slow recruitment, patients lost to follow-up due to Covid-19 pandemic.

Different studies have shown that a deficiency in vitamin D (≤20ng/mL) results in higher rates in morbidity and mortality rates in cancer patients. Clinical studies investigated and demonstrated altered vitamin d tissue in pancreatic cancer. But there is no prospective study evaluating the beneficiary effects of oral supplementation of vitamin d in altered vitamin d tissue from pancreatic cancer. We want to examine the effect of a high dose vitamin D3 therapy vs. a standard base dose vitamin D3 therapy in pancreas cancer patients with a vitamin D deficiency. In case of benefit in our results we could implement vitamin D3 as a supportive standard therapy in pancreatic cancer patients.

Inclusion Criteria:

both sexes

• vitamin D deficiency(≤20ng/ml)
• patients>18 years of age
• pancreatic cancer
• surgical intervention/non-surgical intervention
• signed written informed consent

Exclusion Criteria:

• patients<18 years of age
• pregnancy
• contraindication for oral vitamin D intake
• hypercalcemia (> 2.65 mmol/l total calcium and/or > 1.35 mmol/l ionized calcium at screening)
• other ongoing vitamin D conducted trial
• known kidney stones, active tuberculosis or sarcoidosis (in the last 12 months)
• metastasized pancreatic cancer
• normal vitamin D serum levels
• missing written informed consent