Why does breast cancer re-occur? A study tries to better understand
TOKYO – For women who have overcome breast cancer, there is a shadow of recurrence, sometimes up to 20 years after the first diagnosis. A study published on Wednesday seeks to identify those who are most at risk, to better treat them.
Some of the known risk factors for recurrence are the age of the patient, the size and nature of the tumor, or the presence of cancer cells in the lymph nodes.
But the rate and reasons for recidivism remain “poorly understood,” says a study published in the journal Nature.
To better understand them, the researchers analyzed data from 3,000 British and Canadian patients diagnosed with breast cancer between 1977 and 2005.
All of this data was used to develop a computer model that identified four subgroups with “a particularly high risk of late relapse” of cancer, according to the study’s lead author, Christina Curtis, of Stanford University. (United States).
According to the study, about one-quarter of women affected by the most common form of breast cancer had a 42-55% chance of seeing their cancer recur within 20 years.
“So far, it’s unclear what subgroup of women might benefit from screening or treatment,” says Christina Curtis.
The study also opens up new avenues for additional breast cancer treatments by identifying genetic alterations in each of the four risk subgroups. These alterations are related to the process of tumor formation.
“Many of these alterations can potentially be targeted by therapies, which opens the door to possible new treatments, although it still needs to be verified in clinical trials,” Curtis told AFP. .
The study also identified patients for whom recurrence after five years was unlikely.
“This could help improve patient follow-up and classification, for example by determining which ones might benefit from longer or different treatments,” says Christina Curtis.