Conclusion
An association was found between the reducing M/C ratio or morning
urinary melatonin-sulfate levels and the risk of prostate cancer. We
also found that patients whose M/C ratios and PSA levels beyond 10 ng/mL
were low had much higher risk of advanced (end-stage) disease and
prostate cancer. Due to this cross-sectional and case-control nature of
the study, it was not possible to establish an accurate causal
relationship between prostate cancer risk and the urinary M/C ratio.
These results can be confirmed with some larger prospective cohort
studies.