Women with breast cancer can safely discontinue their hormone therapy if they want to get pregnant, according to a new study in which UZ Leuven participated.
Discontinuing the medication does not lead to an increased risk of cancer recurrence in the short term, compared to women who simply continue their treatment, the study found.
Five percent of women with breast cancer are under the age of 40. After their treatment for the disease, women with hormone-sensitive tumours have to undergo hormone therapy for another five to ten years, during which time they cannot conceive, the study recalled.
As a result, many young women with breast cancer have had to postpone or even give up their desire to become pregnant.
However, the study shows that women can safely stop their hormone therapy after two years to conceive a child.
The study, conducted from December 2014 to December 2019, followed 518 women aged 42 or younger who wanted to become pregnant. The patients agreed to suspend their hormone therapy for about two years in an attempt to fulfill their desire to become pregnant. Before discontinuing their treatment, they had been on hormone therapy for 18 to 30 months.
The study included patients from 116 hospitals, 20 different countries and four continents.
The results showed that the risk of cancer recurrence was no higher in patients who paused treatment than in those who continued. The percentage of women whose breast cancer returned after discontinuation was comparable to those who did not discontinue treatment. As a result, almost all the women were able to fulfil their maternity wish and give birth to a healthy baby.
As the patients were only followed for three years, the researchers could only comment on the short-term effects in terms of recurrence. However, aggressive cancers often recur within three years, which makes the figures reassuring from a scientific point of view. The women who took part in this study will continue to be monitored.
"The decision to stop the therapy must of course be taken in close consultation with the treating doctors, because the situation is different for each woman," emphasised Professor Frédéric Amant, a gynaecologist at UZ Leuven who took part in the study. "It is also important for doctors to ensure that women complete their hormone therapy after the planned break."
