Trends in the prognosis of patients with primary metastatic breast cancer diagnosed between 1975 and 2002.

We performed a population-based study, including 1089 patients with primary metastatic breast cancer, diagnosed in South-East Netherlands between 1975 and 2002, and tried to give an answer to the question if prognosis of this patient group has improved or not. Follow-up was completed until 1 January 2005. The median survival times for patients with primary metastatic disease were 18, 17 and 20.5 months for patients diagnosed in the periods 1975-1984, 1985-1994 and 1995-2002, respectively. A multivariate analysis, including age, tumour size and information on the localization of metastatic disease and the number of metastatic sites, showed that patients diagnosed in the period 1995-2002 had a 18% lower death risk (95% confidence interval 5-30) compared to those diagnosed in the period 1985-1994. These data show that the prognosis of patients with primary metastatic breast cancer remained unchanged between 1975 and 1994 and that some progress has been made after 1994.