KLK3 and neoplasm: conducted autopsy for 14 patients who died of PCa, and found that 12 of 14 patients presented diffuse osteoblastic metastases; further immunostaining of the osseous metastases revealed that averagely 75% of tumor cells at metastatic sites expressed immunoreactive PSA, and over 40% of the patients had over 90% of tumor cells at metastatic sites expressing immunoreactive PSA (20).