Minimal Infiltrative Disease Identification in Cryopreserved Ovarian Tissue of Girls with Cancer for Future Use: A Systematic Review

Heterotopic ovarian transplantation instead hormonal replacement therapy after radical hysterectomy for cervical cancer: case report and review of literature

PURPOSE

Only a few case reports have described heterotopic ovarian tissue transplantation (OTT) with the only objective of restoring ovarian function.

METHODS

Case report and review of the literature for reporting cases of heterotopic OTT with the only aim of restoring ovarian endocrine function. In a cancer survivor woman with a history of hysterectomy and bilateral oophorectomy for cervical cancer and because she poorly tolerated hormone replacement therapy (HRT), we performed a heterotopic OTT in a pelvic subcutaneous "pocket" after an OT cryostorage of 17 years.

RESULTS

A cyclic ovarian endocrine function started 3 months after OTT with an immediate patient self-described improvement of her quality of life. A second OTT was performed 19 months after, due to hot flushes recurrence and FSH increase. Despite a cyclic endocrine function, progesterone levels have always been low, resulting in a relative hyperoestrogenism state.

CONCLUSION

In the future, the indications of heterotopic OTT could be spread in alternative to HRT. However, our data suggest that the heterotopic graft environment is less favorable to corpus luteum development, and further studies are needed to assay the best site of heterotopic graft, the optimal number of ovarian cortex fragments to graft, and the potential risk of relapse in case of malignant residual disease.

Ovarian Insufficiency and Fertility Preservation During and After Childhood Cancer Treatment

Premature ovarian insufficiency (POI) is one of many potential long-term consequences of childhood cancer treatment in females. Causes of POI in this patient population can include chemotherapy, especially alkylating agents, and radiation therapy. Rarely, ovarian tumors lead to ovarian dysfunction. POI can manifest as delayed pubertal development, irregular menses or amenorrhea, and infertility. This diagnosis often negatively impacts emotional health due to the implications of impaired ovarian function after already enduring treatment for a primary malignancy. The emerging adult may be challenged by the impact on energy level, quality of life, and fertility potential. POI can also lead to low bone density and compromised skeletal strength. This review discusses the health consequences of POI in childhood cancer survivors (CCS). We also explore the role of fertility preservation for CCS, including ovarian tissue cryopreservation and other available options. Lastly, knowledge gaps are identified that will drive a future research agenda.

A 20-year overview of fertility preservation in boys: new insights gained through a comprehensive international survey

STUDY QUESTION

Twenty years after the inception of the first fertility preservation programme for pre-pubertal boys, what are the current international practices with regard to cryopreservation of immature testicular tissue?

SUMMARY ANSWER

Worldwide, testicular tissue has been cryopreserved from over 3000 boys under the age of 18 years for a variety of malignant and non-malignant indications; there is variability in practices related to eligibility, clinical assessment, storage, and funding.

WHAT IS KNOWN ALREADY

For male patients receiving gonadotoxic treatment prior to puberty, testicular tissue cryopreservation may provide a method of fertility preservation. While this technique remains experimental, an increasing number of centres worldwide are cryopreserving immature testicular tissue and are approaching clinical application of methods to use this stored tissue to restore fertility. As such, standards for quality assurance and clinical care in preserving immature testicular tissue should be established.

STUDY DESIGN SIZE DURATION

A detailed survey was sent to 17 centres within the recently established ORCHID-NET consortium, which offer testicular tissue cryopreservation to patients under the age of 18 years. The study encompassed 60 questions and remained open from 1 July to 1 November 2022.

PARTICIPANTS/MATERIALS SETTING METHODS

Of the 17 invited centres, 16 completed the survey, with representation from Europe, Australia, and the USA. Collectively, these centres have cryopreserved testicular tissue from patients under the age of 18 years. Data are presented using descriptive analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Since the establishment of the first formal fertility preservation programme for pre-pubertal males in 2002, these 16 centres have cryopreserved tissue from 3118 patients under the age of 18 years, with both malignant (60.4%) and non-malignant (39.6%) diagnoses. All centres perform unilateral biopsies, while 6/16 sometimes perform bilateral biopsies. When cryopreserving tissue, 9/16 centres preserve fragments sized ≤5 mm3 with the remainder preserving fragments sized 6-20 mm3. Dimethylsulphoxide is commonly used as a cryoprotectant, with medium supplements varying across centres. There are variations in funding source, storage duration, and follow-up practice. Research, with consent, is conducted on stored tissue in 13/16 centres.

LIMITATIONS REASONS FOR CAUTION

While this is a multi-national study, it will not encompass every centre worldwide that is cryopreserving testicular tissue from males under 18 years of age. As such, it is likely that the actual number of patients is even higher than we report. Whilst the study is likely to reflect global practice overall, it will not provide a complete picture of practices in every centre.

WIDER IMPLICATIONS OF THE FINDINGS

Given the research advances, it is reasonable to suggest that cryopreserved immature testicular tissue will in the future be used clinically to restore fertility. The growing number of patients undergoing this procedure necessitates collaboration between centres to better harmonize clinical and research protocols evaluating tissue function and clinical outcomes in these patients.

STUDY FUNDING/COMPETING INTERESTS

K.D. is supported by a CRUK grant (C157/A25193). R.T.M. is supported by an UK Research and Innovation (UKRI) Future Leaders Fellowship (MR/S017151/1). The MRC Centre for Reproductive Health at the University of Edinburgh is supported by MRC (MR/N022556/1). C.L.M. is funded by Kika86 and ZonMW TAS 116003002. A.M.M.v.P. is supported by ZonMW TAS 116003002. E.G. was supported by the Research Program of the Research Foundation-Flanders (G.0109.18N), Kom op tegen Kanker, the Strategic Research Program (VUB_SRP89), and the Scientific Fund Willy Gepts. J.-B.S. is supported by the Swedish Childhood Cancer Foundation (TJ2020-0026). The work of NORDFERTIL is supported by the Swedish Childhood Cancer Foundation (PR2019-0123; PR2022-0115), the Swedish Research Council (2018-03094; 2021-02107), and the Birgitta and Carl-Axel Rydbeck's Research Grant for Paediatric Research (2020-00348; 2021-00073; 2022-00317; 2023-00353). C.E is supported by the Health Department of the Basque Government (Grants 2019111068 and 2022111067) and Inocente Inocente Foundation (FII22/001). M.P.R. is funded by a Medical Research Council Centre for Reproductive Health Grant No: MR/N022556/1. A.F. and N.R. received support from a French national research grant PHRC No. 2008/071/HP obtained by the French Institute of Cancer and the French Healthcare Organization. K.E.O. is funded by the University of Pittsburgh Medical Center and the US National Institutes of Health HD100197. V.B-L is supported by the French National Institute of Cancer (Grant Seq21-026). Y.J. is supported by the Royal Children's Hospital Foundation and a Medical Research Future Fund MRFAR000308. E.G., N.N., S.S., C.L.M., A.M.M.v.P., C.E., R.T.M., K.D., M.P.R. are members of COST Action CA20119 (ANDRONET) supported by COST (European Cooperation in Science and Technology). The Danish Child Cancer Foundation is also thanked for financial support (C.Y.A.). The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Influence of ovarian stromal cells on human ovarian follicle growth in a 3D environment

STUDY QUESTION

Do ovarian stromal cells (OSCs) influence the viability and growth of human preantral follicles in vitro?

SUMMARY ANSWER

A feeder layer of OSCs promotes the growth and transition of low developmental stage follicles to the primary/secondary stage while maintaining a high proportion of viable follicles.

WHAT IS KNOWN ALREADY

In the ovary, follicles rely on the support of ovarian cells, which secrete essential factors for their survival and development. This phenomenon has also been demonstrated in vitro through the 3D culture of isolated mouse primary and secondary follicles on a feeder layer of OSCs. This co-culture notably enhances follicle survival and growth.

STUDY DESIGN SIZE DURATION

Pre-antral follicles were isolated from human frozen-thawed ovarian tissue biopsies and then encapsulated in 1% alginate scaffolds. These embedded preantral follicles were either placed directly on the OSCs feeder layer or at the bottom of a culture dish for a 7-day in vitro culture (control). The study compared follicle viability, growth, and hormone production between the different groups.

PARTICIPANTS/MATERIALS SETTING METHODS

Primordial/intermediate and primary follicles were isolated from frozen-thawed ovarian tissue of cancer patients (n = 6). OSCs were then isolated from ovarian tissue of post-menopausal women and cultured as a feeder layer. Follicle diameter was measured on Days 0 and 7 using an inverted microscope to assess their development based on the increase in diameter. Viability was evaluated by staining a subset of follicles (n = 87) with calcein AM and ethidium homodimer-I, followed by classification into healthy/minimally damaged and damaged/dead follicles using confocal fluorescence microscopy. Additionally, estradiol levels were measured using ELISA.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 382 human preantral follicles (370 primordial/intermediate and 12 primary) with a mean diameter of 40.8 ± 9.9 µm (mean ± SD) were isolated, embedded in 1% alginate hydrogel, and placed either on a monolayer of OSCs or directly on the plastic. By Day 7, the preantral follicles showed a significant size increase under both culture conditions (P < 0.0001 for D0 vs D7). The mean diameter of follicles (quiescent and growing) cultured on the feeder layer was 80.6 ± 11.0 μm compared to 67.3 ± 7.2 μm without it (P = 0.07). During the 7-day in vitro culture, the viability of the follicles significantly decreased only in the group without an OSCs monolayer compared to the D0 viability (P < 0.05). Additionally, more follicles transitioned to a higher developmental stage in the presence of OSCs (D0 primordial/intermediate: 184, primary: 7 vs D7 primordial/intermediate: 51, primary/secondary: 93) compared to those cultured without OSCs (D0 primordial/intermediate: 186, primary: 5 vs D7 primordial/intermediate: 84, primary/secondary: 65; P < 0.001). Specifically, 66 and 44 follicles reached the secondary stage (75< x <200 μm) in the presence and absence of OSCs, respectively. Moreover, the estradiol level was significantly higher (P = 0.006) in the alginate beads containing primordial and growing follicles cultured on the OSCs (54.1 ± 14.2 pg/ml) compared to those cultured without OSCs (29.9 ± 4.0 pg/ml).

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

This study was conducted using a short-term culture, and none of the primordial/intermediate/primary follicles reached the antral stage. Further in vitro studies are required to investigate follicular developmental capacity, physiology, and steroidogenesis in alginate scaffolds with human OSCs.

WIDER IMPLICATIONS OF THE FINDINGS

Activating and growing human primordial/intermediate follicles to a secondary stage in in vitro short-term culture has posed a longstanding challenge. However, co-culturing with human OSCs has shown the potential to overcome this limitation.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (FNRS-PDR Convention grant number T.0004.20 awarded to C.A.A., PhD scholarship awarded to H.V.), Fondation Louvain (awarded to C.A.A.; PhD scholarship awarded to S.M., as part of a legacy from Mr Frans Heyes, and PhD scholarship awarded to A.D. as part of a legacy from Mrs Ilse Schirmer), Foundation Against Cancer (grant 2018-042 awarded to A.C.), and the European Community Structural Funds and Lithuanian Research Council (Agreement registration No. D-19-0874). The authors have no conflicts of interest to declare.