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

Abstract

ObjectiveTo investigate the prognostic effect of pre-diagnosis preserved vegetable consumption on oesophageal squamous cell carcinoma (ESCC) in Yanting County, China.MethodsThis prospective cohort study enrolled consecutive patients with ESCC. The pre-diagnosis diet consumption data were collected using a food frequency questionnaire at baseline. Preserved vegetable consumption was categorized into two groups: < 1/week and ≥1/week. Kaplan–Meier survival curve analysis with a log-rank test and a Cox proportional hazard regression model analysis were undertaken to compare the two consumption groups.ResultsThe study enrolled 185 patients (121 males and 64 females) with ESCC. Patients consuming preserved vegetables ≥1/week had a median survival time of 41 months, but patients consuming preserved vegetables <1/week did not achieve a median survival time. The adjusted hazard ratio (HR) for an intake of ≥1/week was 1.58 (95% confidence interval [CI] 1.01, 2.47). Among ‘ever smokers’, the HR increased to 2.04 (95% CI 1.10, 3.77) and among ‘ever alcohol drinkers’, the HR increased to 2.50 (95% CI 1.33, 4.73). Among ‘never smokers’ or ‘never alcohol drinkers’, no significant association was observed.ConclusionA high consumption of preserved vegetables was associated with a poorer prognosis among patients with ESCC.

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

“…There was no association between prediagnosis green vegetable intake and overall mortality in pancreatic cancer patients ( 42 ). A Chinese study reported that the higher consumption of fermented preserved vegetables before diagnosis significantly correlated with a higher risk of all-cause mortality in esophagus cancer patients ( 40 ).…”

“…The main cause for this classification was the concern of changes in exposure status among patients. In addition, minor reasons reducing the quality of studies were observed: bias due to confounding ( 40 , 41 , 57 ), bias in classification of exposures ( 39 , 40 , 42 , 47 , 48 , 56 ), and bias in selection of the reported results ( 36 , 39 , 41 , 42 , 57 , 61 ) ( Supplemental Table 7 ). More details about the items considered in both the ROBINS-E and the STROBE-nut scale are provided as supplementary material ( Supplemental Tables 8 and 9 , respectively).…”

“…There are few studies on prognosis in digestive tract cancer survivors [esophagus ( 40 ), stomach ( 37 , 44 ), pancreas ( 42 ), and colorectum ( 41 , 45 – 47 )], suggesting basically null results. However, the lowest consumption of green leafy vegetables (almost never compared with almost every day) was directly associated with a higher all-cause mortality in male colorectal cancer patients, particularly with colon cancer ( 41 ).…”

“…These results are similar to those reported for the incidence of upper gastrointestinal cancer, but not prostate cancer ( 81 ). The consumption of ≥1 serving/wk (≥70 g/wk) of fermented preserved vegetables was associated with a higher all-cause mortality in all patients, in ever smokers (smoking >100 cigarettes or equivalent use of pipes in their lifetime) and in ever alcohol drinkers (individuals that drank alcohol at least once per month) with esophagus cancer, but not in those who have never smoked or drunk ( 40 ). Likewise, the consumption of salt-preserved foods correlates with a higher risk incidence of gastric and nasopharynx cancer ( 65 ).…”

Dietary factors and risk of mortality among patients with esophageal cancer: a systematic review

“…After removal of 4215 duplicates, 3795 potentially eligible records were left, of which 3677 were excluded after reviewing the titles and abstracts. Finally, 15 eligible cohort studies [12][13][14][15][23][24][25][26][27][28][29][30][31][32][33] containing 6826 esophageal cancer patients were identified through full text review of 118 studies. The most common reasons for exclusion were study designs, lack of data on dietary exposure and no outcomes of interest.…”