Controlled ovarian hyperstimulation in breast cancer patients: Does oestrogen receptor status make a difference?

Abstract

Background: The presence of different breast cancer receptor status may impact ovarian stimulation outcomes.

Aim: To study the association between oestrogen receptor (ER) status in breast cancer patients and fertility preservation outcomes in a major tertiary referral centre.

Materials and methods: Women who underwent fertility preservation following the diagnosis of breast cancer from 2008 to 2018 were included in the study. Patient age, ovarian stimulation parameters and laboratory outcomes were recorded and compared between the ER positive and negative groups. The primary outcome was total number of oocytes frozen. Secondary outcomes included total number of oocytes collected, mature oocytes, and embryos frozen.

Results: The women included in the study (n = 214) were analysed in the following groups based on their fertility preservation method: oocyte freezing (n = 131), embryo freezing (n = 70), and both embryo and oocyte freezing (n = 13). There was an increase in the mean (but not mature) number of oocytes frozen (12.4 and 9.2, P-value = 0.03) favouring the ER positive group, even though the women in this group were older (35.0 and 33.4, P-value of 0.03). There is no difference in the starting follicle-stimulating hormone dose, duration of stimulation, mature oocytes collected, and embryos frozen in both groups.

Conclusion: Patients with ER positive breast cancer may have more positive ovarian stimulation outcomes.

Keywords: breast cancer; controlled ovarian stimulation; fertility preservation; oestrogen receptor.