BACKGROUND: Parathyroid hormone (PTH) has been proposed to play a promoting role in carcinogenesis. However, no epidemiologic studies have yet directly investigated its role in colorectal cancer (CRC). METHODS: A case-control study nested within the European Prospective Investigation into Cancer and Nutrition cohort was conducted with 1,214 incident, sporadic CRC cases matched to 1,214 controls. Circulating prediagnostic PTH and 25-hydroxy vitamin D [25(OH)D] concentrations were measured by enzyme-linked immunosorbent assays. Detailed dietary and lifestyle questionnaire data were collected at baseline. Multivariable conditional logistic regression was used to estimate the incidence rate ratio (RR) with 95% confidence intervals (95% CI) for the association between circulating PTH and CRC risk. RESULTS: In multivariate analyses [including adjustment for 25(OH)D concentration] with a priori defined cutoff points, high levels of serum PTH (≥65 ng/L) compared with medium PTH levels of 30-65 ng/L were associated with increased CRC risk (RR = 1.41, 95% CI: 1.03-1.93). In analyses by sex, the CRC risk was 1.77 (95% CI: 1.14-2.75) and 1.15 (95% CI: 0.73-1.84) in men and women, respectively (P(heterogeneity) = 0.01). In subgroup analyses by anatomical subsite, the risk for colon cancer was RR = 1.56, 95% CI: 1.03-2.34, and for rectal cancer RR = 1.20, 95% CI: 0.72-2.01 (P(heterogeneity) = 0.21). Effect modification by various risk factors was examined. CONCLUSIONS: The results of this study suggest that high serum PTH levels may be associated with incident, sporadic CRC in Western European populations, and in particular among men. IMPACT: To our knowledge, this is the first study on PTH and CRC. The role of PTH in carcinogenesis needs to be further investigated.

Original publication

DOI

10.1158/1055-9965.EPI-10-1212

Type

Journal article

Journal

Cancer Epidemiol Biomarkers Prev

Publication Date

05/2011

Volume

20

Pages

767 - 778

Keywords

Case-Control Studies, Cohort Studies, Colorectal Neoplasms, Enzyme-Linked Immunosorbent Assay, European Continental Ancestry Group, Female, Follow-Up Studies, Humans, Incidence, Male, Middle Aged, Nutritional Sciences, Parathyroid Hormone, Prognosis, Prospective Studies, Risk Factors