Screening of asymptomatic women for breast cancer is associated with reduced breast cancer mortality and is practised in almost all developed countries. Breast cancer screening was introduced to the West of Ireland in 2008 with the arrival of BreastCheck West. Since then, many thousands of women aged 50-65 have been screened and hundreds have had cancers diagnosed and treated successfully by this service. Breast cancer screening remains controversial as critics argue that the cancers diagnosed by screening are slow growing, indolent tumours unlikely ever to harm the patient (described by some as “tortoises”), compared with the more aggressive fast-moving cancers (“hares”) or the almost-impossible-to-control rapidly-metastasising (“birds”).
The BreastCheck screening programme has been collecting data since its inception, but has never analysed this in any formal retrospective review.
We plan to review all breast cancers diagnosed by BreastCheck since 2008 until 2001 with and present data relating to classic features of aggressiveness: size, histological type, grade, hormone receptor profile, Her2 status, Nottingham Prognostic Index, and Oncotype genetic score, in order to see if the cancers being diagnosed in the West of Ireland are indeed indolent tumours with limited pathogenic potential, or whether, as we suspect, there is a sizeable proportion of more aggressive cancers which were destined to harm the patient if left untreated. We will also analyse survival data of screened patients. These data will be compared to features and survival of breast cancers diagnosed by other screening services (if available) and data from breast cancers of symptomatic patients.
