This observational study recruited participants with primary prostate cancer (cases) and those with benign hyperplasia (controls) before the surgery. Data on the outcomes of the surgery including the results of the biopsy investigation were collected. Blood samples were collected before the surgery in context of routine blood investigations. Blood plasma samples collected on ethylenediaminetetraacetic acid (EDTA) were used to measure concentrations of free choline, betaine, dimethylglycine, folate forms, S-adenosylhomocysteine, S-adenosylmethionine, homocysteine, cystathionine, and methylmalonic acid (MMA). Data on serum concentrations of prostate specific antigen (PSA) and the tumor grade and classification (Gleason Score system) were collected. The associations between the plasma concentrations of the metabolites and PSA or the Gleason score were studied. The concentrations of the metabolic markers were compared between the cases and the controls according to the age of the participants.
