At diagnosis, pregnant women are more likely to have a larger tumor and a more aggressive type of breast cancer, which means that the prognosis is less good. This is apparent from the doctoral research of medical oncologist Britt Suelmann (UMC Utrecht).
Suelmann examined the characteristics of the breast tumors of 744 Dutch women who developed breast cancer during pregnancy or up to 6 months after childbirth. These data come from a Dutch pathology database that stores information from women who received this diagnosis between 1988 and 2019.
The research shows that breast cancer during pregnancy is a different type of cancer than breast cancer in non-pregnant women. Two types of breast cancer are more common in pregnant women: HER2-positive breast cancer and triple-negative breast cancer. Hormone-sensitive breast cancer – the most common form of breast cancer – is actually less common in pregnant women
Furthermore, it appears that breast tumors detected in the second and third trimesters have different characteristics and are more aggressive than tumors detected in the first trimester. Also tumors of women who are breastfeeding are more aggressive. The survival of these groups is also worse. Suelmann obtained his doctorate from Utrecht University on March 29.
Source:
UMC Utrecht