Testicular niche repair after gonadotoxic treatments: Current knowledge and future directions.

The testicular niche, which includes the germ cells, somatic cells, and extracellular matrix, plays a crucial role in maintaining the proper functions of the testis. Gonadotoxic treatments, such as chemotherapy and radiation therapy, have significantly improved the survival rates of cancer patients but have also been shown to have adverse effects on the testicular microenvironment. Therefore, repairing the testicular niche after gonadotoxic treatments is essential to restore its function. In recent years, several approaches, such as stem cell transplantation, gene therapy, growth factor therapy, and pharmacological interventions have been proposed as potential therapeutic strategies to repair the testicular niche. This comprehensive review aims to provide an overview of the current understanding of testis damage and repair mechanisms. We will cover a range of topics, including the mechanism of gonadotoxic action, repair mechanisms, and treatment approaches. Overall, this review highlights the importance of repairing the testicular niche after gonadotoxic treatments and identifies potential avenues for future research to improve the outcomes for cancer survivors.

Molecular Mechanisms Determining Mammalian Oocyte Quality with the Treatment of Cancer Therapy.

Cancer is a global public health issue and remains one of the leading causes of death in the United States (Siegel et al. CA Cancer J Clin. 72:7-33, 2022). It is estimated in the US in 2022, about 935,000 new cases of cancer will be diagnosed in women, and the probability of developing invasive cancer is 5.8% for females younger than 50 years old (Siegel et al. CA Cancer J Clin. 72:7-33, 2022). However, advances in screening programs, diagnostic methods, and therapeutic options have greatly increased the five-year survival rate in reproductive-age women with a variety of cancers. Given the clinical consequences of gonadotoxic cancer therapies, young, female cancer survivors may face compromised fertility, premature ovarian insufficiency, early-onset menopause, and endocrine dysregulation (Bedoschi et al. Future Oncol. 12:2333-44, 2016). Gonadotoxic side effects may include decreased oocyte quality within surviving follicles, loss of ovarian follicles, and impaired ovarian function. In reproductive-age women, oocyte quality is an important element for successful clinical pregnancies and healthy offspring as poor-quality oocytes may be a cause of infertility (McClam et al. Biol Reprod. 106:328-37, 2022; Marteil et al. Reprod Biol. 9:203-24, 2009; Krisher. J Anim Sci. 82: E14-E23, 2004). Thus, it is critical to determine the quantity and quality of surviving follicles in the ovary after cancer treatment and to assess oocyte quality within those surviving follicles as these are markers for determining the capacity for ovarian function restoration and future fertility, especially for young cancer survivors (Xu et al. Nat Med. 17:1562-3, 2011). The long-term effects of cancer therapeutics on oocyte quality are influenced by factors including, but not limited to, individual patient characteristics (e.g. age, health history, comorbidities, etc.), disease type, or treatment regimen (Marci et al. Reprod Biol Endocrinol. 16:1-112, 2018). These effects may translate clinically into an impaired production of viable oocytes and compromised fertility (Garutti et al. ESMO Open. 6:100276, 2021).

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.

Cryopreservation of Human Spermatozoa: Functional, Molecular and Clinical Aspects.

Cryopreservation is an expanding strategy to allow not only fertility preservation for individuals who need such procedures because of gonadotoxic treatments, active duty in dangerous occupations or social reasons and gamete donation for couples where conception is denied, but also for animal breeding and preservation of endangered animal species. Despite the improvement in semen cryopreservation techniques and the worldwide expansion of semen banks, damage to spermatozoa and the consequent impairment of its functions still remain unsolved problems, conditioning the choice of the technique in assisted reproduction procedures. Although many studies have attempted to find solutions to limit sperm damage following cryopreservation and identify possible markers of damage susceptibility, active research in this field is still required in order to optimize the process. Here, we review the available evidence regarding structural, molecular and functional damage occurring in cryopreserved human spermatozoa and the possible strategies to prevent it and optimize the procedures. Finally, we review the results on assisted reproduction technique (ARTs) outcomes following the use of cryopreserved spermatozoa.

Preservation of male fertility in patients undergoing pelvic irradiation.

As the number of cancer survivors increases, so does the demand for preserving male fertility after radiation. It is important for healthcare providers to understand the pathophysiology of radiation-induced testicular injury, the techniques of fertility preservation both before and during radiation, and their role in counseling patients on the risks to their fertility and the means of mitigating these risks. Impaired spermatogenesis is a known testicular toxicity of radiation in both the acute and the late settings, as rapidly dividing spermatogonial germ cells are exquisitely sensitive to irradiation. The threshold for spermatogonial injury and subsequent impairment in spermatogenesis is ~ 0.1 Gy and the severity of gonadal injury is highly dose-dependent. Total doses < 4 Gy may allow for recovery of spermatogenesis and fertility potential, but with larger doses, recovery may be protracted or impossible. All patients undergoing gonadotoxic radiation therapy should be counseled on the possibility of future infertility, offered the opportunity for semen cryopreservation, and offered referral to a fertility specialist. In addition to this, every effort should be made to shield the testes (if not expected to contain tumor) during therapy.

Sexual function in male cancer survivors is not correlated to sperm quality.

PURPOSE: Both infertility and erectile dysfunction (ED) are known long-term consequences of cancer treatment in young male cancer survivors. In the present study, we aimed to assess whether sperm quality and sexual function in male cancer survivors are associated. METHODS: In this prospective study, n = 244 patients male cancer survivors who underwent sperm analysis and cryopreservation between 2008 and 2018 prior to the initiation of gonadotoxic treatment were invited. In total n = 50 had a follow-up sperm analysis and completed two questionnaires, the Aging Males' Symptom Scale (AMS) and the International Index of Erectile Function (IIEF-EF). Differences between the individual parameters were analyzed using the Wilcoxon or Mann Whitney test. RESULTS: Azoospermia was present in n = 16/50 (32.0%) patients at time of follow-up. ED occurred in n = 9/43 (20.9%) patients and was observed more frequently in patients with oligo- or azoospermia than in those with normospermia, even though this association was not statistically significant. Sperm parameters (total sperm count, sperm concentration, progressive motility) did not differ between time of cryopreservation and time of follow-up. Mean total, somatic, psychological, and sexual AMS score was 23.6, 9.9, 6.6, and 6.8, respectively. Mean total IIEF-EF score was 27.3, indicating mainly mild ED. CONCLUSIONS: More than one-third of cancer patients suffered from azoospermia, and ED was primarily present in this subgroup. We recommend implementing the screening of sexual dysfunction in the annual sperm testing that should be offered to all men after gonadotoxic treatment. Our study highlights the importance of counseling young cancer patients on both aspects-future infertility and sexual function-prior to treatment and at follow-up visits.

Endometriosis in women undergoing ovarian tissue transplantation due to premature menopause after gonadotoxic treatment or spontaneous premature ovarian failure.

INTRODUCTION: Cryopreservation of ovarian tissue with subsequent transplantation is an efficient option for restoring fertility in women at risk of premature ovarian failure. The association between infertility and endometriosis is well recognized. Although endometriosis usually ends with the onset of natural or iatrogen menopause due to declining estrogen levels, endometriosis can in rare cases occur after menopause. This study aims to investigate women with premature menopause who were diagnosed with endometriosis during laparoscopy for ovarian tissue transplantation, and to address the questions of how endometriotic lesions after cytotoxic treatment and premature menopause might be explained, whether endometriosis affects pregnancy rates, and whether there is an association between endometriosis and the original cancer. MATERIAL AND METHODS: Seventeen patients who had undergone ovarian tissue transplantation to restore their fertility and who were diagnosed with endometriosis during transplantation were included in this retrospective study. The endometriosis foci were completely removed and ovarian tissue was transplanted into the pelvic peritoneum. Preexisting conditions, use of hormonal preparations, endometriosis stage pain assessment, as well as pregnancy and live birth rate were evaluated. RESULTS: The mean age of the patients was 29.5 ± 6.3 years (range 14-39) at the time of ovarian tissue harvest and 34.6 ± 4.3 years (range 28-40) at transplantation. Prior to transplantation, four patients had taken hormone replacement therapy, four women oral contraceptives and two patients' tamoxifen. Twelve women had stage I endometriosis and five stage II endometrioses according to the rASRM classification. Four patients reported dysmenorrhea. None of the women complained of general pelvic pain or dyspareunia. The pregnancy rate in the study population was 41.2%, with a live birth rate of 35.3%. The pregnancies occurred in three cases after spontaneous conception, in four women after a natural cycle IVF/ICSI. CONCLUSIONS: This study highlights the under-researched association between endometriosis in women entering premature or early menopause either after gonadotoxic treatment or due to primary ovarian insufficiency. As more and more patients seek to have their cryopreserved ovarian tissue transplanted to fulfill their desire to have children, specialists will inevitably encounter women with this condition.

Failed ovarian cortex transplant but successful ovulation induction in a cancer survivor with premature ovarian failure: A paradox.

Better diagnostic and treatment modalities for malignancies occurring in childhood and young age have increased the overall survival of the affected young girls and boys, but this has come at a cost of developing premature ovarian failure in girls and azoospermia in boys because of the gonadotoxicity of chemotherapy and radiotherapy. Thus, young girls and women of reproductive age who are at risk of ovarian failure due to cancer treatment must be mandatorily offered fertility preservation in any form such as cryopreservation of mature metaphase II oocytes after ovarian stimulation with gonadotropins and oocyte recovery and cryopreservation of embryos if the young female has a partner. However, these modalities may require the postponement of chemotherapy. Thus, in such instances, cryopreservation of ovarian tissue remains the only option. Herein, we report a case of a nulligravid young female patient who had stage IV Hodgkin's lymphoma and had to be taken up for immediate fertility preservation owing to the advanced stage of the disease. Therefore, cryopreservation of ovarian tissue was performed. The uniqueness of the case is that after remission of the disease was achieved with chemotherapy, transplantation of the ovarian tissue was carried out which was not successful, but the desire for motherhood prompted to carry out an ovulation induction in the remnant native ovary with a severely compromised ovarian reserve, and she conceived.

Predictive factors for fertility preservation in pediatric and adolescent girls with planned gonadotoxic treatment.

PURPOSE: To characterize female pediatric and adolescent patients seen for fertility preservation consultation at an academic medical center and to describe the association between demographic or clinical factors and the use of fertility preservation treatment (FPT). METHODS: This is a retrospective chart analysis of female pediatric and adolescent patients seen for fertility preservation consultation at an academic fertility center over a 14-year period from 2005 to 2019. RESULTS: One hundred six females aged 3-21 years were seen for fertility preservation consultation with a mean age of 16.6 years. Diagnoses included hematologic malignancies (41.5%), gynecologic malignancies (9.4%), other malignancies (31.1%), non-malignant hematologic disease (14.2%), and non-malignant conditions (3.8%). Overall, 64.2% of subjects pursued fertility preservation, including oocyte cryopreservation (35.8%) and ovarian tissue cryopreservation (23.6%). Overall, age, minority race, diagnosis, time since diagnosis, and median household income were not significantly associated with odds of completing an FPT procedure. Among all patients, those who underwent gonadotoxic therapy prior to consultation had a lower odds of receiving FPT (OR= 0.24, 95% CI 0.10-0.55). Among patients without chemotherapy exposure, no factors were associated with FPT. CONCLUSIONS: Among pediatric and adolescent patients at an academic center undergoing a fertility preservation consultation, there were no socioeconomic or clinical barriers to FPT use in those who had not yet undergone gonadotoxic therapy. The only factor that was negatively associated with odds of pursuing FPT was prior chemotherapy exposure.

Consult and procedure incidence outcomes following establishment of a fertility preservation program for children with cancer.

PURPOSE: Fertility is a quality of life outcome adversely affected by cancer therapy. Many childhood cancer patients, however, are not offered options to preserve their fertility. Providers acknowledge difficulty discussing impaired fertility to patients due to lack of knowledge of available options. Our objective was to review the impact of a pediatric multidisciplinary fertility preservation program on providers' fertility preservation counseling and discussion of options. METHODS: A retrospective medical chart review was conducted for pediatric cancer patients prior to and following program establishment. Fertility preservation discussions, consults, and incidence were noted. Following filtering and stratification, 198 and 237 patients were seen prior to and following program establishment, respectively. RESULTS: Following program establishment, provider-patient discussions of impaired fertility (p = 0.007), fertility preservation consults (p = 0.01), and incidence of fertility preservation procedures (p < 0.001) increased among patients. Furthermore, the number of patients who received fertility preservation consults after receiving gonadotoxic treatment decreased (p < 0.001). This trend was particularly noted in pre-pubertal and female patients, for whom fertility preservation options are limited without an established program. CONCLUSION: The establishment of a formal program greatly improved access to fertility preservation consults and procedures in children with cancer.

Cryopreservation of sperm before gonadotoxic treatment at the University Hospital Brno in the years 1995-2020

OBJECTIVE: Sperm cryopreservation before gonadotoxic treatment is the basic and mos teffective method of preserving reproduction, which can be used during adolescence. The communication summarizes 26 years of experience in the operation of an oncological sperm bank, analyzes spermiograms of oncological patients, assesses the relationship between sperm pathology and diagnosis, and determines the number of deaths and the use of frozen sperm. METHODS: During the existence of CAR 01 (assisted reproduction center), more than 50,000 spermiograms were performed. From January 1995 to December 2020, a total of 24,729 men were examined within the sperm bank, of which 1,448 (5.9%) had an oncological diagnosis. The spermiograms were evaluated according to current WHO (World Health Organization) manuals. Cryopreservation of sperm has undergone a major development. The rules for the storage of frozen cells have been laid down by Act No. 296/2008 Coll. since 2008. In 2019, the methodology "Cryopreservation of reproductive cells and tissues in patients before cancer treatment" was updated. In all cases, the standard thawing technique was used. The sperms were processed by the swim-up method. As part of the treatment with assisted reproduction methods, oocytes were fertilized by the ICSI (intracytoplasmatic sperm injection) micromanipulation technique. RESULTS: Out of 1,448 examined spermiograms in men with oncological diagnoses, testicular cancer was present in 43.7% of patients and malignant diseases of lymphatic and hematopoietic tissue were found in 24.1%, of which 70,1% included Hodgkin's lymphomas and 29,9% were non-Hodgkin's lymphomas. Leukemia was found in 7.9%, bone and cartilage cancers in 6.8%. The age of the clients of the whole group ranged from 13 to 64 years (27.2 ± 6.8 years). A total of 38.3% of men had normozoospermia, 54.2% of spermiograms showed pathological findings in 1 to 3 evaluated parameters and 7.5% of patients had azoospermia. Severe asthenozoospermia (mobility ≤ 10%) was detected in 57.2% of men and severe oligozoospermia (concentration ≤ 1 × 106 mm3) in 22.3% of patients. The lowest values of the spermiogram were found in men with testicular cancer; the best values were seen in CNS (central nervous system) cancers. The cryopreservation of sperm was performed in 1,340 cases (92.5%). So far, a total of 160 men (11.9%) have used frozen sperm, of which 6.2% in our center. In these 83 cases, the ICSI technique was always used, 38 clinical pregnancies (45.8%) and 32 births were achieved. We have registered 424 completed storages of semen (31.6%), of which 148 (11.0% of all oncology patients) were made due to death and the others at patients' request. Using the sperm of the dead is a specific issue. CONCLUSION: In cancer patients, sperm pathologies occur in high percentage. The lowest spermiogram values were found in men with testicular cancer. It is necessary to take into account long-term storage and fertilization by micromanipulation methods. The number of men who die is significantly higher than the number of those who use sperm to treat infertility. Cryopreservation of sperm should be offered to each patient prior to the therapy leading to the destruction of spermatogenesis.

A Warning Call for Fertility Preservation Methods for Women Undergoing Gonadotoxic Cancer Treatment.

Malignant hematological conditions have recognized an increased incidence and require aggressive treatments. Targeted chemotherapy, accompanied or not by radiotherapy, raises the chance of defeating the disease, yet cancer protocols often associate long-term gonadal consequences, for instance, diminished or damaged ovarian reserve. The negative effect is directly proportional to the types, doses, time of administration of chemotherapy, and irradiation. Additionally, follicle damage depends on characteristics of the disease and patient, such as age, concomitant diseases, previous gynecological conditions, and ovarian reserve. Patients should be adequately informed when proceeding to gonadotoxic therapies; hence, fertility preservation should be eventually regarded as a first-intention procedure. This procedure is most beneficial when performed before the onset of cancer treatment, with the recommendation for embryos or oocytes' cryopreservation. If not feasible or acceptable, several options can be available during or after the cancer treatment. Although not approved by medical practice, promising results after in vitro studies increase the chances of future patients to protect their fertility. This review aims to emphasize the mechanism of action and impact of chemotherapy, especially the one proven to be gonadotoxic, upon ovarian reserve and future fertility. Reduced fertility or infertility, as long-term consequences of chemotherapy and, particularly, following bone marrow transplantation, is often associated with a negative impact of recovery, social and personal life, as well as highly decreased quality of life.

Key recommendations for high-quality female oncofertility care based on international clinical practice guidelines.

RESEARCH QUESTION: Which guideline-based key recommendations can be selected for high-quality female oncofertility care? DESIGN: The Delphi method was used to select a set of key recommendations for female oncofertility care. First, recommendations from (inter)national clinical practice guidelines were selected in four domains: risk communication, referral, counselling and decision-making. Thereafter, they were scored, per domain, on their importance for high-quality oncofertility care by a multidisciplinary, oncofertility expert panel, consisting of patients, referrers and counsellors, in two Delphi rounds. Finally, the selected key recommendations were presented for approval in a third round. Differences in perspectives between subgroups of the expert panel were analysed. RESULTS: A panel of 86 experts was asked to select key recommendations for high-quality oncofertility care. Eleven key recommendations were selected. Key recommendations in the domains risk communication and referral focused on information provision and offering referral to a reproductive specialist to female cancer patients. With the counselling domain, key recommendations focused on all aspects of counselling, including different methods, safety, pros and cons. In the decision-making domain, key recommendations focused on shared decision-making and supporting the decision with written information. The final set of key recommendations was approved by 91% of the experts. Differences in perspectives were found between subgroups. Patients found recommendations on decision-making and information provision more important. CONCLUSION: A set of 11 key recommendations for high-quality female oncofertility care was selected by a multidisciplinary expert panel. The involvement of the perspectives of patients, referrers and counsellors led to this valid, acceptable and credible set of key recommendations.

Overnight ovarian tissue transportation for centralized cryobanking: a feasible option.

RESEARCH QUESTION: Is overnight transportation of ovarian tissue before cryopreservation in a centralized cryobank from the FertiPROTEKT network feasible? DESIGN: Data from 1810 women with cryopreserved ovarian tissue after overnight transportation from December 2000 to December 2017 were analysed with a focus on transportation, tissue activity parameters and pregnancy, and delivery rates after transplantation. RESULTS: A total of 92.4% of tissue samples arrived at ideal temperatures of 2-8°C, 0.4% were transported at temperatures lower than ideal and 6.4% were transported at temperatures that were too high, generally due to mishandling of the inlayed cool packs of the transportation boxes. In 62 women, 78 tissue transplantations were carried out. A subgroup of 30 women who underwent a single orthotopic transplantation with fulfilled criteria of a complete follow-up after transplantation until the end of study, a premature ovarian insufficiency after gonadotoxic therapy as well as the absence of pelvic radiation, was further analysed. In this group, transplantations into a peritoneal pocket accounted for 90%. Transplants were still active at 1 year and above after transplantation in 93.3%. Pregnancy and delivery rates were 46.7% and 43.3%, respectively, with one ongoing pregnancy at the end of the study. CONCLUSIONS: Overnight transportation for central cryobanking is a feasible concept that results in high reproducible success rates through standardized professional tissue freezing and storage.

Iatrogenic and non-iatrogenic causes of female fertility loss that may indicate fertility preservation.

Due to advances in fertility preservation options and improvements in life expectancy, there is growing need for fertility preservation counseling for women at risk for premature ovarian insufficiency. The aim of this review is to provide an overview of various causes of female fertility loss and to raise awareness for counseling women about their options for fertility preservation. Furthermore, for counseling of women not only at the time of gonadotoxic treatment but also post-treatment and also of women with other benign causes of increased risk for impaired fertility or premature ovarian insufficiency.

Ovarian tissue cryopreservation for fertility preservation in 418 girls and adolescents up to 15 years of age facing highly gonadotoxic treatment. Twenty years of experience at a single center.

INTRODUCTION: The preservation of fertility is an integral part of care of children requiring gonadotoxic treatments for cancer or non-malignant diseases. In France, the cryopreservation of ovarian tissue has been considered and has been offered as a clinical treatment since its inception. The aim of this study is to review 20 years of activity in fertility preservation by ovarian tissue cryopreservation (OTC) for children and the feasibility of oocyte isolation and cryopreservation from the ovarian tissue at a single center. MATERIAL AND METHODS: Retrospective study including patients aged 15 years or younger who underwent OTC, combined for some with oocyte cryopreservation of isolated oocytes, before a highly gonadotoxic treatment for malignant or non-malignant disease was initiated. We describe the evolution of activities in our program for fertility preservation and patient characteristics at the time of OTC and follow up. RESULTS: From April 1998 to December 2018, 418 girls and adolescents younger than 15 years of age underwent OTC, representing 40.5% of all females who have had ovarian tissue cryopreserved at our center. In all, 313 patients had malignant diseases and 105 had benign conditions. Between November 2009 and July 2013, oocytes were isolated and also cryopreserved in 50 cases. The mean age of patients was 6.9 years (range 0.3-15). The most frequent diagnoses in this cohort included neuroblastoma, acute leukemia and hemoglobinopathies; neuroblastoma being the most common diagnosis in very young patients. During follow up, three patients requested the use of their cryopreserved ovarian tissue. All had undergone ovarian tissue transplantation, one for puberty induction and the two others for restoring fertility. So far, no pregnancies have been achieved. Eighty-four patients who had OTC died. CONCLUSIONS: Ovarian tissue cryopreservation is the only available technique for preserving fertility of girls. To our knowledge this is the largest series of girls and adolescents younger than 15 years so far reported on procedures of OTC before highly gonadotoxic treatment in a single center.

Deliveries following fertility preservation by ovarian tissue cryopreservation without autotransplantation-what should be expected?

OBJECTIVE: To evaluate the delivery rate and to characterize patients following ovarian tissue cryopreservation (OTCP) who did not undergo auto-transplantation. METHODS AND MATERIALS: All consecutive cancer patients admitted to our IVF unit, from January 2004 to December 2015, who underwent OTCP for the purpose of fertility preservation without autotransplantation were analyzed. The cohort included 338 patients and was linked to the National Live Birth registry of the Israel Ministry of Health in order to determine whether the women delivered following the cancer diagnosis. MAIN OUTCOME MEASURES: Delivery rate following OTCP without autotransplantation. RESULTS: During 6.4 years of follow-up, 30% of the patients delivered, with no differences in gravity, age at first diagnosis of cancer, type of malignancy, or the prevalence of relapse of malignancy between those who delivered and those who did not. Moreover, in multivariate analysis, those undergoing OTCP before the age of 30 and those suffering from breast cancer had significantly higher odds to conceive and deliver following cancer treatment without the need of autotransplantation. CONCLUSIONS: Further studies are required to elucidate the appropriate subgroup of patients with breast cancer under the age of 30 years, who will need OTCP. This information might aid both fertility specialists' counseling and their oncological patients in pursuing the appropriate fertility preservation strategy.

Oncofertility: Pharmacological Protection and Immature Testicular Tissue (ITT)-Based Strategies for Prepubertal and Adolescent Male Cancer Patients.

While the incidence of cancer in children and adolescents has significantly increased over the last decades, improvements made in the field of cancer therapy have led to an increased life expectancy for childhood cancer survivors. However, the gonadotoxic effect of the treatments may lead to infertility. Although semen cryopreservation represents the most efficient and safe fertility preservation method for males producing sperm, it is not feasible for prepubertal boys. The development of an effective strategy based on the pharmacological protection of the germ cells and testicular function during gonadotoxic exposure is a non-invasive preventive approach that prepubertal boys could benefit from. However, the progress in this field is slow. Currently, cryopreservation of immature testicular tissue (ITT) containing spermatogonial stem cells is offered to prepubertal boys as an experimental fertility preservation strategy by a number of medical centers. Several in vitro and in vivo fertility restoration approaches based on the use of ITT have been developed so far with autotransplantation of ITT appearing more promising. In this review, we discuss the pharmacological approaches for fertility protection in prepubertal and adolescent boys and the fertility restoration approaches developed on the utilization of ITT.

Fertility Preservation in Pediatric Subspecialties: A Pilot Needs Assessment Beyond Oncology.

Physicians from 6 non-oncology pediatric subspecialties were surveyed about fertility preservation (FP) to assess education/service needs. Almost all (96%; 25 of 26) reported having patients at risk of infertility; however, only 58% (15 of 26) had discussed FP with patients' families. Most subspecialists (92%; 23 of 25) would like access to an FP program. Our data support exploring the expansion of FP programs beyond oncology.

Clinical practice guidelines for fertility preservation in young women undergoing gonadotoxic treatment: an overview and critical appraisal of methodological quality and content.

RESEARCH QUESTION: What is the methodological quality and content of internationally available clinical practice guidelines (CPGs) on fertility preservation (FP) care in adult women? DESIGN: Internationally available CPGs on FP care in adult women were identified after conducting an extensive literature search and consulting (inter)national key experts. The methodological quality of the CPGs was appraised by an (inter)national panel of experts using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. The content of the best CPGs, scoring ≥60% for the domain 'Rigour of development' of the AGREE II instrument, was extracted and categorized according to their topic. RESULTS: Thirty of the 1808 documents found were included. After consulting (inter)national key experts, 30 CPGs were included, six of which scored ≥60% for their 'Rigour of development'. The number of FP-related topics discussed by these six CPGs ranged from 4 to 12. The number of recommendations provided by the CPGs on these topics varied. The number of topics to which ≥5 recommendations were dedicated ranged from 0 to 4 between CPGs. CONCLUSION: CPGs on the subject of FP care are available, but there is room for improvement in quality and content. Although written for use in daily practice, the CPGs can also be used to develop quality indicators to monitor the quality of current FP care or to evaluate future improvement initiatives.