VICTORIA

Colorectal cancer accounts for more than 60,000 new cases and more than 25,000 deaths per year in Germany. The prognosis has particularly improved for earlier stages of the disease. However, detriments in the quality of life often persist.One cause of reduced quality of life in cancer patients might be fatigue. Multiple observational studies have consistently shown that about one-third of colorectal cancer survivors suffer from fatigue not only shortly after diagnosis and initial treatment, but also in the long run. The fatigue syndrome can negatively affect the physical, emotional and cognitive function of the patients. Patients are limited in their ability to cope with their activities of daily living and work.

So far, only non-pharmacologic approaches are effective in alleviating tumor-associated fatigue.

A promising intervention could be to increase the serum 25-hydroxyvitamin D (25(OH)D) status in patients with colorectal cancer and vitamin D deficiency. Results from several observational studies suggest an association between low 25-hydroxyvitamin D levels and fatigue.

The randomized, placebo-controlled, and double-blind VICTORIA study will investigate whether a personalized vitamin D3 supplementation significantly reduces or prevents tumor-related fatigue (primary endpoint). Furthermore, the 25-hydroxyvitamin D level, fatigue sub-domains (physical, emotional, cognitive), quality of life, functional well-being, a probable depression, the infection frequency, and various disease biomarkers are secondary endpoints.

A cohort of overall 456 stage I to III colorectal cancer patients will be recruited in three rehabilitation clinics in Germany. The most important criteria for participation in the trial are: Hospitalization in one of the cooperating rehabilitation clinics for at least three weeks, diagnosis of non-metastatic colorectal cancer, surgical removal of the tumor within the past nine months and vitamin D insufficiency.

Once included, the study participants take vitamin D3 for a total of 12 weeks. The loading dose is determined individually for each patient based on the BMI and the 25-hydroxyvitamin D level at inclusion. A loading dose of 20,000 or 40,000 IU daily during the first 11 days will be taken (In sum, on average approx. 180,000 IU), followed by a maintenance dose of 2,000 IU daily. Overall fatigue along with fatigue sub-domains (physical, emotional, cognitive), the quality of life, the functional well-being and a probable depression are assessed by using validated questionnaire tools (FACIT-F fatigue subscale, EORTC QLQ-FA12, EORTC QLQ-C30, FACIT-F FWB, and GDS-15). The infection frequency is determined by a questionnaire, newly developed for this study. Blood and urine samples will be collected to examine the 25-hydroxyvitamin D level, rule out an overdose and evaluate further biomarkers.