Date of Award

Spring 2020

Document Type

Open Access Thesis


Epidemiology and Biostatistics

First Advisor

Susan Steck


Prostate cancer is the most commonly diagnosed cancer among men in the United States. Despite improvements in screening, diagnostic methods, and treatment, African-American men have an increased risk of total and aggressive prostate cancer. In recent years, a growing body of evidence linking biomarkers of calcium and parathyroid hormone (PTH) to prostate cancer development has emerged. Circulating calcium, phosphorus, and PTH are homeostatically related. Prior studies linking prostate cancer and circulating calcium and PTH have produced inconclusive results, and no studies have examined the association between serum phosphorus and prostate cancer. The present study examined the relationship between circulating calcium, phosphorus, and PTH and aggressive prostate cancer in a sample of African-American and European American men in the North Carolina-Louisiana Prostate Cancer Project (PCaP). Serum calcium was associated with a modest decreased odds of aggressive prostate cancer though the confidence interval lacked precision. There was suggestion of effect modification by overweight/obesity status, though these results were not statistically significant. High serum phosphorus was associated with an increased odds of aggressive prostate cancer across various categorization approaches. There was a slight inverse association between aggressive prostate cancer and PTH, and this association was modified by number of comorbidities. The joint effects of circulating calcium, phosphorus, PTH, and 25(OH)D were observed. Across categories of low and high analytes, serum phosphorus was associated with increased odds of aggressive prostate cancer. Higher serum phosphorus may reflect high dietary intake of phosphorus and a less healthy diet overall. A previous study found a positive association between higher dietary phosphorus intake and aggressive prostate cancer risk, corroborating our results. Future studies are warranted to more thoroughly examine the role of serum phosphorus in prostate cancer progression.


© 2020, Brittany Crawford