JU INSIGHT: Post-diagnostic Zinc Supplement Use and Prostate Cancer Survival in Nonmetastatic Prostate Cancer
By: Yiwen Zhang, MS, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; Konrad H. Stopsack, MD, MPH, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; Kana Wu, MD, PhD, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; Mingyang Song, MD, ScD, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, Massachusetts General Hospital and Harvard Medical School, Boston; Lorelei A. Mucci, MPH, ScD, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; Edward Giovannucci, MD, ScD, Harvard T. H. Chan School of Public Health, Boston, Massachusetts | Posted on: 17 Mar 2023
Zhang Y, Stopsack KH, Wu K, Song M, Mucci LA, Giovannucci E. Post-diagnostic zinc supplement use and prostate cancer survival among men with nonmetastatic prostate cancer. J Urol. 2023;209(3):549-556.
Study Need and Importance
Zinc supplementation is hypothesized to have therapeutic potential against prostate cancer. Both biological and experimental evidence supports restoration of normal zinc levels in malignant prostate cells may be a promising prostate cancer treatment, yet the influence of zinc supplementation on prostate cancer survival in a human population remains unknown. In this study, we prospectively assessed post-diagnostic zinc supplementation in relation to prostate cancer survival (lethal prostate cancer and all-cause mortality) among 5,788 men with nonmetastatic prostate cancer in the Health Professionals Follow-up Study (1986-2019).
What We Found
We observed an inverse association between post-diagnostic zinc supplement use and prostate cancer survival. Compared to nonusers, post-diagnostic supplement use was associated suggestively with a lower risk of lethal prostate cancer and significantly with all-cause mortality. The inverse association was mostly observed among men who used post-diagnostic zinc supplements of 1-24 mg/d, while higher dosage did not show a lower risk.
Zinc supplement dosage was predefined on questionnaires, and we were unable to accurately calculate total zinc supplementation from multivitamin and individual zinc supplement. However, our stratified analysis showed similar inverse association in both multivitamin users and nonuser groups. Second, we did not have information on drugs and foods that can block zinc absorption or biological measures of zinc concentration in prostate cancer tissue. Third, potential measurement errors in the self-reported questionnaires exist. Finally, as our cohort consists of health professionals who were mostly well-nourished, our results may not be generalizable to different ethnic groups, or to populations with different underlying nutrient status.
Interpretation for Patient Care
Post-diagnostic low-dose zinc supplement use among nonmetastatic prostate cancer patients was associated with lower risk of lethal prostate cancer and all-cause mortality. A potential benefit of low-dose post-diagnostic zinc supplement for prostate cancer survival merits further study.