Observational interrogation of procedural databases demonstrated possible increase in time to tumour recurrence and 3- and 5-year overall survival in patients with ovarian cancer,75,76 reduced risk of biochemical (i.e. prostate-specific antigen) recurrence and clinical cancer progression after radical prostatectomy,77,78 decreased all-cause mortality in patients with rectal cancer,79 and improved recurrence and metastasis-free survival in patients after surgery for breast cancer.80 This evidence concerns the gene KLK3 and rectal cancer.