Patient Factors May Be Associated With Fertility After Breast Cancer Treatment

Patient Factors May Be Associated With Fertility After Breast Cancer Treatment

Nearly three-fourths of survivors of stage I-III breast cancer who tried to conceive after treatment were successful in becoming pregnant, according to findings presented ahead of the 2024 ASCO Annual Meeting.

“The current research that informs our understanding of the impact of breast cancer treatment on pregnancy and life birth rates is fairly limited,” study author, Kimia Sorouri, MD, PhD, said in a presentation of the data. “This is the first prospective study with greater than 10 years of follow-up to report fertility outcomes in young breast cancer survivors account for attempting pregnancy.”

Sorouri is a member of the Breast Oncology Program at the Dana-Farber Cancer Institute in Boston.

“Many young women who are diagnosed with breast cancer are interested in future fertility,” Sorouri said. “However, many cancer treatments can impair an individual’s fertility and their ability to carry a pregnancy.”

Researchers analyzed data from the prospective Young Women’s Breast Cancer Study. It included 1213 patients under the age of 40 who received a diagnosis of stage 0 to stage 3 breast cancer between the years 2006 and 2016. Of note, patients with metastatic disease or who had their uterus or ovaries removed were not included in the study.

Among these participants, 197 reported that they attempted pregnancy over a median follow-up of 11 years. In this group, 73% became pregnant at least once, with 90% of these patients reporting a live birth. The median time to diagnosis to the first pregnancy was four years, according to the data and the median age diagnosis 32 years (range, 17-30).

About half of patients reported being financially comfortable, with 72% reported never having a live birth before diagnosis. A total of 28% of patients underwent fertility preservation (via cryopreservation of embryo and/or eggs). Fifteen percent of patients had a known history of infertility before receiving the breast cancer diagnosis.

Regarding disease and treatment history of those who became pregnant, the majority (76%) had ER- and/or PR-positive disease, followed by HER2-positive disease (25%) and triple-negative breast cancer (17%).

Sixty-eight percent (n=133) of patients received chemotherapy; 57% (n=113) received endocrine therapy; 58% (n=114) radiation; 38% (n=74) lumpectomy; 22% (n=43) unilateral mastectomy; and 41% (n=80) bilateral mastectomy.

Data showed that factors associated with a higher chance of becoming pregnant included: being younger at the time of diagnosis; being financially comfortable, defined as still having enough money left over to “buy special things after paying bills”; having undergone fertility preservation.

“While having undergone fertility preservation at diagnosis prior to receiving their cancer treatment was predictive of a live birth, the other patient cancer and treatment factors collected are not associated with either outcome,” Sorouri said.

The researchers also uncovered factors that did not seem to have an impact on the chance of pregnancy or birth. They were:

• A history of infertility
• Having previous births
• Characteristics of breast cancer
• Type of treatment received
• BRCA germline mutation status
• Race or ethnicity

“This suggests that in this modern cohort with a heightened awareness of fertility, access to fertility preservation can help to mitigate a portion of the damage from chemotherapy and other agents,” Sorouri said. “Importantly, this highlights the need for increased accessibility of fertility preservation services for women newly diagnosed with breast cancer who are interested in your pregnancy.”

Reference

Sorouri K, Zheng Y, Niman SM, et al. Fertility among young breast cancer survivors attempting pregnancy: A prospective, multicentre cohort study. J Clin Oncol. 2024;42(suppl 16):1518.