Summary
Breast cancer mortality in 500,000 women with early invasive breast cancer in England, 1993-2015: population-based observational cohort study
Goals
To describe long-term breast cancer mortality among women with a past diagnosis of breast cancer and to estimate the absolute risks of breast cancer mortality for groups of patients with a recent diagnosis.
Design
Population-based observational cohort study.
Around
Data routinely collected from the National Cancer Registry and Analysis Service.
Participants
All 512,447 women registered with early invasive breast cancer (affecting only the breast and possibly axillary nodes) in England between January 1993 and December 2015, with follow-up until December 2020.
Main outcome measures
Annual breast cancer mortality rates and cumulative risks by time since diagnosis, calendar period of diagnosis, and nine patient and tumor characteristics.
Results
For women with a diagnosis made within each of the calendar periods 1993-99, 2000-04, 2005-09, and 2010-15, the crude annual breast cancer mortality rate was highest during the five years after diagnosis. diagnosis and then decreased. At any given time since diagnosis, crude annual breast cancer mortality rates and risks decreased with increasing calendar period.
The five-year crude risk of breast cancer mortality was 14.4% (95% confidence interval: 14.2% to 14.6%) for women diagnosed between 1993 and 1999 and 4.4% (95% confidence interval: 14.2% to 14.6%). 9% (4.8% to 5.0%) for women with a diagnosis made during 2010-15.
Adjusted annual breast cancer mortality rates also decreased with increasing calendar period in almost all patient groups, by a factor of about three in estrogen receptor-positive disease and about two in estrogen receptor-positive disease. negative.
Conclusions These five-year breast cancer mortality risks for newly diagnosed patients can be used to estimate breast cancer mortality risks for patients today. The prognosis for women with early invasive breast cancer has improved substantially since the 1990s. Most can expect to become long-term cancer survivors, although for a few the risk remains appreciable. |
Comments
The number of people dying after a breast cancer diagnosis has fallen by two-thirds since the 1990s, a study of more than half a million women in England showed.
The research has taken ten years to complete, says Carolyn Taylor, lead author and oncologist at the University of Oxford, UK. The analysis includes all 512,447 women in England who were diagnosed with early invasive breast cancer between January 1993 and December 2015; The researchers tracked the women through December 2020 using data from the National Cancer Registry and Analysis Service.
Women who were diagnosed between 1993 and 1999 had a 14.4% risk of dying within 5 years. This dropped to 4.9% for women diagnosed in 2010-15 (see ’Improved odds’). The results were published on June 13 in The BMJ.
“We knew mortality had gone down over the last 20 years, but we didn’t know by how much,” Taylor says. “That’s a two-thirds reduction.”
Long term results
The study showed that the risk of death decreased in almost all age groups, both for women who were diagnosed with cancer through screening and for those who had not been screened.
However, the reasons for the drop are unclear. Since the 1990s, awareness of breast cancer has increased and in England more women are being offered routine screening. Randomized trials have explored how specific treatments affect survival after diagnosis. “What we can’t do is say how much of the improvement is due to treatment or screening or breast cancer awareness,” Taylor says.
The decline in the death rate was not a surprise, says Naser Turabi, director of evidence and implementation at Cancer Research UK (CRUK) in London. CRUK funded the research, but Turabi was not involved in the study. “Research is incredibly important in determining the success of treatments,” he says, and this study will help patients make more informed decisions about their treatment.
Patient participation was important to the study, Taylor says. The scientists appointed two patient representatives to guide their research. “They helped us with the issues to discuss. They reviewed the analyzes and provided comments and suggestions throughout the study. And they helped us interpret the results in a way that patients can understand.”
Large-scale studies like this one that track outcomes over many years are important for setting research and funding priorities, Turabi says. “Fundamentally, if we cannot track the success of the interventions we implement, the case for those interventions is weakened.”
Reference : Huge leap in breast-cancer survival rate. Katharine Sanderson. Nature doi: https://doi.org/10.1038/d41586-023-02075-w
