KLK3 and pachyonychia congenita: Since the growth and stage progression of PC tend to be slow, consideration could, therefore, reasonably be given to deferring or even omitting a biopsy in these patients, as long as there is continued monitoring with repetitive PSA sampling, DRE, and/or mpMRI [13, 22, 99, 102, 103, 115] (Fig. 2).