Study Protocol
Clinical and demographic characteristics of the participants in both groups such as education, age, family history of prostate cancer, marital status, surgeries, systemic diseases, smoking, alcohol use, and vitamin D use were recorded by face-to-face interviews. Serum prostate-specific antigen (PSA) levels of all cases in diagnosis and disease stages were recorded by reviewing their medical records because the diagnosis date of the cases, the time of cytological evidence, was accepted as the reference. Controls were matched in the reference month in the same month. The measured PSA results were collected by reviewing medical records of the controls.