Random-start ovarian stimulation with aromatase inhibitor for fertility preservation in women with Japanese breast cancer

mTOR inhibitors potentially preserve fertility in female patients with haematopoietic malignancies: a narrative review

Haematologic malignancies are considered among the more common adolescent and young adult (AYA) cancers. Many female AYA patients with haematopoietic malignancies face impaired fertility. Haematologic malignancies patients tend to be treated with more aggressive systemic chemotherapy than that of solid tumours. In adult women, treatment-related contraception causes age-related fertility loss. Graft-versus-host disease (GVHD) after allogeneic haematopoietic stem cell transplantation is associated with decreased fertility. Ovarian cryopreservation is often indicated for haematopoietic malignancies; however, follicle loss associated with ovarian cryopreservation and ovarian minimal residual disease, which result in the withdrawal of the transplantation, are important issues. These problems may not be fully addressed by conventional methods of fertility preservation, such as oocyte, embryo, and ovarian cryopreservation, leaving room for research into new treatment approaches, such as fertility preservation drugs. In recent years, preclinical studies have shown that mTOR inhibitors may preserve chemotherapy-induced follicular loss, may have follicle-preserving effects on follicle loss associated with cryopreservation and transplantation of ovarian tissue, may have fertility-preserving effects on aging-related infertility. Clinical studies have shown that mTOR inhibitors may have the potential for indirect fertility preservation by controlling GVHD, have a limited anti-tumor effect against haematopoietic malignancies. The purpose of this article is to outline the various issues faced by female survivors of haematopoietic malignancies and discuss the potential of mTOR inhibitors as a safe treatment option. Based on current research, mTOR inhibitors seem promising and innovative fertility preservation agents regarding preclinical conditions, and further study, including clinical trials, should be expected.

Programming the onset of ovarian stimulation: from early follicular phase start to oral contraceptive pill, to luteal phase E2, Duostim, and random start oral contraceptive protocols

Ovarian stimulation has been the single most efficient measure ever taken in assisted reproductive technology for improving outcomes by harvesting multiple oocytes and ultimately, embryos. Today, ovarian stimulation protocols consist of administrating exogenous gonadotropins to override the natural mechanisms that control the ovulatory quota to one in humans. For practicality issues, there have been numerous attempts to control, or "program," when ovarian stimulation is initiated to improve functionality and in turn efficacy for assisted reproductive technology programs. The different options for controlling the onset of ovarian stimulation currently available are discussed here, as well as the novel possibility of using progestins for blocking premature ovulation.

Random start ovarian stimulation before gonadotoxic therapies in women with cancer: a systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to quantify the effect of random start ovarian stimulation (RSOS) compared with conventional start ovarian stimulation (CSOS) in cancer patients before gonadotoxic treatment. The final analytical cohort encompassed 688 RSOS and 1076 CSOS cycles of cancer patients before gonadotoxic treatment. Eleven studies were identified by database searches of MEDLINE, Cochrane Library and cited references. The primary outcomes of interest were the number of oocytes and mature oocytes collected, the number of embryos cryopreserved and the metaphase II (MII)-antral follicle count (AFC) ratio. The studies were rated from medium to high quality (from 6 to 9) according to the Newcastle-Ottawa Quality Assessment Scale. The two protocols resulted in similar numbers of oocytes collected, MII oocytes, embryos available for cryopreservation and comparable MII-AFC and fertilization rates. The duration of ovarian stimulation was longer (standardized mean difference [SMD] 0.35, 95% CI 0.09 to 0.61; P = 0.009) and gonadotrophin consumption was higher (SMD 0.23, 95% CI 0.06 to 0.40; P = 0.009) in RSOS compared with CSOS. This systematic review and meta-analysis show that the duration of stimulation is longer, and the total gonadotrophin consumption is higher in cancer patients undergoing RSOS compared with those undergoing CSOS, with no significant effect on mature oocyte yield.

A reappraisal of ovarian stimulation strategies used in assisted reproductive technology

Ovarian stimulation is a fundamental step in assisted reproductive technology (ART) with the intention of inducing ovarian follicle development prior to timed intercourse or intra-uterine insemination and facilitating the retrieval of multiple oocytes during a single in vitro fertilization (IVF) cycle. The basis of ovarian stimulation includes the administration of exogenous gonadotropins, with or without pre-treatment with oral hormonal therapy. Gonadotropin-releasing hormone agonist or antagonist is given in addition to the gonadotropins to prevent a premature rise of endogenous luteinizing hormone that would in turn lead to premature ovulation. With the advancement in technology, various stimulation protocols have been devised to cater for different patient needs. However, ovarian hyperstimulation syndrome and its serious complications may occur following ovarian stimulation. It is also evident that suboptimal ovarian stimulation strategies may have a negative impact on oogenesis, embryo quality, endometrial receptivity, and reproductive outcomes over recent years. This review describes the various forms of pre-treatment for ovarian stimulation and stimulation protocols, and aims to provide clinicians with the latest available evidence.

Ovarian stimulation and oocyte cryopreservation in females with cancer

PURPOSE OF REVIEW

We reviewed the most recent developments including the safety and effectiveness data and success rates in individualized ovarian stimulation protocols for adult and postpubertal females with cancer.

RECENT FINDINGS

In women with breast cancer, aromatase inhibitor- and tamoxifen-supplemented stimulation protocols increase the margin of safety by limiting estrogen exposure. The outcomes of ovarian stimulation appear similar between cancer and noncancer populations, even with the recently developed random-start protocols, which allow initiation of ovarian stimulation anytime during the menstrual cycle. Based on lower anti-Mullerian hormone levels and primordial follicle density, carriers of BRCA pathogenic variants ( BRCApv ) have decreased ovarian reserve in comparison to women without those variants and may lose larger portion of their ovarian reserve post chemotherapy. Oocyte cryopreservation is also emerging as a suitable fertility preservation approach for selected postpubertal girls as young as 12 years of age.

SUMMARY

Individualized ovarian stimulation approaches combined with improvements in cryopreservation techniques increased the success and safety margin to preserve fertility with oocyte freezing. Women with BRCApv , on the other hand, may be at disadvantage as they have lower ovarian reserve and may lose larger portion of their ovarian reserve post chemotherapy compared to women who do not carry these variants.

Evaluation of the relationship between vitamin D levels with oocyte quality in breast cancer women: a cross-sectional study

Recent evidence suggests that vitamin D deficiency could play an important role in the development of non-skeletal diseases, including cancer. Vitamin D also affects the function of the reproductive system. In the present study, the relationship between 25(OH)D levels with oocyte quality in Breast Cancer (BC) women and control group have been investigated. After initial evaluations, ovarian stimulation began with the GnRH antagonist protocol in the BC group (N = 16) and control group (N = 16). The serum and follicular fluid (FF) 25(OH)D levels were measured at the time of oocyte retrieval and their relationship to oocyte quality was examined. The mean levels of serum and FF 25(OH)D in BC women were significantly lower than in the control group (22.26 ± 7.98 vs. 29.61 ± 9.12, P = 0.02, 21.65 ± 7.59 vs. 28.00 ± 9.05, P = 0.04, respectively). There was a significant correlation between the levels of 25(OH)D in FF and serum in BC women (r = 0.873, P < 0.001). But there was no correlation between the serum or FF 25(OH)D levels with the parameters related to oocytes (P > 0.05). In the BC women, the number of dysmorph and highly dysmorph oocytes was higher than in the control group (P < 0.001). Women with BC referring to infertility centers for fertility preservation are more likely to be deficient in serum 25(OH)D level; this subsequently affects the FF 25(OH)D level. However, serum and FF 25(OH)D levels may not be suitable indicators for examining maturity and quality of oocytes in terms of morphology in BC women, and the poor morphological quality of oocytes in BC women may be due to other factors.

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.

Retrospective study of influencing factors on the outcomes of luteal phase stimulation in patients with dual stimulation

Background

Dual/double stimulation (DS) is an ovarian stimulation strategy that has emerged in recent years; it is characterized by two rounds of ovarian stimulation and oocyte retrieval in the same menstrual cycle. DS can greatly shorten the time required to obtain valid embryos in assisted reproduction. For fertility preservation, DS can speed up oocyte storage process. However, factors influencing luteal phase ovarian stimulation (LPS) outcomes in DS have not been elucidated.

Methods

A total of 156 cycles from 78 cases were studied. Patients were grouped and analyzed according to their follicular phase ovarian stimulation (FPS) types. Female ages, ovarian stimulation protocols, number of oocytes retrieved, embryo quality were recorded. Comparisons of outcomes were conducted between different groups.

Results

Our study found that LPS obtained similar outcomes to follicular phase stimulation (FPS), and that the choice of FPS protocol affected the efficiency of LPS, the antagonist protocol and progestin-primed ovarian stimulation (PPOS) protocol resulted in better embryo outcomes in LPS. In LPS of DS, sufficient stimulation duration was the guarantee of embryo quality (number of available embryos: β = 0.145, 95% CI [0.078-0.211], P = 0.000; number of high-quality embryos: β = 0.114, 95% CI [0.057-0.171], P = 0.000).

Discussion

This study provided ideas for the precise use of DS. We suggest to further expand the sample size of DS in the future, conduct prospective controlled studies, unify the sample size of each subgroup, include the ovarian reserve of patients in the grouping basis, and exclude the influence of male factors. We hope that this study will help further refinement of DS so as to maximize patient benefits from it.

Conclusion

When the DS strategy is considered in the follicular phase, the antagonist protocol and PPOS protocol are more recommended for better embryo outcomes in LPS. During LPS, adequate ovarian stimulation duration is the most important guarantee for LPS efficiency.

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.

Pregnancy after breast cancer in BRCA1/2 mutation carriers

Background

Often young women affected with BRCA1/2 positive breast cancer have not finished or even not started their childbearing before the onset of the disease. The aim of our mini-review is to summarize state of art knowledge on pregnancy after breast cancer in BRCA1/2 carriers.

Methods

A broad review of the literature was conducted using MEDLINE (via PubMed) for relevant articles published.

Main body of the abstract

This review summarizes the impact of different cytotoxic agents on a fertility, fertility preservation, maternal and fetal prognosis after pregnancy in breast cancer survivors with BRCA1/2.

Conclusion

According to the existing literature evidence pregnancy after therapy for breast cancer in BRCA carriers is safe for the mother and offspring, but patients’ needs, oncofertility counseling and fertility-sparing strategy should be carefully planned before starting the cytotoxic treatment.

Fertility preservation for women with breast cancer before chemotherapy: a systematic review and meta-analysis

The preservation of fertility in women of childbearing age with breast cancer is challenging since the time for ovarian stimulation is restricted and only a limited amount of oocytes can be retrieved before gonadotoxic therapies. The aim of this meta-analysis is to evaluate the fertility preservation outcomes after ovarian stimulation with various protocols in women with breast cancer. PubMed, Embase, and the Cochrane Library were searched. Studies comparing the outcomes of women with breast cancer receiving random-start ovarian stimulation or conventional protocol; single or double ovarian stimulation cycles; and coadministration of aromatase inhibitors or tamoxifen were included. Twenty-two studies were included. Random-start ovarian stimulation resulted in a comparable number of retrieved oocytes to the conventional protocol. Two ovarian stimulation cycles had significantly higher numbers of total retrieved oocytes than one cycle (mean difference: 7.91, 95% CI: 3.42-12.4). Coadministration of letrozole and tamoxifen showed similar results of retrieved oocytes to those without. A significantly lower peak serum estradiol level was observed in letrozole-based groups than in letrozole-free groups. In conclusion, our study indicated that implementing random-start protocols to shorten the duration of waiting for ovarian stimulation, applying two ovarian stimulation cycles, and coadministering letrozole can lead to more desirable outcomes.

ART outcomes following ovarian stimulation in the luteal phase:a systematic review and meta-analysis

PURPOSE

This study aimed to evaluate the impact of luteal phase ovarian stimulation (LPS) on the outcomes of assisted reproductive technology (ART) for infertile couples and patients desiring non-urgent egg cryopreservation.

METHODS

We included all studies reported patients who received LPS and that used follicular phase ovarian stimulation (FPS) as a comparison group until January 2021. Prior meta-analysis regarding the outcomes of LPS in double stimulation and fertility preservation have already been published, so these studies were excluded. Risk of Bias in Non-randomized Studies of Interventions was used to assess the study quality. The study was registered in the International Prospective Register of Systematic Reviews database (CRD42020183946).

RESULTS

Twelve studies with a total of 4433 patients were included. The regimen employed can be categorized into two groups, but there is currently no evidence to support one over the other. After we excluded the largest study, the clinical pregnancy rate and live birth rate were similar after FPS and LPS. There were significantly more stimulation days and total gonadotropins used in the LPS group. After subgroup analysis, we found that poor responders received significantly more cumulus oocyte complexes (+0.64) in the LPS group.

CONCLUSION

Current evidence indicates that patients in the LPS group could achieve pregnancy outcomes non-inferior to those in the FPS group. Because of current debate over freeze-all policy and the limited data about live birth rate, the universal use of LPS is considered controversial. In the future, more well-designed studies are necessary to investigate the indications for LPS and its cost-effectiveness.

Ovarian follicular waves during the menstrual cycle: physiologic insights into novel approaches for ovarian stimulation

Elucidation of multiple waves of antral ovarian follicular development during the menstrual cycle has challenged traditional concepts of female reproductive physiology and foundations of assisted reproductive therapies. Approximately two-thirds of women develop two follicle waves throughout an interovulatory interval and the remainder exhibit three waves of follicle development. Major and minor waves of follicle development have been observed. Major waves are those in which a dominant follicle develops; dominant follicles either regress or ovulate. In minor waves, physiologic selection of a dominant follicle is not manifest. Knowledge of waves of antral follicular development has led to the global adoption of novel ovarian stimulation strategies in which stimulation can be initiated at various times throughout the cycle. Random-start and luteal-phase ovarian stimulation regimens have had important clinical applications for women requiring urgent oocyte or embryo cryopreservation for fertility preservation prior to chemotherapy. Ovarian stimulation twice in the same cycle, referred to as double stimulation, may be used to optimize clinical outcomes in women with a poor ovarian response to stimulation as well as in those requiring fertility preservation before chemotherapy.

Ovarian stimulation for fertility preservation in women with cancer: A systematic review and meta-analysis comparing random and conventional starts

OBJECTIVE

In female cancer patients anticipating chemotherapy or radiation, oocyte retrieval for fertility should be performed as efficiently as possible to avoid postponing cancer treatments. Our objective was to compare clinical outcomes among female cancer patients who underwent a conventional early follicular phase-start ovarian stimulation cycle and those who underwent a random-start ovarian stimulation cycle.

EVIDENCE REVIEW

A systematic review of the literature was performed in accordance with PRISMA guidelines. Medline, Embase.com, Scopus, Cochrane Library, and Clinicaltrials.gov databases were searched to identify all original research published in English through July 2020 on the topic of female cancer patients undergoing ovarian stimulation with a random or conventional start. Studies lacking a comparison group or including women who had already undergone chemotherapy at the time of ovarian stimulation were excluded. The primary author assessed all identified article titles and abstracts, and two independent reviewers assessed full-text articles and extracted data. A meta-analysis with a random-effects model was used to calculate weighted mean differences (WMDs) for outcomes of interest. The primary outcome was the number of mature (meiosis II) oocytes retrieved. Secondary outcomes included duration of stimulation, total dose of gonadotropins, total number of oocytes retrieved, fertilization rate, and number of embryos or zygotes cryopreserved.

RESULTS

A total of 446 articles were screened, and 9 full-text articles (all retrospective cohort or prospective observational) were included for review. Additionally, pooled primary retrospective data from two institutions were included. In total, data from 10 studies including 1653 women were reviewed. Five studies reported the number of embryos cryopreserved, and four reported fertilization rates. Random-start cycles were slightly longer (WMD 0.57 days, 95 % confidence interval [CI] 0.0-1.14 days) and used more total gonadotropins (WMD 248.8 international units, 95 % CI 57.24-440.40) than conventional-start cycles. However, there were no differences in number of mature oocytes retrieved (WMD 0.41 oocytes, 95 % CI -0.84-1.66), number of total oocytes retrieved (WMD 0.90 oocytes, 95 % CI -0.21-2.02), fertilization rates (WMD -0.12, 95 % CI -1.22-0.98), or number of embryos cryopreserved (WMD 0.12 embryos, 95 %CI -0.98-1.22) between random-start and conventional-start cycles. All outcomes except for the parameter "total oocytes retrieved" yielded an I² of over 50 %, indicating substantial heterogeneity between studies.

CONCLUSION(S)

Although random-start cycles may entail a longer duration of stimulation and use more total gonadotropins than conventional-start cycles, the absolute differences are small and likely do not significantly affect treatment costs. The similar numbers of mature oocytes retrieved, fertilization rates, and number of embryos cryopreserved in the two start-types suggest that they do not differ in any clinically important ways. Given that random-start cycles can be initiated quickly, they may help facilitate fertility preservation for cancer patients.

Fertility Preservation and Long-Term Monitoring of Gonadotoxicity in Girls, Adolescents and Young Adults Undergoing Cancer Treatment

Chemo- and radio-therapy can often affect reproductive organs impairing hormonal regulation, fertility, and sexual function. As cancer treatments become more effective and many patients have long term survival, concerns related to patient's quality of life and reproductive health become relevant. It is especially important for girls and young females facing cancer therapy who have not yet started family planning. Chemotherapy protocols using alkylating agents and abdominal radiotherapy, which are frequently used in the treatment of childhood and adolescent cancer, can cause gonadal injury. The most common clinical manifests are ovarian hormone insufficiency, premature ovarian insufficiency, early menopause and infertility. In this review we assess current literature and summarize current recommendations on the reproductive function of girls and young females undergoing cancer treatment and their follow-up. Fertility preservation methods are discussed, including psychological and ethical considerations and barriers. Improvement of reproductive health and quality of life of adolescents and young adults (AYA) undergoing cancer treatment is an important issue. Further research should be continued to develop efficient and accessible methods for fertility preservation in young patients. An expert panel including oncologists, radiation oncologists, endocrinologists and gynecologists should always consider fertility preservation in pediatric, adolescent and AYA cancer patients, minding patients' medical condition, cancer staging and potential risk of treatment-related gonadotoxicity.

Comparison of Oocyte and Embryo Quality Between Random Start and Controlled Ovarian Stimulation Cycles in Cancer Patients Undergoing Fertility Preservation

Conventional assisted reproductive technology (ART) cycles may delay cancer treatment and compromise survival, and also increase patients' psychological burden as a result of delayed chemotherapy. The aim of this study was to compare the success rates of random start and conventional start GnRH antagonist protocols in terms of oocyte and embryo outputs in cancer patients. Data of 111 patients with a newly diagnosed cancer who underwent ART for fertility preservation at a university-based infertility clinic between January 2010 and September 2019 were reviewed. The study group underwent random start controlled ovarian hyperstimulation (RS-COH) and the control group underwent conventional start COH (CS-COH). The main outcome measures were the number of total oocytes, MII oocytes, and embryo yield. A total of 46 patients (41.5%) underwent RS-COH and 65 (58.5%) underwent CS-COH. Baseline characteristics were similar between the groups. The most common cancer type in both groups was breast cancer (60.9% vs. 52.3%, respectively). The median duration of stimulation was significantly longer in RS-COH than in CS-COH (12 vs. 10 days; P = 0.005). The median number of MII oocytes was significantly higher in RS-COH than in CS-COH (7 vs. 5 oocytes, respectively; P = 0.020). The MII/AFC ratio was significantly higher in the RS-COH group compared to the CS-COH group (74% and 57% respectively; p = 0.02). In the linear regression analyses, RS-COH protocol did not have a significant impact on MII/AFC (standardized ß coefficient - 0.514; P = 0.289 {adjusted R² for the model = 0.779}), oocyte yield (standardized ß coefficient - 0.070; P = 0.829 {adjusted R² for the model = 0.840}), and MII rate (standardized ß coefficient - 0.504; P = 0.596 {adjusted R² for the model = 0.271}). In conclusion, RS-COH protocol is as effective as CS-COH protocols for fertility preservation in cancer patients.

Nationwide survey of Japanese breast oncology and reproductive endocrinology departments about the impact of breast cancer treatment on fertility

The purpose of this study is to assess the impact of breast cancer treatment on the reproductive potential. We conducted a nationwide survey of breast oncology and reproductive endocrinology and infertility (REI) departments using a questionnaire designed to assess the impact of breast cancer treatment on fertility. We received responses from 312 breast oncology departments (response rate, 31.9%) and 541 REI departments (response rate, 50.9%). The most common method of achieving pregnancy reported by breast oncology departments was natural insemination (69.6%), followed by assisted reproductive technology ( 15.6%) and intrauterine insemination (IUI; 14.8%). The most common method of achieving pregnancy reported by REI departments was conventional in vitro fertilization and/or intracytoplasmic sperm injection (51.0%), followed by natural insemination with or without ovulation induction (40.0%) and IUI (8.0%). The overall pregnancy rate for patients who underwent treatment for infertility at REI departments after breast cancer treatment was 39.0%. Vast patients who experienced breast cancer treatments conceived mainly by natural insemination based on the data from breast oncology departments. On the other hand, 61.0% of the patients who visited REI departments presumably due to infertility by natural insemination did not conceive even by infertility treatments with exclusive knowledge in REI departments.

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.

Fertility preservation in borderline ovarian tumor patients and survivors

Borderline ovarian tumors (BOTs) represent around 15% of all epithelial ovarian cancer. Around one third of those patients is under 40 and has not completed childbearing when the tumor is diagnosed. Cancer survivors are more and more concerned about their future fertility since a large proportion of those with BOTs are young. Whatever the tumor stage, information regarding future fertility after treatment and fertility preservation (FP) options must be delivered to all patients before treatment. A multidisciplinary team will discuss and propose personalized treatment and FP strategies. Nowadays, the FP options offered to patients with BOT are the followings: i) minimal invasive conservative surgery, ii) oocyte cryopreservation after controlled ovarian stimulation (COS) or in vitro maturation (IVM) and iii) ovarian tissue cryopreservation. Generally, the most common strategy to preserve future fertility is represented by minimal invasive conservative surgery. However, with the remarkable success and evolution of assisted reproductive technologies (ART) - notably progress and efficiency in COS and oocyte vitrification - have led to offer another potential approach for FP consisting in oocyte cryopreservation. Several COS protocols, such as random start or dual stimulation associating tamoxifen or aromatase inhibitors with gonadotropins provide similar results when compared to standard protocols while providing safety by minimizing the risk of high estrogen exposure. When COS is contraindicated, oocyte cryopreservation can still be possible throw IVM. Even though, oocyte competence after IVM is lower than that obtained after COS. A less used approach is cryopreservation of ovarian tissue, consisting in freezing ovarian cortex fragments for a future thawing and graft. Some concerns and limitations regard the ovarian cortex graft and the risk of reintroducing malignant cells once performed. Nonetheless, the latter it is the only option in prepubertal patients.

The presence of dominant follicles and corpora lutea does not perturb response to controlled ovarian stimulation in random start protocols

The advent of random start protocols to shorten the time needed to store oocytes in women with malignancies has represented an important improvement in the field of fertility preservation. However, Randomized Controlled Trials are difficult to implement in this area and available evidence that supports this approach remains modest. To shed more light on this issue, we compared the follicular development between the ovary carrying the dominant follicle or the corpus luteum and the contralateral resting ovary in 90 women who underwent random start controlled ovarian stimulation (COS). In fact, ovarian response did not differ between the two ovaries. Subgroup analyses according to the phase of the cycle at the initiation of COS, the type of malignancy, the use of letrozole and the magnitude of the ovarian response did not allow to identify any condition showing a difference in the follicular response between the active and the resting ovaries. In conclusion, follicular growth does not seem to be perturbed by the presence of a dominant follicle or a corpus luteum.

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.

Fertility preservation in BRCA mutation carriers-efficacy and safety issues: a review

BRCA mutation carriers face various situations that influence their fertility potential. There is still a lack of guideline or expert consensus on Fertility Preservation (FP) in BRCA mutation carriers and the necessity and safety of FP in BRCA mutation carriers is still in dispute. This review aims to focus on the population of BRCA mutation carriers by analyzing the existing FP strategies, comprehensively comparing the pros and cons of each strategy and its applicability.FP is a suggestion for BRCA mutation carriers with birth planning. Different FP strategies have different characteristics. Considering the particularity of BRCA mutation carriers, multiple factors need to be carefully considered. This review focuses on the applicability of each FP method for carriers under various circumstances. Available FP strategies including oocyte cryopreservation, ovarian tissue cryopreservation, preimplantation genetic diagnosis, and egg/embryo donation are analyzed by comparing existing methods comprehensively. In the attempt to provide an up-to-date decision-making guidance. Conditions taking into consideration were the carrier's age, the risk of breast and ovarian metastasis, plans for oncotherapy, FP outcome, time available for FP intervention and accessibility.Overall, FP is necessary and safe for BRCA mutation carriers. Among all available FP methods, oocyte cryopreservation is the most reliable procedure; ovarian tissue cryopreservation is the only way for preserving both fertility and endocrine function, recommended for pre-pubertal carriers and when time is limited for oocyte stimulation. A clear framework provides frontline clinical practitioners a new thought and eventually benefit thousands of BRCA mutation carriers.