Breast cancer diagnosis following ovarian stimulation: are the tumours different?

Demographic data and tumour characteristics of 18 patients (study group) diagnosed with breast cancer within 24 months of undergoing ovarian stimulation with either gonadotrophins or clomiphene citrate were evaluated and compared with similar 102 age-matched women diagnosed with breast cancer without prior infertility treatment (control group). Eight out of 17 (47.1%) patients in the study group and 35/95 (36.8%) patients in the control group had positive family history for breast cancer. Median tumour size was similar in the study and control groups (both 1.3 cm). Both groups were comparable regarding tumour histological types and oestrogen receptor, progesterone receptor and Her2/Neu expression status. Albeit not significant, stage 0 tumours were more prevalent in the study group compared with the control group (22.2% versus 10.5%), and there were no stage III tumours in the study group as opposed to 7/95 in the control group. In conclusion, breast cancer diagnosed within the first 2 years following infertility treatment is similar in tumour characteristics compared with those occurring in patients without prior infertility treatment.