A Phase 4 interventional study of Letrozole and standard-stimulated cohort in Breast Neoplasm Malignant Female, sponsored by Erasme University Hospital. Terminated at 6 sites in 3 countries. Open to female participants aged 18 Years to 40 Years. Per ClinicalTrials.gov, last updated 2025-01-31.
Sponsored by Erasme University Hospital · Phase 4, Interventional, and Prevention
This is a multicenter hospital-based prospective cohort study conducted in institutions with known expertise in performing oocytes/embryo freezing for fertility preservation. The study aims at refining the understanding of the efficacy and safety of controlled ovarian stimulation with or without letrozole in young women with newly diagnosed breast cancer who are candidates to receive (neo)adjuvant chemotherapy.
Patients enrolled in this study undergo standard or "random start" ovarian stimulation with Gonadotropins using antagonist protocol before the beginning of chemotherapy. Ovulation is triggered in all patients with a Gonadotropin Releasing Hormone-GnRH agonist.
After retrieval, oocytes are denuded and matured oocytes are subjected to fertilization before embryo freezing or direct vitrification.
Primary objective is to evaluate the efficacy of performing a controlled ovarian stimulation with or without letrozole in young women with newly diagnosed breast cancer who are candidates to receive (neo)adjuvant chemotherapy in terms of mature oocytes collected.
Erasme University Hospital is the lead sponsor of 180 studies on the registry; 34 are open to participants now.
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Exclusion Criteria:
this cohort includes all newly diagnosed breast cancer patients who are candidates to receive (neo)adjuvant chemotherapy and wish to preserve their fertility by undergoing oocyte/embryo cryopreservation at the French participating centres.
Other: standard-stimulated cohort
this cohort includes all newly diagnosed breast cancer patients who are candidates to receive (neo)adjuvant chemotherapy and wish to preserve their fertility by undergoing oocyte/embryo cryopreservation at the Belgian participating centres.
Drug: Letrozole
this cohort includes all newly diagnosed breast cancer patients who are candidates to receive (neo)adjuvant chemotherapy and who have access to the Fertility Clinics in all the participating centres but are not willing to preserve their fertility by undergoing oocyte/embryo cryopreservation.
Patients start ovarian stimulation protocol according to their menstrual cycle phase at enrollment (standard or "random start"). Ovarian stimulation includes gonadotropins administration in a GnRH antagonist protocol. "Standard Protocol": letrozole is orally administered (5mg/d) from cycle day 2-3 throughout the ovarian stimulation with gonadotropins protocol until ovulation triggering. "Random start" protocol: letrozole is administered throughout the stimulation together with gonadotropins. GnRH antagonist is administered at cycle day 7 or as soon as at least one follicle reaches 12-14 mm. Oocytes are collected 36h after ovulation triggering with GnRH agonist.
Also known as: Controlled Ovarian Stimulation (COS)
Patients start ovarian stimulation protocol according to their menstrual cycle phase at enrollment (standard or "random start"). Ovarian stimulation includes gonadotropins administration in a GnRH antagonist protocol. "Standard Protocol": Gonadotrophins started from cycle day 2-3 throughout the ovarian stimulation until ovulation triggering. "Random start" protocol: Gonadotrophins started at any time of the cycle and throughout the stimulation. GnRH antagonist is administered at cycle day 7 or as soon as at least one follicle reaches 12-14 mm. Oocytes are collected 36h after ovulation triggering with GnRH agonist.
Also known as: COS
Efficacy of the ovarian stimulation and oocyte collection procedure: Number of mature oocytes collected
Number of mature oocytes collected
Time frame: an average of 2 weeks after inclusion
Number of patient with adverse events due to COS: OHSS
Adverse events reporting during COS (Ovarian Hyperstimulation syndrome-OHSS)
Time frame: Through treatment procedure, an average of 2 weeks after inclusion
Characteristics of Ovarian stimulation: total gonadotropin doses
Total gonadotropin doses (International Unit- IU)
Time frame: An average of 2 weeks after inclusion
Characteristics of Ovarian stimulation: duration of the COS
duration of the COS (days)
Time frame: An average of 2 weeks after inclusion
Characteristics of Ovarian stimulation: type of stimulation
type of stimulation (standard or random-start).
Time frame: An average of 2 weeks after inclusion
Efficacy of the ovarian stimulation and oocyte collection: Maturation rate
Maturation rate (number of total oocyte collected/number of mature oocytes)
Time frame: An average of 2 weeks after inclusion
Outcomes of assisted reproductive technology procedures
Number of pregnancies and outcomes (premature delivery, miscarriage, abortion, delivery healthy babies, congenital malformation).
Time frame: Through study completion, 5 years
Anticancer therapies effect on ovarian function: progesterone
Hormonal measurements Progesterone ng/ml
Time frame: Inclusion, an average of 2 weeks, 6 months, 18 months, 30 months, 60 months
Anticancer therapies effect on ovarian function: AMH
Anti-Mullerian Hormone (AMH) measurements AMH ng/ml
Time frame: Inclusion, an average of 2 weeks, 6 months, 18 months, 30 months, 60 months
Anticancer therapies effect on ovarian function: FSH
Follicle-Stimulating Hormone (FSH) measurements FSH IU/L
Time frame: Inclusion, an average of 2 weeks, 6 months, 18 months, 30 months, 60 months
Anticancer therapies effect on ovarian function: E2
Hormonal measurements E2 pg/ml
Time frame: Inclusion, an average of 2 weeks, 6 months, 18 months, 30 months, 60 months
Anticancer therapies effect on ovarian function
Amenorrhea rate (6months without spontaneous menstruation)
Time frame: An average 18 months, 30 months, 60 months after inclusion
Oncological outcomes 1
Invasive disease-free survival (iDFS)
Time frame: 5 years
Oncological outcomes 2
breast cancer-free interval (BCFI)
Time frame: 5 years
Oncological outcomes 3
overall survival (OS)
Time frame: 5 years
Circulating breast cancer cells level before stimulation
circulating tumor DNA (ctDNA)
Time frame: Inclusion
Circulating breast cancer cells level after stimulation
circulating tumor DNA (ctDNA)
Time frame: average of 2weeks after inclusion
Number of patient with adverse events due to egg collection
bleeding
Time frame: An average of 2 weeks after inclusion
Number of patient with adverse events due to egg collection
pelvic infection
Time frame: An average of 2 weeks after inclusion
Efficacy of the in vitro fertilization procedure: Fertilization rate
Fertilization rate (number of oocyte fertilized/number of embryo obtained)
Time frame: Through study completion, 5 years
Documents are hosted by the registry — open the source record to download them.
Plan to share: No
Ran from Feb 2019 to primary completion in Jan 2025, 70 months.
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This study is terminated, as verified in Dec 2024. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Letrozole