Specifically Choy et al. [2] reported that an increase in the percentage of tumor in radical prostatectomy (RPx) samples that is GP4 or greater is associated with an increase in biochemical recurrence (BCR)—ranging from 16% BCR in men where GP4 content was 1–20% to 68% BCR where GP4 was >70% [2]. Here, BCR is linked to neoplasm.