Comprehensive trends in incidence, treatment, survival and mortality of first primary invasive breast cancer stratified by age, stage and receptor subtype in the Netherlands between 1989 and 2017

Abstract

Our study aimed to provide a comprehensive overview of trends in incidence, survival, mortality and treatment of first primary invasive breast cancer (BC), according to age, stage and receptor subtype in the Netherlands between 1989 and 2017. Data from all women diagnosed with first primary stage I to IV BC (N = 320 249) were obtained from the Netherlands Cancer Registry. BC mortality and general population data were retrieved from Statistics Netherlands. Age-standardised incidence and mortality rates were calculated with annual percentage change (APC) and average annual percentage change (AAPC) statistics. The relative survival (RS) was used as estimator for disease-specific survival. The BC incidence for all BC patients combined significantly increased until 2013 from 126 to 158 per 100 000 person-years, after which a declining trend was observed. Surgery became less extensive, but (neo-)adjuvant systemic treatments and their combinations were given more frequently. The RS improved for all age groups and for most stages and receptor subtypes, but remained stable for all subtypes since 2012 to 2013 and since 2000 to 2009 for Stage IV BC at 15 years of follow-up. Overall, the 5- and 10-year RS increased from 76.8% (95% confidence interval [CI]: 76.1, 77.4) and 55.9% (95% CI: 54.7, 57.1) in 1989 to 1999 to 91.0% (95% CI: 90.5, 91.5) and 82.9% (95% CI: 82.2, 83.5), respectively, in 2010 to 2016. BC mortality improved regardless of age and overall decreased from 57 to 35 per 100 000 person-years between 1989 and 2017. In conclusion, the BC incidence in the Netherlands has steadily increased since 1989, but the latest trends show promising declines. Survival improved markedly for most patients and the mortality decreased regardless of age.

Keywords: breast cancer; incidence; mortality; survival; treatment.

FIGURE 1

All ages combined and age‐specific first primary invasive breast cancer incidence (A) and mortality (B) trends (3‐year moving averages) in the Netherlands in the period 1989 to 2017. Rates were adjusted for age (European Standard Rates, ESR) by direct standardisation according to the 2013 European Standard Population 95+ and calculated per 100 000 person‐years (PY)

FIGURE 2

Incidence trends in the Netherlands stratified by receptor subtype between 2006 and 2017 in women diagnosed with first primary invasive breast cancer. Rates were adjusted for age (European Standard Rates, ESR) by direct standardisation according to the 2013 European Standard Population 95+ and calculated per 100 000 person‐years (PY). HR + = ER+ and/or PR+, HR− = ER− and PR−. Information on ER/PR and HER2‐status was routinely collected by the Dutch cancer registry since 2005 and 2006, respectively. Note the different scaling in A

FIGURE 3

Proportion of treatment received by patients with first primary invasive breast cancer in the Netherlands between 1989 and 2017. Targeted therapy (mainly trastuzumab) was routinely collected by the NCR since 2005. Cumulative proportion was calculated per treatment strategy and based on treatment received (yes/no). Proportions of mastectomy and breast‐conserving surgery were calculated based on the proportion of patients receiving surgery. Patients that received both surgical treatments were included in the mastectomy group

FIGURE 4

Age‐standardised relative survival (RS) outcomes with corresponding 95% confidence intervals of first primary invasive breast cancer in the Netherlands between 1989 and 2017. Relative survival was adjusted for age by direct standardisation according to the 2013 European Standard Population 95+

FIGURE 5

Age‐specific (A) and age‐standardised stage (B) and receptor subtype‐specific (C) relative survival outcomes with corresponding 95% confidence intervals of first primary invasive breast cancer patients in the Netherlands diagnosed between 1989 and 2016. Relative survival was adjusted for age by direct standardisation according to the 2013 European Standard Population 95+. HR + = ER+ and/or PR+, HR− = ER− and PR−. Information on ER/PR and HER2‐status was routinely collected by the Dutch cancer registry since 2005 and 2006, respectively. For Stage IV BC, the 20‐year relative survival in 2010 to 2016 could not be estimated due to low patient numbers