Ki67 labelling was significantly higher in ISUP 1 diagnostic biopsies from patients identified with grade 3 or 4 tumours after prostatectomy than in cases that remained as grade 1 also in the prostatectomy samples (6.0 ± 2.5, n = 7 versus 3.6 ± 1.5, n = 9, p < 0.05, respectively; mean ± SD, t‐test). Here, MKI67 is linked to neoplasm.