Women who are diagnosed with early-stage invasive breast cancer and initially undergo surgery are 66 percent less likely to die from the disease today than they were 20 years ago, a new British study has found.
Worldwide, more than 2 million women are diagnosed with invasive breast cancer each year. For most people, this is their first cancer diagnosis. There are many types of breast cancer, and tumors can be aggressive or non-invasive. Noninvasive breast cancer is still contained in the milk ducts or lobules, while invasive breast cancer has spread from the milk ducts to surrounding tissues.
To inform treatment decisions and help women understand their disease, large population-based studies examining the impact of patient and cancer-related factors on breast cancer mortality are needed. Now, new research has done just that.
The study, carried out by researchers at the Oxford Center for Population Health at the University of Oxford, UK, was completed over a period of 10 years and is the first to show long-term outcomes for all women with first-time invasive breast cancer registered in England. People who were initially treated with surgery.
Data on 512,447 women diagnosed with early-stage breast cancer who underwent surgery between January 1993 and December 2015 were retrieved from the National Cancer Registry and Analysis Service. These women were followed until December 2020.
Participants were separated by year of diagnosis: 1993-99, 2000-04, 2005-09, and 2010-15. The researchers examined characteristics such as annual mortality, time since diagnosis and age at diagnosis, whether cancer was detected by breast screening, lymph node involvement, and tumor grade and size.
They found that for all women, the risk of death was highest up to five years after diagnosis and then declined. For women diagnosed with breast cancer in the 1990s, the risk of dying within five years of diagnosis averaged 14 percent. For those diagnosed between 2010-15, this dropped to an average of 5%. The researchers found that the improvement in prognosis applied to nearly all groups of women.
“Our study is good news for the vast majority of women diagnosed with early-stage breast cancer today, as their prognosis has improved dramatically,” said the study’s lead author, Carolyn Taylor. The risk of dying from breast cancer in the first five years after diagnosis now averages 5 percent.”
Although mortality rates fell in nearly all groups of women, the magnitude of the declines varied widely among women with different characteristics. The researchers say their results could help health professionals assess the prognosis of patients diagnosed with early-stage breast cancer.
“Our study could also be used to estimate risk for individual women in the clinic,” Taylor said. “This shows that prognosis after early breast cancer diagnosis varies widely. Patients and clinicians can use our results to estimate future prognosis. In the future, further research may be able to further reduce the risk of dying from breast cancer.”
The study did not address the reasons for the drop in mortality. However, since the 1990s, awareness of breast cancer has increased and the stigma surrounding the disease has decreased, leading more women to undergo mammograms, which allow for early detection and treatment.
The study was published in british medical journal.
source: Oxford university