KLK3 and prostate cancer: PSA measurement was introduced in 1987 to verify the response to prostate cancer treatment, but was soon adopted for prostate cancer screening too [29,30] and after widespread use of PSA as a screening test, a dramatic rise in incidence was reported from 1989 to 1992 and from 1995 this rise continued with a slight slope until 2001 and after that has fluctuated year to year revealing changes in screening practices [31].