KLK3 and pure red-cell aplasia: Of the 713 PrCa cases, 40 interval cancers occurred in the 17,890 men with PSA < 3 ng/ml, with an incidence rate of 2.2 per 1000 man-years, which is dramatically lower than 240.6 per 1000 based on the finding of 584 screen-detected and 89 interval cancers in 2797 men with PSA ≥ 3 ng/ml.