KLK3 and prostate cancer: However, in a recent reevaluation of these patients, de Vos II and colleagues reported the long-term results (21 years later) of PSA screening showing that after 10 to 12 years, the impacts of these recommendations are evident and patients with 55 to 69 years old from the non-screening group had worse outcomes with higher rates of metastasis and prostate cancer-specific mortality (39).