The tumor cells fail to form complete glands and aggregate in poorly formed, disrupted glands, merged glands and cribriform patterns that are less distinctly demarcated from the stroma.[10,11] This suggests that cells with a Gleason pattern 4 leak PSA through the disrupted cell membrane while cells with Gleason pattern 3 do not, or at least not to the same extent. Here, KLK3 is linked to neoplasm.