This project hypothesises that higher plasma vitamin D concentrations are associated with decreased risk of recurrence and better quality of life in patients with non-muscle invasive bladder cancer.
Patients diagnosed with non-muscle invasive bladder cancer (NMIBC) are at high risk of tumour recurrence. After diagnosis, they are subjected to a burdensome treatment and follow-up program. This may have a great impact on their quality of life. Whether lifestyle-related factors can reduce risk of recurrence and improve quality of life in this patient group is largely unknown. High versus low vitamin D concentrations have been associated with lower risk of recurrence and mortality and better quality of life in patients with several cancer types. However, studies in patients with NMIBC are scarce.
Our hypothesis is that higher plasma vitamin D concentrations are associated with decreased risk of recurrence and better quality of life in patients with NMIBC.
We will investigate plasma vitamin D concentrations at 3 and 15 months after diagnosis in relation to risk of recurrence and quality of life in patients with NMIBC.
We will also examine associations of genetic variants in vitamin D-related genes with recurrence risk. In addition, we will explore whether associations of vitamin D concentrations with risk of recurrence and quality of life differ for patients with different clinical characteristics, lifestyle factors or genetic variants of vitamin D-related genes.
For this proposed project, we will use data from our Dutch prospective multicenter cohort UroLife. From May 2014-April 2021, patients newly diagnosed with NMIBC in 22 hospitals in the Netherlands were included.
Plasma samples and questionnaire data are available for 1,278 patients at 3 months and for 1,022 patients at 15 months after diagnosis.
Plasma samples will be analysed for vitamin D. Genetic variants in vitamin D-related genes have already been determined.
Questionnaires include data on sociodemographic factors, smoking, body weight, physical activity, diet, dietary supplement use, comorbidity and quality of life.
Data on molecular subtypes of T1 tumours are available at the start of the project. Follow-up data on recurrence and treatment are available for 906 patients and will be updated by the Netherlands Cancer Registry for all 1,278 patients.
We will conduct statistical analyses to evaluate the association of season-adjusted plasma concentrations of vitamin D and vitamin D-related polymorphisms with risk of recurrence. We will also statistically analyse the association of plasma vitamin D concentrations with quality of life.
In addition, we will explore whether associations are different for patients who differ in clinical characteristics (tumour stage, molecular subtype, treatment) and lifestyle factors (e.g. smoking, BMI, physical activity) or in patients with different genetic variants in vitamin D-related genes.
This proposed project will provide important insights in whether higher plasma vitamin D concentrations are associated with reduced risk of recurrence and improved quality of life in patients with NMIBC.
Currently, only 12% of Dutch patients with NMIBC uses vitamin D supplements which can increase plasma vitamin D concentrations.
Results of this project may contribute to intervention studies and, ultimately, to evidence-based advice on vitamin D supplementation to reduce recurrence risk and improve quality of life in this patient group.
This grant enables us to investigate the relation between circulating vitamin D concentrations and risk of recurrence and quality of life in patients with non-muscle invasive bladder cancer. Results of this project may ultimately contribute to evidence-based advice on vitamin D supplementation to reduce recurrence risk and improve quality of life in this understudied patient group.
Dr Alina Vrieling
