Letrozole-associated controlled ovarian hyperstimulation in breast cancer patients versus conventional controlled ovarian hyperstimulation in infertile patients: assessment of oocyte quality related biomarkers

Cancer Therapy, Gonadal Function, and Fertility Preservation: Narrative Review

PURPOSE

Fertility preservation was designed to help young patients overcome complications of cancer treatments, but its effectiveness is unknown. We sought to investigate how often patients with cancer are offered fertility preservation and if patients offered fertility preservation are more likely to have offspring.

METHODS

We searched Embase (through 2022) and PubMed (through 2022). Our broad computerized search strategy was built upon using the keywords "chemotherapy," "radiation," and "fertility." The search took place on December 1, 2022. We included randomized and observational studies and excluded reviews and case reports/series.

RESULTS

Eighty-five articles that answered at least one of the research questions were included. Studies assessing fertoprotective therapies often rely on surrogate markers for fertility. Multiple factors affect these markers of fertility. The median premature ovarian failure rate among the intervention group was 18% (IQR, 12%-20%), and among the control group, it was 25% (IQR, 19%-33%). Five of 11 studies reported a significant benefit from fertoprotective therapy. Pregnancies occurred in a median of 21% (IQR, 6%-52%) of patients in the intervention group and 11% (IQR, 7-44) of patients in the control group, with three of seven studies reporting a higher percentage of pregnancies among the intervention group.

CONCLUSION

We reviewed the literature on several questions surrounding fertility preservation and found that there is limited and low-quality research on these therapies in cancer. Hence, there is a strong need for studies, especially randomized studies, that follow patients with cancer who undergo fertility preservation and assess outcomes in which patients are most interested.

In vitro maturation in synthetic oviductal fluid increases gene expression associated with quality and lipid metabolism in bovine oocytes

Traditionally, in vitro oocyte and embryo culture progresses through a series of varying culture medium. To investigate simplifying the in vitro production of bovine cumulus-oocyte complexes (COCs), this study used synthetic oviductal fluid (SOF) supplemented with conjugated linoleic acid (CLA). Special interest was placed on gene expression linked to lipid metabolism and oocyte maturation. COCs were matured in different media: Medium 199 (M199 group), M199 with 100 μM CLA (M199 + CLA group), SOF (SOF group), and SOF with 100 μM CLA (SOF + CLA group). COCs matured with SOF showed a higher relative abundance of mRNA of quality indicators gremlin 1 (GREM1) and prostaglandin-endoperoxide synthase 2 (PTGS2) in oocytes, and GREM1 in cumulus cells compared with in the M199 group. SOF medium COCs had a higher relative abundance of fatty acid desaturase 2 (FADS2) compared with the M199 group, which is essential for lipid metabolism in oocytes. Furthermore, the abundance of stearoyl-coenzyme A desaturase 1 (SCD1) in oocytes matured with SOF was not influenced by the addition of CLA, whereas the relative abundance of SCD1 was reduced in M199 medium with CLA. We concluded that maturation in SOF medium results in a greater abundance of genes linked to quality and lipidic metabolism in oocytes, regardless of the addition of CLA.

Impact of letrozole co-treatment during ovarian stimulation on oocyte yield, embryo development, and live birth rate in women with normal ovarian reserve: secondary outcomes from the RIOT trial

STUDY QUESTION

Does letrozole (LZ) co-treatment during ovarian stimulation with gonadotropins for in IVF impact follicle recruitment, oocyte number and quality, embryo quality, or live birth rate (LBR)?

SUMMARY ANSWER

No impact of LZ was found in follicle recruitment, number of oocytes, quality of embryos, or LBR.

WHAT IS KNOWN ALREADY

Multi-follicle stimulation for IVF produces supra-physiological oestradiol levels. LZ is an aromatase inhibitor that lowers serum oestradiol thus reducing negative feedback and increasing the endogenous gonadotropins in both the follicular and the luteal phases, effectively normalizing the endocrine milieu during IVF treatment.

STUDY DESIGN, SIZE, DURATION

Secondary outcomes from a randomized, double-blind placebo-controlled trial (RCT) investigating once-daily 5 mg LZ or placebo during stimulation for IVF with FSH. The RCT was conducted at four fertility clinics at University Hospitals in Denmark from August 2016 to November 2018 and pregnancy outcomes of frozen-thawed embryo transfers (FET) registered until May 2023.

PARTICIPANTS/MATERIALS, SETTING, METHODS

One hundred fifty-nine women with expected normal ovarian reserve (anti-Müllerian hormone 8-32 nmol/l) were randomized to either co-treatment with LZ (n = 80) or placebo (n = 79). In total 1268 oocytes were aspirated developing into 386 embryos, and morphology and morphokinetics were assessed. One hundred twenty-nine embryos were transferred in the fresh cycle and 158 embryos in a subsequent FET cycle. The effect of LZ on cumulative clinical pregnancy rate (CPR), LBR, endometrial thickness in the fresh cycle, and total FSH consumption was reported.

MAIN RESULTS AND THE ROLE OF CHANCE

The proportion of usable embryos of retrieved oocytes was similar in the LZ group and the placebo group with 0.31 vs 0.36 (mean difference (MD) -0.05, 95% CI (-0.12; 0.03), P = 0.65). The size and number of aspirated follicles at oocyte retrieval were similar with 11.8 vs 10.3 follicles per patient (MD 1.5, 95% CI (-0.5; 3.1), P = 0.50), as well as the number of retrieved oocytes with 8.0 vs 7.9 oocytes (MD 0.1, 95% CI (-1.4; 1.6), P = 0.39) in the LZ and placebo groups, respectively. The chance of retrieving an oocyte from the 13 to 16 mm follicles at trigger day was 66% higher (95% CI (24%; 108%), P = 0.002) in the placebo group than in the LZ group, whilst the chance of retrieving an oocyte from the ≥17 mm follicles at trigger day was 50% higher (95% CI (2%; 98%), P = 0.04) in the LZ group than in the placebo group. The proportion of fertilized oocytes with two-pronuclei per retrieved oocytes or per metaphase II oocytes (MII) (the 2PN rates) were similar regardless of fertilization with IVF or ICSI with 0.48 vs 0.57 (MD -0.09, 95% CI (-0.24; 0.04), P = 0.51), and 0.62 vs 0.64 (MD -0.02, 95% CI (-0.13; 0.07), P = 0.78) in the LZ and placebo groups, respectively. However, the MII rate in the ICSI group was significantly lower with 0.75 vs 0.88 in the LZ vs the placebo group (MD -0.14, 95% CI (-0.22; -0.06), P = 0.03). Blastocysts on Day 5 per patient were similar with 1.5 vs 2.0, P = 0.52, as well as vitrified blastocysts per patient Day 5 with 0.8 vs 1.2 in (MD -0.4, 95% CI (-1.0; 0.2), P = 0.52) and vitrified blastocysts per patient Day 6 with 0.6 vs 0.6 (MD 0, 95% CI (-0.3; 0.3), P = 1.00) in the LZ vs placebo group, respectively. Morphologic evaluation of all usable embryos showed a similar distribution in 'Good', 'Fair', and 'Poor', in the LZ vs placebo group, with an odds ratio (OR) of 0.8 95% CI (0.5; 1.3), P = 0.68 of developing a better class embryo. Two hundred and ninety-five of the 386 embryos were cultured in an embryoscope. Morphokinetic annotations showed that the odds of having a high KIDscore™ D3 Day 3 were 1.2 times higher (CI (0.8; 1.9), P = 0.68) in the LZ group vs the placebo group. The CPR per transfer was comparable with 31% vs 39% (risk-difference of 8%, 95% CI (-25%; 11%), P = 0.65) in the LZ and placebo group, respectively, as well as CPR per transfer adjusted for day of transfer, oestradiol and progesterone levels at trigger, progesterone levels mid-luteal, and number of oocytes retrieved (adjusted OR) of 0.8 (95% CI (0.4; 1.6), P = 0.72). Comparable LBR were found per transfer 28% vs 37% (MD -9%, 95% CI (-26%; 9%), P = 0.60) and per randomized women 24% vs 30% (MD of -6%, CI (-22%; 8%), P = 0.60) in the LZ group and placebo group, respectively. Furthermore, 4.8 years since the last oocyte aspiration, a total of 287 of 386 embryos have been transferred in the fresh or a subsequently FET cycle, disclosing the cumulative CPR, which is similar with 38% vs 34% (MD 95% CI (8%; 16%), P = 0.70) in the LZ vs placebo group.

LIMITATIONS, REASONS FOR CAUTION

Both cleavage stage and blastocyst transfer and vitrification were permitted in the protocol, making it necessary to categorize their quality and pool the results. The study was powered to detect hormonal variation but not embryo or pregnancy outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

The similar utilization rate and quality of the embryos support the use of LZ co-treatment for IVF with specific indication as fertility preservation, patients with previous cancer, or poor responders. The effect of LZ on mature oocytes from different follicle sizes and LBRs should be evaluated in a meta-analysis or a larger RCT.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was received from EU Interreg for ReproUnion, Sjaelland University Hospital, Denmark, Ferring Pharmaceuticals, and Gedeon Ricther. Roche Diagnostics contributed with assays. A.P. has received grants from Ferring, Merck Serono, and Gedeon Richter, consulting fees from Preglem, Novo Nordisk, Ferring, Gedeon Richter, Cryos, & Merck A/S, speakers fees from Gedeon Richter, Ferring, Merck A/S, Theramex, & Organon, and travel support from Gedeon Richter. The remaining authors declare that they have no competing interests in the research or publication.

TRIAL REGISTRATION NUMBERS

NCT02939898 and NCT02946684.

Ovarian reserve in reproductive-aged patients with cancer before gonadotoxic treatment: a systematic review and meta-analysis

STUDY QUESTION

Does cancer itself, before any gonadotoxic treatment, affect ovarian function in reproductive-aged patients?

SUMMARY ANSWER

Our study revealed that women with cancer may have decreased ovarian reserve markers even before cancer therapy.

WHAT IS KNOWN ALREADY

With the field 'oncofertility' improving rapidly, cancer therapy-mediated ovarian damage is well characterized. However, there is a controversy about whether cancer itself affects ovarian function before gonadotoxic treatment.

STUDY DESIGN SIZE DURATION

We conducted a systematic meta-analysis investigating the association between cancer and ovarian function prior to gonadotoxic treatment. Titles or abstracts related to ovarian reserve (e.g. anti-Müllerian hormone (AMH), antral follicle count (AFC), or basal follicle-stimulating hormone (FSH)) combined with titles or abstracts related to the exposure (e.g. cancer*, oncolog*, or malignan*) were searched in PubMed, Embase, and Web of Science databases from inception to 1 February 2022.

PARTICIPANTS/MATERIALS SETTING METHODS

We included cohort, case-control, and cross-sectional studies in English that examined ovarian reserve in reproductive-aged patients (18-45 years) with cancer compared to age-matched controls before cancer treatment. The quality of the included studies was assessed by ROBINS-I. Fixed or random effects were conducted to estimate standard or weighted mean difference (SMD or WMD, respectively) and CI. Heterogeneity was assessed by the Q test and I² statistics, and publication bias was evaluated by Egger's and Begg's tests.

MAIN RESULTS AND THE ROLE OF CHANCE

The review identified 17 eligible studies for inclusion. The results showed that cancer patients had lower serum AMH levels compared to healthy controls (SMD = -0.19, 95% CI = -0.34 to -0.03, P = 0.001), especially women with hematological malignancies (SMD = -0.62, 95% CI = -0.99 to -0.24, P = 0.001). The AFC was also decreased in patients with cancer (WMD = -0.93, 95% CI = -1.79 to -0.07, P = 0.033) compared to controls, while inhibin B and basal FSH levels showed no statistically significant differences.

LIMITATIONS REASONS FOR CAUTION

Serum AMH and basal FSH levels in this meta-analysis showed high heterogeneity, and the small number of studies contributing to most subgroup analyses limited the heterogeneity analysis. Moreover, the studies for specific cancer subtypes may be too small to draw conclusions; more studies are needed to investigate the possible impact of cancer type and stage on ovarian function.

WIDER IMPLICATIONS OF THE FINDINGS

Our study confirmed the findings that cancer per se, especially hematological malignancies, negatively affects serum AMH level, and AFC values of reproductive-aged women. However, the lower AMH levels and AFC values may also be due to the changes in ovarian physiology under oncological conditions, rather than actual lower ovarian reserves. Based on the meta-analysis, clinicians should raise awareness about the possible need for personalized approaches for young women with cancer who are interested in pursuing fertility preservation strategies before anticancer treatments.

STUDY FUNDING/COMPETING INTERESTS

This work was financially supported by the National Natural Science Foundation of China (nos 81873824, 82001514, and 81902669) and the Applied Basic Research Program of Wuhan Municipal Bureau of Science and Technology (2019020701011436). The authors declare that they have no conflicts of interest.

REGISTRATION NUMBER

PROSPERO (CRD42021235954).

The effect of aromatase inhibitor on controlled ovarian stimulation for oocyte cryopreservation in adolescent and young cancer patients

AIM

To determine the impact of aromatase inhibitor (AI) use in oocyte cryopreservation among Japanese adolescent and young adult (AYA) cancer patients for fertility preservation, we evaluated the oocyte cryopreservation outcomes following AI therapy in combination with the follicular phase start (FPS) and random start (RS) protocols.

METHODS

This retrospective study included 81 cycles of controlled ovarian stimulation (COS) among 73 AYA patients with cancer who underwent oocyte cryopreservation to maintain fertility. The outcome measures were the total number of matured oocytes that were retrieved and cryopreserved, as well as their maturation rates. The AI (+) and AI (-) groups were compared using the RS and FPS protocols.

RESULTS

Our results showed that the combined use of AI and COS decreases serum E2 levels and maintains the number of retrieved and cryopreserved mature oocytes. We also confirmed the efficacy of the RS protocol, which was found to have comparable outcomes to that of the FPS protocol in both AI (+) and AI (-) groups.

CONCLUSION

The combined use of AI and COS is beneficial for oocyte cryopreservation in patients with estrogen-sensitive cancer, regardless of the menstrual cycle phase of COS initiation.

Outcomes after assisted reproductive technology in women with cancer: a systematic review and meta-analysis

STUDY QUESTION

What are the associations between a history of cancer and outcomes after ART?

SUMMARY ANSWER

Compared to women without cancer, on average, women with cancer had a lower return for embryo transfer and a lower likelihood of clinical pregnancy and live birth after ART.

WHAT IS KNOWN ALREADY

Small, single-institution studies have suggested that cancer and its treatment may negatively affect ART outcomes.

STUDY DESIGN, SIZE, DURATION

We conducted a systematic review with meta-analysis of studies comparing ART outcomes between women with and without cancer. PubMed, Embase and Scopus were searched for original, English-language studies published up to June 2021.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Inclusion criteria required reporting of ART outcomes after controlled ovarian stimulation (COS) among women with a history of cancer compared to women without cancer who used ART for any indication. Outcomes of interest ranged from duration of COS to likelihood of live birth after embryo transfer. Random-effects meta-analysis was used to calculate mean differences and odds ratios (ORs) with 95% CIs and 95% prediction intervals (PIs). We assessed heterogeneity by age-adjustment, referent group indication for ART, study location and among women with breast cancer and women who initiated ART before cancer treatment. We used visual inspection, Egger's test and the trim-and-fill method to assess funnel plot asymmetry.

MAIN RESULTS AND THE ROLE OF CHANCE

Of 6094 unique records identified, 42 studies met inclusion criteria, representing a median per study of 58 women with cancer (interquartile range (IQR) = 159) and 114 women without cancer (IQR = 348). Compared to women without cancer, on average, women with cancer had a lower return for embryo transfer (OR: 0.22; 95% CI: 0.07, 0.74; 95% PI: 0.00, 64.98); lower likelihood of clinical pregnancy (OR: 0.51; 95% CI: 0.35, 0.73; 95% PI: 0.19, 1.35); and lower likelihood of live birth (OR: 0.56; 95% CI: 0.38, 0.83; 95% PI: 0.19, 1.69). Substantial among-study heterogeneity was observed for COS duration, gonadotropin dose, cycle cancellation, total oocytes and mature oocytes. Fertilization percentage showed less heterogeneity, but study-specific estimates were imprecise. Similarly, number of embryos showed less heterogeneity, and most studies estimated minimal differences by cancer history. Funnel plot asymmetry was observed for estradiol peak and oocyte maturation percentage.

LIMITATIONS, REASONS FOR CAUTION

Appreciable confounding is possible in 11 studies that lacked adequate control for group differences in age, and among-study heterogeneity was observed for most outcomes. Lack of data limited our ability to assess how cancer clinical factors (e.g. cancers other than breast, cancer stage and treatment) and ART cycle characteristics (e.g. fresh versus frozen embryo transfers and use of gestational carriers) may affect outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Women with cancer may be less likely to achieve pregnancy and live birth after embryo transfer. Further examination of reproductive outcomes and sources of heterogeneity among studies is warranted to improve evidence of the expected success of ART after a cancer diagnosis.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported in part by R01 CA211093 and P30 ES010126. C.M. was supported by the University of North Carolina Lineberger Cancer Control Education Program (T32 CA057726) and the National Cancer Institute (F31 CA260787). J.A.R.-H. was supported by the National Cancer Institute (K08 CA234333, P30 CA016672). J.A.R.-H. reports receiving consulting fees from Schlesinger Group and Guidepoint. The remaining authors declare no competing interests.

REGISTRATION NUMBER

N/A.

The impact of letrozole on oocyte quality in assisted reproductive technology (ART); a randomized double-blind clinical trial

OBJECTIVE

To examine the effect of letrozole on oocyte quality and pregnancy outcome in assisted reproductive technology (ART).

METHODS

This double blind placebo controlled clinical trial was conducted in Vali-Asr Infertility Center. Infertile women candidate for IVF that underwent antagonist protocol were selected. Eligible women randomly allocated into treatment (letrozole/Let group) and control (placebo) group. Participants received letrozole 5 mg/day or placebo at the time of gonadotropin start until trigger day in the same manner. Number of oocyte retrieved, metaphase II oocyte number, high grade oocyte number (G1), high quality embryo, Chemical and clinical pregnancy rate and OHSS (ovarian hyperstimulation syndrome) rate was recorded. 216 infertile women (104 in letrozole and 112 in the control group) were evaluated.

RESULTS

In the Let group estradiol level was significantly lower (p_value < .001) and testosterone significantly higher than in the control group (p_value = .02). The number of retrieved oocytes, MII oocytes, G1 oocytes, and 2PN was significantly lower in the Let group (p < .05). No significant difference was found in the day of stimulation, total gonadotropin dose, OHSS rate, and clinical pregnancy rate between the two groups (p > 0.05).

CONCLUSIONS

According to the results, letrozole may reduce oocyte quality and cause poor IVF outcomes as well.

Oocyte Quality Assessment in Breast Cancer: Implications for Fertility Preservation

BACKGROUND

The aim of this study was to evaluate the effects of breast cancer on the ovarian response and on oocyte quality following controlled ovarian hyperstimulation (COH).

METHODS

This retrospective case-control study evaluated the effects of breast cancer on the ovarian response and on the oocyte quality. Oncological patients with breast cancer undergoing controlled ovarian stimulation cycles for fertility preservation, and age- and date-matched controls undergoing COH for in vitro fertilization (IVF) for male or tubal factor infertility were included in the study. Two hundred and ninety-four women were enrolled: 105 affected by breast cancer and 189 healthy women in the control group. Both groups were comparable in terms of age, BMI, and AMH value. Maximal estradiol levels on the triggering day, duration of stimulation, total amount of gonadotropins administered, number of oocytes retrieved, rate of metaphase 2 oocyte production, and numbers of immature and dysmorphic oocytes were analyzed.

RESULTS

Considering factors influencing the oocyte quality, such as age, BMI, AMH, duration of stimulation, E2 level on the triggering day, total FSH cumulative dose, stage, histotype, BRCA status, and hormone receptors, the univariate and multivariate analyses identified breast cancer as a risk factor for the presence of dysmorphic oocytes.

CONCLUSIONS

The diagnosis of breast cancer does not seem to be associated with the impairment of the ovarian reserve, but is linked to a worsening oocyte quality.

Hormone concentrations of dominant follicles in the TALES randomized controlled trial comparing letrozole with tamoxifen

BACKGROUND

In this secondary analysis of the TAmoxifen or Letrozole in Estrogen Sensitive tumors (TALES) trial, we aimed to investigate if concurrent administration of letrozole vs. tamoxifen vs. no added treatment affects hormonal composition and size of stimulated ovarian follicles.

METHODS

TALES is a randomized controlled trial of IVF stimulation for estrogen receptor (ER)-positive breast cancer patients stimulated with gonadotropins and administered concurrent tamoxifen 20 mg or letrozole 5 mg. We analyzed estradiol (E2), testosterone (T), progesterone (P4), follicle stimulating hormone (FSH), luteinizing hormone (LH), and anti-Mullerian hormone (AMH). We used ANOVA/Kruskal-Wallis, logistic, and linear regression models to examine differences in follicular hormone levels, size, and mature oocyte yield between trial arm.

RESULTS

We included data from total 246 follicles (94 letrozole, 82 tamoxifen, and 70 control) from 123 unique participants. E2 was lower (letrozole 187.4, tamoxifen 1026.0, control 821.5 ng/mL, p < 0.01) and T was higher (letrozole 2489, tamoxifen 571, and control 504 ng/mL, p < 0.03) in the letrozole group compared to tamoxifen and control groups, while other hormone levels and follicle size were similar across groups. There were no significant differences in hormone concentrations within the follicle between tamoxifen and control arms. On multivariate logistic regression, there was no significant association of mature oocyte yield by follicle size, hormone levels, or trial arm.

CONCLUSIONS

Concurrent administration of letrozole with gonadotropins affects follicular E2 and T concentrations compared to tamoxifen/control. Tamoxifen was not associated with any differences in hormone concentrations within the follicle. Mature oocyte yield was similar across groups.

What should be done in terms of fertility preservation for patients with cancer? The French 2021 guidelines

AIM

To provide practice guidelines about fertility preservation (FP) in oncology.

METHODS

We selected 400 articles after a PubMed review of the literature (1987-2019).

RECOMMENDATIONS

Any child, adolescent and adult of reproductive age should be informed about the risk of treatment gonadotoxicity. In women, systematically proposed FP counselling between 15 and 38 years of age in case of treatment including bifunctional alkylating agents, above 6 g/m2 cyclophosphamide equivalent dose (CED), and for radiation doses on the ovaries ≥3 Gy. For postmenarchal patients, oocyte cryopreservation after ovarian stimulation is the first-line FP technique. Ovarian tissue cryopreservation should be discussed as a first-line approach in case of treatment with a high gonadotoxic risk, when chemotherapy has already started and in urgent cases. Ovarian transposition is to be discussed prior to pelvic radiotherapy involving a high risk of premature ovarian failure. For prepubertal girls, ovarian tissue cryopreservation should be proposed in the case of treatment with a high gonadotoxic risk. In pubertal males, sperm cryopreservation must be systematically offered to any male who is to undergo cancer treatment, regardless of toxicity. Testicular tissue cryopreservation must be proposed in males unable to cryopreserve sperm who are to undergo a treatment with intermediate or severe risk of gonadotoxicity. In prepubertal boys, testicular tissue preservation is: - recommended for chemotherapy with a CED ≥7500 mg/m2 or radiotherapy ≥3 Gy on both testicles. - proposed for chemotherapy with a CED ≥5.000 mg/m2 or radiotherapy ≥2 Gy. If several possible strategies, the ultimate choice is made by the patient.

Efficacy and safety of controlled ovarian hyperstimulation with or without letrozole for fertility preservation in breast cancer patients: A multicenter retrospective study

INTRODUCTION

Fertility preservation (FP) is recommended in young breast cancer (BC) patients before (neo)adjuvant treatment. Letrozole-associated controlled ovarian hyperstimulation (LetCOH) is used worldwide to collect mature oocytes for FP, but its efficacy and safety compared to conventional protocols (cCOH) are still debated.

AIMS

To compare efficacy and safety of FP procedure using LetCOH or cCOH in BC patients in terms of oocyte maturation rate and disease-free survival rates after at least two years of follow-up.

METHODS

This multicenter retrospective study compared outcomes of 107 cycles in 97 non-metastatic BC patients aged ≤40 years who underwent cCOH (n = 56) or LetCOH (n = 41) for FP in CHU-Lille and Erasme Hospital, respectively, between December 2012 and January 2017.

RESULTS

Patients and oncological characteristics were similar except for tumor size and HER2 status which were less favorable in the LetCOH group. Patients underwent adjuvant chemotherapy in 96.4% and 48.8% of the cases in cCOH and LetCOH groups, respectively. Hence, 51.2% of LetCOH patients underwent neoadjuvant chemotherapy (p < 0.001). Estradiol peak at ovulation trigger was lower in LetCOH compared to cCOH group while oocyte maturation rates were significantly higher (p < 0.001), without impacting the final number of mature oocytes collected. Seven and four patients relapsed in LetCOH and cCOH groups, respectively, and one patient died in each group after a median follow-up of four years.

CONCLUSION

LetCOH is as effective as cCOH for FP. At this time point, there were no safety concerns regarding cCOH in the adjuvant setting but a longer follow-up is warranted.

Clinical outcome of embryo cryopreservation in Japanese breast cancer patients: pregnancy rates after transfer of thawed embryos

PURPOSE

To examine pregnancy outcomes after cryopreserved embryo transfer (ET) in breast cancer patients and to investigate the effect of controlled ovarian hyperstimulation (COH) as well as that of aromatase inhibitor (AI) administration and of the random start (RS) ovarian stimulation method.

METHODS

This retrospective study covered 126 patients who underwent embryo cryopreservation between 2010 and 2019. Thirty-one patients underwent frozen embryo transfer (FET), and we examined resulting pregnancy rates (PRs) and live birth rates (LBRs) in those who did and did not undergo COH and in relation to the AI and RS methods.

RESULTS

PR and LBR per patient were higher among patients who underwent COH than among those who did not. PR per ET did not differ from that documented for non-cancer infertility patients, after adjustment for age. The PR and LBR did not differ between use and non-use of AI (27.8% vs 35.2%). In addition, there was no significant difference in the PR or LBR between RS and conventional start ovarian stimulation (33.3% vs 30.8%). No prenatal fetal abnormalities were observed in 8 cases (including 5 AI cases and 2 RS cases).

CONCLUSIONS

This study showed that the outcome of FET after FP was equivalent to that seen in non-cancer patients. Further, neither use of AI nor the RS method influenced LBR. COH including use of AI and the RS method are useful in FP for collecting and freezing many embryos within a short period and for increasing the per patient LBR after cancer treatment.

Live birth after letrozole as an adjunct to follicle-stimulating hormone versus follicle-stimulating hormone alone for ovarian stimulation in in vitro fertilisation cycles-study protocol for a randomised controlled trial

INTRODUCTION

In vitro fertilisation (IVF) is an effective infertility treatment but the live birth rate remains unsatisfactory. Ovarian stimulation by follicle-stimulating hormone (FSH) is routinely used in IVF and the resulting high serum estradiol levels may impair oocyte/embryo quality and endometrial receptivity. Letrozole, an aromatase inhibitor, can reduce serum estradiol levels following ovarian stimulation. We aim to test the hypothesis that co-treatment with letrozole reduces supraphysiological serum estradiol levels and improves endometrial receptivity, leading to a higher live birth rate of IVF. We are conducting a randomised controlled trial (RCT) to evaluate whether letrozole as an adjunct to FSH in IVF is superior to FSH alone in the live birth rate of fresh embryo transfer.

METHODS/DESIGN

This is an open-label randomised controlled superiority trial being performed in two assisted reproduction centres in China. Infertile women who have antral follicle count (AFC) before ovarian stimulation or on day 5 of ovarian stimulation ≥15 are randomly allocated in a 1:1 ratio to receive either letrozole and FSH or FSH alone in a GnRH antagonist protocol. Recruited women follow the standard operating procedures of the two centres. The primary outcome is the live birth rate of the fresh embryo transfer. Stimulation parameters, maternal side effects and obstetric and perinatal complications are secondary outcomes. The planned sample size is 900, i.e. 450 per group.

DISCUSSION

The present study is the first multicentre randomised study to compare the live birth rate of the fresh embryo transfer following ovarian stimulation by letrozole and FSH versus FSH alone in women with anticipated high ovarian responses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02912988 . Registered on September 23, 2016. This trial protocol is version 2.0.

Effect of letrozole on follicular fluid steroids concentrations in cancer patients undergoing oocytes cryopreservation

PURPOSE

To investigate the impact of letrozole administration on follicular steroid hormones during controlled ovarian hyperstimulation for fertility preservation.

METHODS

One hundred and nineteen women with cancer undergoing oocytes retrieval for fertility preservation were recruited. All women underwent ovarian hyperstimulation according to a random start protocol. Those with hormone-sensitive tumors also received letrozole, an aromatase inhibitor aimed at keeping peripheral estrogen levels low. At the time of oocytes retrieval, a sample of follicular fluid was collected and frozen. All samples were assayed concomitantly after thawing, by liquid chromatography tandem mass spectrometry. The concentration of 15 steroid hormones was determined and results were compared between women who did and did not receive letrozole.

RESULTS

Fifty-two women were treated with letrozole, while 67 were not. Statistically significant differences emerged for 12 of the 15 tested steroids. They were the following: cortisol, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), estradiol, androstenedione, testosterone, dihydrotestosterone (DHT), 17-hydroxyprogesterone, progesterone and corticosterone. The most striking differences were observed for testosterone that showed a more than 200-time increase in women receiving letrozole. Estradiol was conversely reduced to a third.

CONCLUSIONS

The endocrine microenvironment surrounding oocytes is markedly perturbed by the concomitant assumption of letrozole. Robust clinical evaluation is pressingly needed to rule out any detrimental effect on the chance of live birth with the use of these oocytes.

Gonadotropin-Releasing Hormone Agonist Versus Recombinant Human Chorionic Gonadotropin Triggering in Fertility Preservation Cycles

The purpose of this research is to study the efficacy of GnRH-a versus r-hCG triggering in patients who go through fertility preservation cycles. This retrospective cohort study was performed in a tertiary university-affiliated medical center. It includes 191 patients undergoing fertility preservation cycles between May 2013 and September 2018, in which ovulation was induced by either GnRH-a or r-hCG. Main outcome measures were number and rate of mature oocyte. Among treatment cycles with medical indication, GnRH agonist significantly increases the odds for high mature rate by 3.55 (1.30-9.66), while in treatment cycles with social indication, there is no significant effect of the triggering agent. An advantage for GnRH-a triggering was observed in medically indicated preservation cycles.

Female fertility preservation: Impact of cancer on ovarian function and oocyte quality

OBJECTIVE

To evaluate the influence of cancer on ovarian response and oocyte quality in controlled ovarian hyperstimulation (COH).

METHODS

This prospective study conducted at the Physiopathology of Reproduction and Andrology Unit of Sandro Pertini Hospital enrolled 82 cancer patients undergoing controlled ovarian stimulation (COH) cycles for fertility preservation, and age- and date-matched controls undergoing COH for in vitro fertilization for male-factor infertility from June 2016 to November 2019. The interventions performed were COH, oocyte retrieval, and quality evaluation. Main outcome measures were maximal estradiol levels on the day of human chorionic gonadotropin administration, duration of stimulation, total amount of gonadotropins administered, number of oocytes retrieved, and rates of metaphase 2 oocytes and abnormal oocytes. All data were analyzed using the Statistical Package for the Social Sciences (IBM Corp., Armonk, NY, USA) 22.0.

RESULTS

Intergroup comparisons (82 cancer patients and 180 patients in control group) showed a significant difference in ovarian response, especially for a significant higher number of abnormal oocytes in cancer patients (P < 0.0001). Regression analysis to assess the influence of the neoplastic process, regardless of the type, on ovarian response showed an effect on the main outcome measured due to cancer itself.

CONCLUSION

Cancer influences the ovarian response, particularly the oocyte quality, during COH performed for fertility preservation.

Controlled ovarian hyperstimulation for fertility preservation in women with breast cancer: Practical issues

In Korean women, a westernized lifestyle is associated with an increased risk of breast cancer. Fertility preservation has become an increasingly important issue for women with breast cancer, in accordance with substantial improvements in survival rate after cancer treatment. The methods of controlled ovarian hyperstimulation (COH) for fertility preservation in breast cancer patients have been modified to include aromatase inhibitors to reduce the potential harm associated with increased estradiol levels. Random-start COH and dual ovarian stimulation are feasible options to reduce the total duration of fertility preservation treatment and to efficiently collect oocytes or embryos. Using a gonadotropin-releasing hormone agonist as a trigger may improve cycle outcomes in breast cancer patients undergoing COH for fertility preservation. In young breast cancer patients with BRCA mutations, especially BRCA1 mutations, the possibility of diminished ovarian reserve may be considered, although further studies are necessary. Herein, we review the current literature on the practical issues surrounding COH for fertility preservation in women with breast cancer.

Efficacy and Safety of Controlled Ovarian Stimulation With or Without Letrozole Co-administration for Fertility Preservation: A Systematic Review and Meta-Analysis

Background: The co-administration of letrozole during controlled ovarian stimulation (COS) with gonadotropins is used to limit the potentially harmful effects of a supra-physiological rise in estrogen levels on hormone-sensitive cancers. However, the efficacy and safety of adding letrozole to COS remain debated.

Methods: This is a systematic review and meta-analysis of published studies that compared the efficacy and safety of COS with co-administration of letrozole vs. COS without letrozole in all patient populations. A secondary analysis was done including only the studies in breast cancer patients. The primary efficacy endpoint was the number of retrieved mature Metaphase II (MII) oocytes. Secondary efficacy and safety endpoints were total number of oocytes, maturation rate, fertilization rate, number of cryopreserved embryos, peak estradiol levels, progesterone levels, and total gonadotropin dose. Data for each endpoint were reported and analyzed thorough mean ratio (MR) with 95% confidence interval (CI).

Results: A total of 11 records were selected including 2,121 patients (990 patients underwent COS with letrozole and 1,131 COS without letrozole). The addition of letrozole to COS did not have any negative effect on the number of mature oocytes collected (MR = 1.00, 95% CI = 0.87–1.16; P = 0.967) and the other efficacy endpoints. COS with letrozole was associated with significantly decreased peak estradiol levels (MR = 0.28, 95% CI = 0.24–0.32; P < 0.001). Similar results were observed in the secondary analysis including only breast cancer patients.

Conclusions: These findings are reassuring on the efficacy and safety of COS with gonadotropins and letrozole and are particularly important for fertility preservation in women with hormone-sensitive cancers.

Aromatase Inhibitors for Ovarian Stimulation in Patients with Breast Cancer

BACKGROUND

Breast cancer is the most common malignancy diagnosed in women, and its treatment has a high probability of loss of fertility. Oocyte vitrification is the most commonly used technique to preserve fertility before starting oncological treatment. Aromatase inhibitors induce hypoestrogenemia while promoting the release of gonadotropins and constitute an alternative drug for ovarian stimulation in patients with breast cancer.

OBJECTIVE

In this mini-review, we update and describe the current status of aromatase inhibitor use in controlled ovarian stimulation for oocyte vitrification in patients with breast cancer.

RESULTS

Aromatase inhibitors are commonly used in combination with gonadotropins for ovarian stimulation in patients with breast cancer who preserve their fertility through oocyte vitrification. They achieve similar ovarian responses as conventional ovarian stimulation protocols in regards to the number of oocytes, and no additional complications after their use have been reported. Furthermore, aromatase inhibitors seem to be safe not only for offspring, as no more congenital defects occur in newborns from pregnancies achieved after their use, but also for the patients, as no more malignancy recurrence or increased mortality was found in cohort studies.

CONCLUSION

Aromatase inhibitors are elective drugs for ovarian stimulation in patients with breast cancer who decide to preserve their fertility through oocyte vitrification.