Cancer Res Treat.  2020 Apr;52(2):426-437. 10.4143/crt.2018.382.

Outcomes of Pregnancy after Breast Cancer in Korean Women:A Large Cohort Study

• Lee MH
• Kim YA
• Hong JH
• Jung SY
• Lee S
• Kong SY
• Park B
• Lee ES

• KMID: 2500328
• DOI: http://doi.org/10.4143/crt.2018.382

Abstract

Purpose
The purpose of this study was to determine the rate and outcomes of pregnancies subsequent to breast cancer in Korea, and the effect of such pregnancies on the prognosis of women who survived breast cancer and subsequently conceived.
Materials and Methods
We followed a total of 31,761 Korean women 45 years of age or younger who were treated for primary breast cancer from 2002 to 2010. We also included follow-up surveys that were conducted through December 2011. We identified recurrence and mortality from breast cancer using data linked to the Korea National Health Insurance database. We used propensity score matching of the study cohort to analyze the risks of recurrence and mortality from breast cancer depending on pregnancy.
Results
Within our sample, 992 women (3.1%) became pregnant after receiving treatment for breast cancer. Of those, 622 (67.5%) successfully delivered; the remaining 370 (32.5%) failed to deliver. After propensity score matching, we found that the women who became pregnant after breast cancer did not have a different risk of recurrence (hazard ratio [HR], 0.503; 95% confidence interval [CI], 0.434 to 0.584) and death (HR, 0.520; 95% CI, 0.397 to 0.681), compared with those who did not conceive after breast cancer treatment.
Conclusion
Our study is the first to report outcomes for Korean women who survived breast cancer and subsequently conceived. Women who survived breast cancer and subsequently became pregnant did not show a poorer survival outcome, compared with those who did not become pregnant.

Keyword

Breast neoplasms; Pregnancy; Cancer survivors

Figure

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  Fig. 1. Diagram of patient recruitment for the study.

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  Fig. 2. Recurrence-free survival (RFS) and overall survival (OS) according to history of pregnancy and delivery subsequent to breast cancer treatment among all patients. (A) RFS, pregnancy vs. non-pregnancy. (B) OS, pregnancy vs. non-pregnancy. (C) RFS, according to history of pregnancy and delivery. (D) OS, according to history of pregnancy and delivery.

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  Fig. 3. Recurrence-free survival (RFS) and overall survival (OS), according to history of pregnancy and delivery subsequent to breast cancer treatment, after propensity score matching. (A) RFS, non-pregnancy vs. pregnancy. (B) OS, pregnancy vs. non-pregnancy. (C) RFS, non-pregnancy vs. failed to deliver. (D) OS, non-pregnancy vs. failed to deliver. (E) RFS, non-pregnancy vs. successful delivery. (F) OS, non-pregnancy vs. successful delivery. (G) RFS, failed to deliver vs. successful delivery. (H) OS, failed to deliver vs. successful delivery.

Reference

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