By Lisa Rapaport
(Reuters Health) – New study suggests screening mammograms do not benefit women aged 75 and older with chronic health conditions, such as heart disease or diabetes, that could end their days before cancer .
The researchers examined data from 222,088 women who underwent at least one screening mammogram between 1999 and 2010, aged 66 to 94 years. The researchers followed most women for nine years or more.
During the study, 7,583 women, or about 3%, were diagnosed with invasive breast cancer and 1,742 women, less than 1%, were diagnosed with a pre-invasive cancer called ductal carcinoma. situ (DCIS). While 471 women died of breast cancer during the study, 42,229 died from other causes.
This means that women are 90 times more likely to die from causes other than breast cancer, researchers report in the Journal of the National Cancer Institute.
"Having more chronic diseases increases the risk of dying from causes other than breast cancer, while having no impact on the risk of breast cancer or breast cancer deaths," said lead author Dejana Braithwaite. of the study and researcher at the Lombardi Comprehensive Cancer Center. at Georgetown University in Washington, DC
"This is a big problem because even though younger women may have a more legitimate reason for having a breast screening mammogram because they are at a relatively low risk of dying from other causes, older women, especially those who have it, are not. or several chronic diseases, "said Braithwaite by email.
Women aged 75 to 84 were 123 times more likely to die from causes other than breast cancer; this estimate was even higher for women aged 85 and over.
The risk of death from breast cancer over 10 years was low and did not vary with age; it remained about the same from 66 to 94 years of age, accounting for only 0.2% to 0.3% of all study deaths.
In contrast, the risk of dying from other causes increased with age and increased with each additional chronic medical problem that a woman had.
Mammography screening aims to detect tumors before they can be felt during a physical breast exam, in order to screen for cancer earlier when it is easier to treat. Ideally, this should mean that fewer women are diagnosed when the tumors are bigger, faster growing and more difficult to attack.
However, some research suggests that screening too soon or too often can also detect more small, slow-growing tumors that are unlikely to become fatal, without compromising the diagnosis of advanced cancer cases. Excessive screening may include unnecessary invasive follow-up tests and cancer treatments for tumors that would never have made women ill or leading to death.
The Preventive Services Working Group in the United States notes that there is not enough evidence to recommend or not to screen women aged 75 or older. In Europe, many breast cancer programs stop screening women aged 69 to 74 years.
In the United States, despite these recommendations, many women between the ages of 80 and 90 are still undergoing screening mammography, the study team notes.
One of the limitations of the analysis was that it included only women who continued to have a screening mammogram as they got older, and that the results obtained for all women in the population, including those who have ceased to have mammograms, may be different, the researchers noted.
"Our study included a large number of older women unlikely to benefit from screening mammography," Braithwaite said. "Continuous mammograms should not be beneficial to women aged 75 and over, but these findings underscore the need for more individualized screening strategies, rather than making radical recommendations."
SOURCE: https://bit.ly/2kcRguy Journal of the National Cancer Institute, posted on September 6, 2019.