake category of green leafy vegetables (HR=0.79, 95% CI: 0.62–0.99), fish (HR=0.74, 95% CI: 0.57–0.95), poly- to mono-unsaturated fat ratio (HR=0.76, 95% CI: 0.59–0.98), and worse survival with higher glycaemic index (HR=1.28, 95% CI: 1.01–1.65, P-trend=0.03).Conclusions:The associations we observed between healthy components of diet pre-diagnosis and ovarian cancer survival raise the possibility that dietary choices after diagnosis may improve survival.

Vegetable and Fruit Consumption and Prognosis Among Cancer Survivors: A Systematic Review and Meta-Analysis of Cohort Studies

“…Regarding vegetable subgroups, no association between cruciferous vegetable consumption and overall mortality was detected ( Supplemental Figure 1 ). Null results were also found for the intake of other vegetable or fruit subgroups (e.g., green leafy, and yellow and red vegetables, and citrus fruit) ( 59 – 62 ).…”

“…The 4 meta-analyzed studies on ovarian cancer patients ( 59 – 62 ) showed an inverse association between total vegetable and total fruit intake before diagnosis and overall mortality (HR: 0.78; 95% CI: 0.66, 0.91 and HR: 0.82; 95% CI: 0.70, 0.96, respectively) ( Figure 3 A and B ). Although the results are significant, the prediction interval of both meta-analyses will be expected to be outside the protective HR range in 95% of all the population.…”

“…Almost identical protective effects were found with a higher adherence to the Healthy Eating Index ( 60 ). However, the results for the relations between vegetable and fruit subgroup intakes and ovarian cancer prognosis were inconclusive ( 59 – 62 ). Similarly, null results were described between vegetable and fruit intake and incident ovarian cancer risk in the WCRF/AICR report ( 65 ).…”

Pre-diagnosis consumption of preserved vegetables and prognosis of invasive oesophageal squamous cell carcinoma: a prospective cohort study in one high-risk area in China

“… 14 Pre-diagnosis food intake also affected the prognosis of invasive ovarian cancer patients: high consumption of green leafy vegetables was correlated with a 30% reduced risk of death, high consumption of fish was associated with a 26% reduced risk of death, high intake of fibre was associated with a 31% reduced risk of death, but a high glycaemic index was associated with an increased risk of death (HR 1.28: 95% CI 1.01, 1.65). 15 However, the dietary effects on ESCC survival has been less well reported. ESCC is the main pathological type of EC in China and the composition of the Chinese diet is different compared with Western diets.…”

Using ‘Big Data’ to explore unanswered questions in ovarian cancer epidemiology

“…One study suggested women who were inactive before diagnosis had particularly poor survival if they were also current or former smokers (109). Some studies have also reported poorer survival associated with certain features of diet (110)(111)(112), and with lower serum 25hydroxyvitamin D levels (113). At least some of these associations relate to pre-diagnosis exposure, which is obviously not retrospectively modifiable by the patient.…”