• Posted June 14, 2023

Most Women With Early Breast Cancer Will Become Long-Term Survivors, New Study Shows

Most women diagnosed with early breast cancer will become long-term survivors, according to new research that finds a substantial reduction in the risk of death since the 1990s.

This news should reassure both patients and their doctors, researchers report June 13 in the BMJ.

“Our study is good news for the great majority of women diagnosed with early breast cancer today because their prognosis has improved so much," said the authors, who included Dr. Carolyn Taylor, a professor of oncology at the University of Oxford in England.

"Most of them can expect to become long-term cancer survivors,” they added in a journal news release.

While in the 1990s, the average risk of dying from breast cancer within five years of diagnosis was 14%, it's now 5%. More than 60% of women diagnosed during 2010 to 2015 had a five-year risk of 3% or less.

In addition to offering reassurance, the findings can also help identify those who still have substantial risk, according to the study.

Researchers used National Cancer Registration and Analysis Service data for more than 512,000 women who were diagnosed in England with early breast cancer between January 1993 and December 2015.

Early breast cancer is that which is confined to the breast or spreads only to the axillary lymph nodes. More than 2 million women are diagnosed with early breast cancer worldwide each year.

The team estimated annual breast cancer death rates and cumulative five-year risks, considering time since diagnosis, calendar period of diagnosis and women's characteristics such as age. They also looked at whether the cancer was detected by screening, involvement of lymph nodes, tumor size and tumor grade. They followed all the women until December 2020.

For women with a diagnosis made within each of the calendar periods 1993 to 1999, 2000 to 2004, 2005 to 2009, and 2010 to 2015, the annual death rate from breast cancer was highest within the five years after diagnosis. It then declined.

When the authors considered only the more than 156,000 women who were diagnosed most recently, between 2010 and 2015, the cumulative five-year breast cancer death risk varied substantially depending on a woman's characteristics.

It varied by patient age, whether the cancer was detected by screening, whether it had certain receptors, and according to cancer size, grade and the number of lymph nodes involved, the study noted.

While the risk was less than 3% for about 63% of women, it was more than 20% for nearly 5% of women.

The findings were observational and can't pinpoint causes of these reductions in death rates. Information on cancer recurrence was not available.

Another limitation is the study focused on women who were initially treated with surgery, not those treated to reduce the size of their cancer before surgery or those whose cancer had already spread.

Yet this analysis provides “patients with early breast cancer, and the clinicians who treat them, with estimates of their likely prognosis based on up-to-date data,” according to the study.

More information

The American Cancer Society has more on early screening for cancer.

SOURCE: BMJ, news release, June 13, 2023