Having a child is a decision with serious consequences. This is even more true for women who have had breast cancer, and must stop their treatment to get pregnant. A new study is rather reassuring. Pregnancy does not increase the risk of recurrence.
- Breast cancer with positive hormone receptors is a hormone sensitive cancer. This means that the growth of the malignant tumor is stimulated by hormones (estrogen or progesterone).
- The authors specify that it was strongly recommended that the patients in the study resume hormone therapy after an attempted or successful pregnancy. To date, 76.3% have returned to care.
Fertility is an important issue for women affected by breast cancer. “40-60% of patients who are diagnosed with breast cancer at age 40 or younger worry about their future fertility, especially if the disease occurs before they can decide whether or not to become a mother”explained co-author Dr. Ann Partridge, vice president of the Dana-Farber Cancer Institute and professor of medicine at Harvard.
However, his study, presented at San Antonio Breast Cancer Symposium held in late 2022, is rather reassuring for patients treated with hormone therapy. Their baby project does not increase the risk of recurrence.
Temporarily stopping treatment does not increase the risk of recurrence
The scientist wanted to determine the impact of suspending hormone therapy to continue a pregnancy. She and her team brought together 518 women under the age of 42 diagnosed with breast cancer with positive hormone receptors. Having followed between 18 and 30 months of hormone therapy, they wanted to stop the care to get pregnant. The volunteers came from 20 countries (23% from North America, 61% from Europe and 16% from Asia/Pacific and Middle Eastern countries).
During the follow-up organized from December 2014 to December 2019, 368 women (74%) became pregnant at least once and 317 (63.8%) gave birth. During these 5 years of research, 365 babies were born. “These conception and delivery rates were equal to or higher than those of the general public”said co-author Dr. Olivia Pagani.
At a median follow-up of 41 months, 44 participants experienced a recurrence of breast cancer. The recurrence rate over three years was thus 8.9%, similar to the rate of 9.2% in a control cohort.
These results allow the authors to conclude that patients with breast cancer who interrupted their treatment to have a child experienced short-term breast cancer recurrence rates similar to those who did not stop treatment. hormone therapy to get pregnant.
Pregnancy after breast cancer, how to decide?
Researchers Ann Partridge and Olivia Pagani believe that their work shows encouraging results for young women diagnosed with breast cancer. However, they note that the decision to stop treatment to have a child should be taken after consultation with health professionals.
“The POSITIVE trial provides important data to support young women with hormone receptor positive breast cancer who want pregnancy and who are interrupting hormone therapy to continue one”acknowledged Dr. Partridge.
“Pregnancy after breast cancer is a very personal decision for which, ideally, a woman should consider not only her desire to conceive, but also her baseline fertility, past and current treatment, and any fertility preservation strategies she may have pursued, as well as the underlying risk of cancer recurrence she faces”added his colleague.
The two scientists continue to follow the study participants to assess the risk of recurrence over time. Indeed, they recognize that the short follow-up is a limitation of their study, because breast cancer with positive hormone receptors can reappear several years after an initial diagnosis.