Assessment Of Ki67 In Relation To Radiotherapy (Rt) Fractionation And Prognosis In The Chhip (Cruk/06/016) Trial.

98Background: A uniform fractionation schedule is used to deliver external beam RT for localised prostate tumours Individualising fractionation according to tumour biology may improve outcomes. In addition recurrence rates after RT vary considerably and better prognostic markers are needed to guide treatment choices. This study aims to identify if the cell proliferation marker Ki67 predicts response to RT fractionation in CHHiP, a randomised trial of 3 RT fractionation schedules. It also aims to identify if Ki67 predicts prognosis. Methods: A matched case:control study design was used, patients with biochemical or clinical failure u003e 2 years after RT (BCR) were matched to patients without recurrence according to established prognostic factors (Gleason score, PSA, Tumour-stage) and fractionation schedule. Immunohistochemical (IHC) staining of diagnostic biopsy sections was carried out using the MIB1 Ki67 antibody. Two independent investigators scored Ki67 using the unweighted global method (1) to derive a m...