We then performed multivariate reverse stepwise Cox regression modelling (with a threshold for removal from the model of p>0.05) for each of g-H2AX, ATM and Ku70, including as co-variates age, gender, Dukes stage, tumour location, trial arm (rofecoxib vs. placebo), chemotherapy status, radiotherapy status, CIN, KRAS and BRAF mutation status and MSI (Table 2). The gene discussed is XRCC6; the disease is neoplasm.