Studies investigating the association of food and nutrient consumption with the risk of urothelial cell carcinoma ( UCC ) have produced mixed results.
Researchers used three common dietary scores, the Mediterranean Diet Score ( MDS ), the Alternate Healthy Eating Index 2010 ( AHEI-2010 ), and the Dietary Inflammatory Index ( DII ) to assess the evidence of an association between diet and the risk of urothelial cell carcinoma.
Over a median follow-up time of 21.3 years, 379 incident urothelial cell carcinoma cases were diagnosed.
Dietary scores were calculated using data from a 121-item food frequency questionnaire administered at baseline.
None of the dietary scores was associated with the risk of urothelial cell carcinoma overall.
A healthier diet was found to be inversely associated with the risk of invasive ( MDS: HR=0.86, 95% CI: 0.74-1.00, metascore: HR=0.84, 95% CI: 0.71-0.98 ), but not superficial disease ( heterogeneity between subtypes p=0.04 and p=0.03, respectively ).
Results were consistent but weaker for DII and AHEI-2010.
Researchers found some evidence of effect modification by smoking, in particular for the metascore ( Current: HR=0.77, 95% CI: 0.58-1.01, Former: HR=0.77, 95% CI: 0.64-0.92, Never: HR=1.01, 95% CI: 0.81-1.26, p for heterogeneity=0.05 ).
A healthy diet may be protective against the risk of invasive, but not superficial, urothelial cell carcinoma.
Promoting healthy dietary habits may help lower the risk of invasive urothelial cell carcinoma, especially for current and former smokers. ( Xagena )
Dugué PA et al, Int J Cancer 2016; Epub ahead of print