P –465 Effect of letrozole over Ki–67 expression in breast cancer during controlled ovarian stimulation (COS) for fertility preservation (FP): case report

AbstractStudy questionDoes concomitant letrozole administration during COS alter Ki –67 expression in women undergoing FP procedures before breast cancer surgery?Summary answerConcomitant letrozole administration during COS, even for a short period, can reduce Ki –67 expression in breast cancer.What is known alreadyThe biggest concern with COS in breast cancer patients is the increase in serum estradiol levels, caused by the development of multiple follicles simultaneously. This has always been a major hindrance to the use of traditional ovarian stimulation regimens in these patients, due to the large amount of evidence on the pathogenetic role of estrogen in breast cancer propagation. To limit the rise of estradiol during COS, most centers have adopted concomitant letrozole administration. Recently, some studies have reported changes in tumor pathology after letrozole administration, such as a significant fall in Ki –67 expression.Study design, size, durationCase report including 2 patients undergoing COS with concomitant letrozole administration for 12 days before breast cancer surgery.Participants/materials, setting, methodsThe first patient was a 28-year-old Caucasian woman with a breast biopsy showing an infiltrating ductal carcinoma in the upper external quadrant of the right breast. The second patient was a 33-year-old Caucasian woman with a diagnosis of infiltrating ductal carcinoma of the upper external quadrant of the left breast. Both patients underwent COS w...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research