TIAM1 and prostate cancer: To analyse potential associations between the extent of Tiam1 overexpression in prostate cancer and different clinico-pathological factors (age, preoperative PSA, LVI, BVI, PNI, pT, pN, GS, and disease recurrence) Tiam1 immunoreactive ratios (e.g. Tiam1 expression levels in prostate cancer relative to those in the corresponding benign secretory epithelial cells), were dichotomised into two categories (<3.5-fold vs ⩾3.5-fold).