Using data from the Auckland Breast Cancer Registry (ABCR) and the Waikato Breast Cancer Registry (WBCR), these researchers identified 2857 women newly diagnosed with grade 1 primary invasive breast cancer between 1 June 2000 and 31 May 2013. Almost one-fifth (19.0%) had axillary lymph node involvement, and recurrent disease (locoregional or distant) developed in 5.1%. Pacific and Māori women were more likely than NZ European women to have larger tumours and lymphovascular invasion (LVI). Predictors for axillary node involvement were tumour size >10 mm, LVI and non-screen detected cancers. Factors found to predict recurrent and/or metastatic disease were tumour size >10 mm, lobular carcinoma and breastconserving surgery without radiotherapy. Ethnicity did not independently predict axillary nodal involvement, recurrent and/or metastatic disease, or breast cancer-specific mortality in this patient population.
