title: Pre-treatment proliferation and the outcome of conventional and accelerated radiotherapy.
abstract: This study investigated the influence of pre-treatment proliferation characteristics, assessed by Ki-67 staining, in patients treated in the CHART trial of accelerated radiotherapy in head and neck cancer. Histological material from 402 patients was collected and stained for the presence and pattern of Ki-67 staining. Locoregional control and overall survival were the main clinical endpoints. Increasing Ki-67 positivity was associated with decreasing differentiation (P < 0.001) and increasing N-stage (P < 0.004). Increasing N-stage was also associated with the progression of proliferation pattern from marginal to random (P < 0.001). Using a multivariate model, a trend was seen towards a greater benefit from CHART in the lower Ki-67 tumours (P = 0.08); this became significant by pooling the low and intermediate Ki-67 groups in comparison with the high Ki-67 group (P = 0.032). Tumours with marginal proliferation pattern showed a lower hazard ratio with CHART versus conventional for locoregional control (P = 0.005). The data presented in this study do not support that a high pre-treatment Ki-67 is associated with a therapeutic benefit from accelerated radiotherapy.
authors.affiliation: Gray Cancer Institute, Mount Vernon Hospital, Northwood, Middlesex HA6 2JR, UK. george.wilson@beaumont.edu
authors.forename: George D
authors.initials: GD
authors.lastname: Wilson
authors.forename: Michele I
authors.initials: MI
authors.lastname: Saunders
authors.forename: Stanley
authors.initials: S
authors.lastname: Dische
authors.forename: Frances M
authors.initials: FM
authors.lastname: Daley
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Buffa
authors.forename: Paul I
authors.initials: PI
authors.lastname: Richman
authors.forename: Søren M
authors.initials: SM
authors.lastname: Bentzen
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D049109:Cell Proliferation; D005260:Female; D006258:Head and Neck Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000532:radiotherapy*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000532:radiotherapy; D011878:Radiotherapy / Q000379:methods; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D019394:Ki-67 Antigen