Temporary Interruption of Endocrine Therapy for Breast Cancer Safe

THURSDAY, May 4, 2023 (HealthDay News) -- Among select women with previous hormone receptor-positive early breast cancer, there is no increase in the short-term risk for breast cancer events with temporary interruption of endocrine therapy to attempt pregnancy, according to a study published in the May 4 issue of the New England Journal of Medicine.

Ann H. Partridge, M.D., M.P.H., from the Dana-Farber Cancer Institute in Boston, and colleagues examined the temporary interruption of adjuvant endocrine therapy to attempt pregnancy in young women with previous breast cancer (aged 42 years or younger). A total of 516 participants had had stage I, II, or III disease (93.4 percent stage I or II), received adjuvant endocrine therapy for 18 to 30 months, and desired pregnancy. Overall, 497 women were followed for pregnancy status.

The researchers found that 74.0 percent of the women had at least one pregnancy and 63.8 percent had at least one live birth. Overall, 365 babies were born. Forty-four patients had a breast cancer event at 1,638 patient-years of follow-up (median follow-up, 41 months); this did not exceed the prespecified safety threshold of 46 breast cancer events. The three-year incidence of breast cancer events was 8.9 and 9.2 percent in the treatment-interruption and control cohorts, respectively.

"The POSITIVE trial provides prospective data showing that the temporary interruption of endocrine therapy to attempt pregnancy after hormone receptor-positive early breast cancer does not appear to increase the risk of recurrence or of contralateral breast cancer in the subsequent three years," write the authors of an accompanying editorial. "Physicians should now incorporate these positive data into their shared decision-making process with patients."

Abstract/Full Text (subscription or payment may be required)

Editorial (subscription or payment may be required)