A review of the incidence and coincidence of uterine and mammary tumours in Wistar and Sprague Dawley rats based on the RITA database and the role of prolactin Evaluation of carcinogenicity results needs an awareness of tumour interdependency in pathogenesis

Wistar rats are frequently selected for use in carcinogenicity studies due to their advantageous survival rate, which is more favourable than other strains such as the Sprague Dawley (SD) strain. Uterine and mammary tumurs are relatively common spontaneous neoplasms of both strains. We examined the incidence and co-incidence of uterine tumours and mammary tumours in control animals of both strains within the RITA database. There was a strong inverse relationship between these tumour types in Wistar rats (p10%