KLK3 and cancer: Of the studies that considered progression through stages or grades of cancer, Heijnsdijk et al23 found that PSA + PHI testing saves costs compared with PSA testing alone and results in the same QALYs23 and Karlsson et al27 estimated an incremental cost-effectiveness ratio (ICER) of €5663 for screening using Stockholm3 when PSA values were above 2 ng/mL compared with PSA alone.