Pancreatic cancer, as the seventh leading cause of cancer death worldwide, is typically diagnosed at late stages and only 9% of patients survived beyond 5 years. Previous experimental research has suggested that vitamin D and calcium can potentially reduce the risk of pancreatic cancer. Previous animal research has also shown that high serum phosphate level was associated with severe pancreatitis, a strong risk factor for pancreatic cancer. However, results from previous epidemiological studies have varied on the association between vitamin D and pancreatic cancer, and the associations between calcium and phosphate level and pancreatic cancer have seldom been studied. Our study aims to assess the pancreatic cancer occurrence and survival by serum levels of vitamin D, calcium and phosphate. Then, we will investigate whether the effects of vitamin D, calcium and phosphate on pancreatic cancer varies by age, ethnicity, sex, smoking status, diabetes, pancreatitis, BMI, ABO blood type, vitamin D-binding protein (DBP) isoforms, the season of blood drawn and sun exposure. We plan to finish this study within 12 months, including data analysis, manuscript drafting, and presentation of findings. This study will provide a thorough assessment of the role of vitamin D, calcium and phosphate on pancreatic cancer risk and survival individually and combined in one of the largest studies to date. Additionally, the result of this study may provide insights into pancreatic cancer prevention, especially for the risk population such as smokers, people with obesity, people with a high volume of sun exposure, patients with abnormal serum calcium and phosphate levels, and those with vitamin D deficiency or abnormally high vitamin D levels.
