3D culture of ovarian follicles in granular and nanofibrillar hydrogels.

3D culture of ovarian follicles in hydrogel matrices is an important emerging tool for basic scientific studies as well as clinical applications such as fertility preservation. For optimizing and scaling 3D culture of preantral follicles, there is a need for identifying biomaterial matrices that simplifies and improves the current culture procedures. At present, microencapsulation of follicles in alginate beads is the most commonly used approach. However, this technique involves notable manual handling and is best suited for encapsulation of single or several follicles. As a potential alternative, we here explore the suitability of different particle-based hydrogel matrices, where follicles can easily be introduced in tunable 3D environments, in large numbers. Specifically, we study the growth of secondary murine follicles in microgranular alginate and nanofibrillar cellulose matrices, with and without cell-binding cues, and map follicle growth against the viscoelastic properties of the matrices. We cultured follicles within the particle-based hydrogels for 10 days and continuously monitored their size, survival, and tendency to extrude oocytes. Interestingly, we observed that the diameter of the growing follicles increased significantly in the particle-based matrices, as compared to state-of-the-art alginate micro-encapsulation. On the other hand, the follicles displayed an increased tendency for early oocyte extrusion in the granular matrices, leading to a notable reduction in the number of intact follicles. We propose that this may be caused by impaired diffusion of nutrients and oxygen through thicker matrices, attributable to our experimental setup. Still, our findings suggest that viscoelastic, granular hydrogels represent promising matrices for 3D culture of early-stage ovarian follicles. In particular, these materials may easily be implemented in advanced culturing devices such as micro-perfusion systems.

Exploring the effect of platelet-rich plasma on vascularization and survival of follicles in xenotransplanted human ovarian tissue.

RESEARCH QUESTION: Do platelet-rich plasma (PRP) products, specifically human platelet lysate (hPL) and umbilical cord plasma, enhance vascularization and follicular survival in human ovarian tissue transplanted to immunodeficient mice? DESIGN: Human ovarian tissue was transplanted to subcutaneous pockets in nude mice, followed by daily injections for 6 days of PRP or saline at the transplantation sites. After a grafting period of 3 and 6 days, vascularization was assessed using CD-31 quantification, and gene expression of angiogenic markers (VEGF/Vegf) together with apoptosis-related genes (BAX/BCL-2), oxidative stress markers (HMOX-1/Hmox-1) and pro-inflammatory markers (Il-1ß/Il-6/Tnf-α) was quantitively analysed. Follicle density was analysed in the grafts after 4 weeks. Additionally, a pilot study was conducted exploring the suitability of ultrasound scanning for assessing survival and vascularization in ovarian tissue xenografted to mice. RESULTS: Although there was a significant increase in the CD-31 area from day 3 to day 6 post-grafting, there were no significant differences between the hPL and control groups. Gene expression analysis revealed significant down-regulation of VEGF from day 3 to day 6 for both the hPL and control groups, and significant up-regulation of BAX/BCL-2 in the hPL group compared with the controls. The follicle density showed no significant differences in the hPL group and UCP groups compared with the controls. Furthermore, ultrasound biomicroscopy provided valuable insights into graft morphology, necrotic areas and blood flow, suggesting its potential as a monitoring tool. CONCLUSIONS: Despite the angiogenic properties of PRP, this study was unable to demonstrate a significant impact of hPL on vascularization or of hPL and UCP on follicular survival in xenotransplanted human ovarian tissue.

Interactive medical and safety monitoring in clinical trials with clinDataReview: a validated and open-source reporting tool.

Continuous medical and safety monitoring of subject data during a clinical trial is a critical part of evaluating the safety of trial participants and as such is governed by protocol procedures and regulatory guidelines to meet the trial's intended objectives. We present an open-source validated graphical tool (clinDataReview R package) which provides access to the trial data with drill-down to individual patient profiles. The tool incorporates functionalities that facilitate detection of error and data inconsistencies requiring follow-up. It supports regular medical monitoring and oversight as well as safety monitoring committees with interactive tables and listings alongside graphical visualizations of the primary safety data in reports. An implementation example is given where the tool is used to deliver validated outputs following FDA/EMA guidelines. As such, this tool enables a more efficient, interactive, and reproducible review of safety data collected during an ongoing clinical trial.

Spread-out Bragg peak FLASH: quantifying normal tissue toxicity in a murine model.

Objective: A favorable effect of ultra-high dose rate (FLASH) radiation on normal tissue-sparing has been indicated in several preclinical studies. In these studies, the adverse effects of radiation damage were reduced without compromising tumor control. Most studies of proton FLASH investigate these effects within the entrance of a proton beam. However, the real advantage of proton therapy lies in the Spread-out Bragg Peak (SOBP), which allows for giving a high dose to a target with a limited dose to healthy tissue at the entrance of the beam. Therefore, a clinically relevant investigation of the FLASH effect would be of healthy tissues within a SOBP. Our study quantified the tissue-sparing effect of FLASH radiation on acute and late toxicity within an SOBP in a murine model. Material/Methods: Radiation-induced damage was assessed for acute and late toxicity in the same mice following irradiation with FLASH (Field dose rate of 60 Gy/s) or conventional (CONV, 0.34 Gy/s) dose rates. The right hindleg of unanesthetized female CDF1 mice was irradiated with single-fraction doses between 19.9-49.7 Gy for CONV and 30.4-65.9 Gy for FLASH with 5-8 mice per dose. The leg was placed in the middle of a 5 cm SOBP generated from a mono-energetic beam using a 2D range modulator. Acute skin toxicity quantified by hair loss, moist desquamation and toe separation was monitored daily within 29 days post-treatment. Late toxicity of fibrotic development measured by leg extendibility was monitored biweekly until 30 weeks post-treatment. Results: Comparison of acute skin toxicity following radiation indicated a tissue-sparing effect of FLASH compared to conventional single-fraction radiation with a mean protection ratio of 1.40 (1.35-1.46). Fibrotic development similarly indicated normal tissue sparing with a 1.18 (1.17-1.18) protection ratio. The acute skin toxicity tissue sparing was similar to data from entrance-beam irradiations of Sørensen et al. (4). Conclusion: Full dose-response curves for acute and late toxicity after CONV and FLASH radiation were obtained. Radiation within the SOBP retains the normal-tissue-sparing effect of FLASH with a dose-modifying factor of 40% for acute skin damage and 18% for fibrotic development.

Male fertility restoration: in vivo and in vitro stem cell-based strategies using cryopreserved testis tissue: a scoping review.

IMPORTANCE: Advances in the treatment of childhood cancer have significantly improved survival rates, with more than 80% of survivors reaching adulthood. However, gonadotoxic cancer treatments endanger future fertility, and prepubertal males have no option to preserve fertility by sperm cryopreservation. In addition, boys with cryptorchidism are at risk of compromised fertility in adulthood. OBJECTIVE: To investigate current evidence for male fertility restoration strategies, explore barriers to clinical implementation, and outline potential steps to overcome these barriers, a scoping review was conducted. This knowledge synthesis is particularly relevant for prepubertal male cancer survivors and boys with cryptorchidism. EVIDENCE REVIEW: The review was conducted after the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews criteria and previously published guidelines and examined studies using human testis tissue of prepubertal boys or healthy male adults. A literature search in PubMed was conducted, and 72 relevant studies were identified, including in vivo and in vitro approaches. FINDINGS: In vivo strategies, such as testis tissue engraftment and spermatogonial stem cell transplantation, hold promise for promoting cell survival and differentiation. Yet, complete spermatogenesis has not been achieved. In vitro approaches focus on the generation of male germ cells from direct germ cell maturation in various culture systems, alongside human induced pluripotent stem cells and embryonic stem cells. These approaches mark significant advancements in understanding and promoting spermatogenesis, but achieving fully functional spermatozoa in vitro remains a challenge. Barriers to clinical implementation include the risk of reintroducing malignant cells and introduction of epigenetic changes. CONCLUSION: Male fertility restoration is an area in rapid development. On the basis of the reviewed studies, the most promising and advanced strategy for restoring male fertility using cryopreserved testis tissue is direct testis tissue transplantation. RELEVANCE: This review identifies persistent barriers to the clinical implementation of male fertility restoration. However, direct transplantation of frozen-thawed testis tissue remains a promising strategy that is on the verge of clinical application.

Testis tissue cryopreservation may be considered in boys with cryptorchidism.

ABSTRACT: This study assessed the feasibility of testis tissue cryopreservation (TTC) for fertility preservation in prepubescent boys with cryptorchidism. From January 2014 to December 2022, the University Hospital of Copenhagen (Rigshospitalet, Copenhagen, Denmark) implemented TTC for 56 boys with cryptorchidism to preserve their reproductive potential. Testis tissue samples were collected during orchiopexy (32 cases) or at subsequent follow-up procedures (24 cases), necessitated by an increased risk of infertility as indicated by hormonal assessments and/or findings from initial surgical biopsies. Testis samples were procured for TTC and pathological analysis. The cohort had an average age of 1.3 (range: 0.3-3.8) years at the time of orchiopexy, with 91.1% presenting bilateral cryptorchidism. The study revealed a median germ cell count of 0.39 (range: 0-2.88) per seminiferous tubule, with germ cells detected in 98.0% of the bilateral biopsies and 100% of the unilateral, indicating a substantial potential for fertility in these immature tissues. A dark spermatogonia (Ad) was detected in 37 out of 56 patients evaluated, with a median Ad spermatogonia count of 0.027 (range: 0.002-0.158) per seminiferous tubule. A total of 30.2% of the samples lacked Ad spermatogonia, indicative of potential gonadotrophin insufficiency. The median hormone levels measured were as follows: follicle-stimulating hormone (FSH) at 0.69 (range: 0.16-2.5) U l-1, luteinizing hormone (LH) at 0.21 (range: 0.05-3.86) U l-1, and inhibin B at 126 (range: 17-300) pg ml-1. Despite early orchiopexy, 20%-25% of boys with cryptorchidism remain at risk for future infertility, substantiating the necessity of TTC as a precaution. The study highlights the need for refined predictive techniques to identify boys at higher risk of future infertility.

Recombination and polarity effects of Farmer chambers in a strong magnetic field.

PURPOSE: Ionisation chamber based reference dosimetry in magnetic resonance linear accelerators (MRL) aimed for radiotherapy requires correction for recombination losses. Published studies have found that such corrections can be carried out using the two-voltage method. These studies have, however, not included comparison with recombination corrections based on the Niatel method, which can be seen as a robust reference method due to its clear separation of initial and volume recombination and its explicit account of the pulsed nature of the dose delivery. The primary objective of this work therefore was to carry out such a comparison. MATERIALS AND METHODS: Four Farmer-type chambers (PTW-30006 and PTW-30013) were placed in a water phantom in 1.5 T Elekta Unity MRL. The chambers were oriented antiparallel or perpendicular to the static magnetic field B0 and irradiated at a source-to-surface distance of 133.5 cm with a 10 × 10 cm2 field size. RESULTS: The two-voltage method gave results in agreement (within 0.1%) with the recombination corrections derived from the Niatel method. The recombination corrections from three Niatel parameter sets (one based on a Varian Truebeam and two obtained directly in the MRL) deviated less than 0.1% from each other. A systematic shift in the recombination correction of less than 0.05% was observed if polarity corrections were not applied. CONCLUSIONS: The study supports the use of the two-voltage method in MRLs based on its excellent agreement with the Niatel method. This work, therefore, complements existing knowledge as previous studies have not included a comparison with the Niatel method.

Exploring the biology of ctDNA release in colorectal cancer.

BACKGROUND: Circulating tumor DNA (ctDNA) has emerged as a promising tool for early cancer detection and minimal residual disease monitoring. However, the biology underlying ctDNA release and its variation across cancer types and histologies remains poorly understood. This study investigated the biology behind ctDNA shedding in colorectal cancer. METHODS: The study included a local cohort of 747 stage I-III colorectal cancer patients. All patients had ctDNA measurement prior to treatment and extensive clinical data. Primary tumor RNA sequencing and whole exome sequencing was performed in 95 and 652 patients respectively. Additionally, the study evaluated 89 non-small cell lung cancer patients from the TRACERx cohort, comprising primary tumor RNA sequencing and ctDNA measurement. RESULTS: We found tumor size and proliferative capacity to be key factors associated with ctDNA shedding in colorectal cancer. Furthermore, we found that the secretory and CMS3 colorectal cancer subtypes exhibited lower ctDNA shedding, while microsatellite instability (MSI) tumors had higher levels of ctDNA. Mutational analysis did not reveal any genes or pathways associated with ctDNA shedding in colorectal cancer. A comparison of transcriptomic profiles across multiple cancer types demonstrated that colorectal cancer and lung squamous cell carcinoma tumors shared a high-proliferative ctDNA shedding phenotype, while lung adenocarcinoma tumors displayed a distinct low-proliferative subgroup. Additionally, proliferation levels correlated with ctDNA detection sensitivity across multiple cancer types. CONCLUSION: These findings suggest that tumor size and proliferative capacity are drivers of ctDNA release in colorectal cancer and provide insights into the biology of ctDNA shedding on a pan-cancer level.

Proton FLASH: Impact of Dose Rate and Split Dose on Acute Skin Toxicity in a Murine Model.

PURPOSE: Preclinical studies have shown a preferential normal tissue sparing effect of FLASH radiation therapy with ultra-high dose rates. The aim of the present study was to use a murine model of acute skin toxicity to investigate the biologic effect of varying dose rates, time structure, and introducing pauses in the dose delivery. METHODS AND MATERIALS: The right hind limbs of nonanaesthetized mice were irradiated in the entrance plateau of a pencil beam scanning proton beam with 39.3 Gy. Experiment 1 was with varying field dose rates (0.7-80 Gy/s) without repainting, experiment 2 was with varying field dose rates (0.37-80 Gy/s) with repainting, and in experiment 3, the dose was split into 2, 3, 4, or 6 identical deliveries with 2-minute pauses. In total, 320 mice were included, with 6 to 25 mice per group. The endpoints were skin toxicity of different levels up to 25 days after irradiation. RESULTS: The dose rate50, which is the dose rate to induce a response in 50% of the animals, depended on the level of skin toxicity, with the higher toxicity levels displaying a FLASH effect at 0.7-2 Gy/s. Repainting resulted in higher toxicity for the same field dose rate. Splitting the dose into 2 deliveries reduced the FLASH effect, and for 3 or more deliveries, the FLASH effect was almost abolished for lower grades of toxicity. CONCLUSIONS: The dose rate that induced a FLASH effect varied for different skin toxicity levels, which are characterized by a differing degree of sensitivity to radiation dosage. Conclusions on a threshold for the dose rate needed to obtain a FLASH effect can therefore be influenced by the dose sensitivity of the used endpoint. Splitting the total dose into more deliveries compromised the FLASH effect. This can have an impact for fractionation as well as for regions where 2 or more FLASH fields overlap within the same treatment session.

Whole-genome Mutational Analysis for Tumor-informed Detection of Circulating Tumor DNA in Patients with Urothelial Carcinoma.

BACKGROUND AND OBJECTIVE: Circulating tumor DNA (ctDNA) can be used for sensitive detection of minimal residual disease (MRD). However, the probability of detecting ctDNA in settings of low tumor burden is limited by the number of mutations analyzed and the plasma volume available. We used a whole-genome sequencing (WGS) approach for ctDNA detection in patients with urothelial carcinoma. METHODS: We used a tumor-informed WGS approach for ctDNA-based detection of MRD and evaluation of treatment responses. We analyzed 916 longitudinally collected plasma samples from 112 patients with localized muscle-invasive bladder cancer who received neoadjuvant chemotherapy (NAC) before radical cystectomy. Recurrence-free survival (primary endpoint), overall survival, and ctDNA dynamics during NAC were assessed. KEY FINDINGS AND LIMITATIONS: We found that WGS-based ctDNA detection is prognostic for patient outcomes with a median lead time of 131 d over radiographic imaging. WGS-based ctDNA assessment after radical cystectomy identified recurrence with sensitivity of 91% and specificity of 92%. In addition, genomic characterization of post-treatment plasma samples with a high ctDNA level revealed acquisition of platinum therapy-associated mutational signatures and copy number variations not present in the primary tumors. The sequencing depth is a limitation for studying tumor evolution. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our results support the use of WGS for ultrasensitive ctDNA detection and highlight the possibility of plasma-based tracking of tumor evolution. WGS-based ctDNA detection represents a promising option for clinical use owing to the low volume of plasma needed and the ease of performing WGS, eliminating the need for personalized assay design. PATIENT SUMMARY: Detection of tumor DNA in blood samples from patients with cancer of the urinary tract is associated with poorer outcomes. Disease recurrence after surgery can be identified by the presence of tumor DNA in blood before it can be detected on radiography scans.

In vitro fertilization outcome based on the detailed early luteal phase trajectory of hormones: a prospective cohort study.

BACKGROUND: Ovarian stimulation and the use of human chorionic gonadotropin (hCG) for triggering oocyte maturation in women undergoing in vitro fertilisation (IVF) introduces several differences in luteal phase hormone levels compared with natural cycles that may negatively impact on endometrial receptivity and pregnancy rates after fresh embryo transfer. Exogenous luteal phase support is given to overcome these issues. The suitability of a pragmatic approach to luteal phase support is not known due to a lack of data on early phase luteal hormone levels and their association with fertility outcomes during IVF with fresh embryo transfer. This study determined early luteal phase profiles of serum progesterone, 17-hydroxyprogesterone and hCG, and associations between hormone levels/hormone level profile after hCG trigger and the live birth rate in women undergoing IVF with fresh embryo transfer. METHODS: This prospective single center, cohort study was conducted in Vietnam from January 2021 to December 2022. Women aged 18-38 years with normal ovarian reserve and undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone antagonist protocol were included. Serum hormone levels were determined before trigger, at 12, 24 and 36 h after hCG, and daily from 1 to 6 days after oocyte pick-up. Serum hormone level profiles were classified as lower or upper. The primary outcome was live birth rate based on early luteal phase hormone level profile. RESULTS: Ninety-five women were enrolled. Live birth occurred in 19/69 women (27.5%) with a lower progesterone profile and 13/22 (59.1%) with an upper progesterone profile (risk ratio [RR] 2.15; 95% confidence interval [CI] 1.28-3.60), and in 6/31 (19.4%) versus 26/60 (43.3%) with a lower versus upper serum 17-hydroxyprogesterone profile (RR 2.24; 95% CI 1.03-4.86). Nearly 20% of women had peak progesterone concentration on or before day 3 after oocyte pick-up, and this was associated with significantly lower chances of having a life birth. CONCLUSIONS: These data show the importance of proper corpus luteum function with sufficient progesterone/17-hydroxyprogesterone production for achievement of pregnancy and to maximize the chance of live birth during IVF. TRIAL REGISTRATION: NCT04693624 ( www. CLINICALTRIALS: gov ).

Beyond basics: Key mutation selection features for successful tumor-informed ctDNA detection.

Tumor-informed mutation-based approaches are frequently used for detection of circulating tumor DNA (ctDNA). Not all mutations make equally effective ctDNA markers. The objective was to explore if prioritizing mutations using mutational features-such as cancer cell fraction (CCF), multiplicity, and error rate-would improve the success rate of tumor-informed ctDNA analysis. Additionally, we aimed to develop a practical and easily implementable analysis pipeline for identifying and prioritizing candidate mutations from whole-exome sequencing (WES) data. We analyzed WES and ctDNA data from three tumor-informed ctDNA studies, one on bladder cancer (Cohort A) and two on colorectal cancer (Cohorts I and N). The studies included 390 patients. For each patient, a unique set of mutations (median mutations/patient: 6, interquartile 13, range: 1-46, total n = 4023) were used as markers of ctDNA. The tool PureCN was used to assess the CCF and multiplicity of each mutation. High-CCF mutations were detected more frequently than low-CCF mutations (Cohort A: odds ratio [OR] 20.6, 95% confidence interval [CI] 5.72-173, p = 1.73e-12; Cohort I: OR 2.24, 95% CI 1.44-3.52, p = 1.66e-04; and Cohort N: OR 1.78, 95% CI 1.14-2.79, p = 7.86e-03). The detection-likelihood was additionally improved by selecting mutations with multiplicity of two or above (Cohort A: OR 1.55, 95% CI 1. 14-2.11, p = 3.85e-03; Cohort I: OR 1.78, 95% CI 1.23-2.56, p = 1.34e-03; and Cohort N: OR 1.94, 95% CI 1.63-2.31, p = 2.83e-14). Furthermore, selecting the mutations for which the ctDNA detection method had the lowest error rates, additionally improved the detection-likelihood, particularly evident when plasma cell-free DNA tumor fractions were below 0.1% (p = 2.1e-07). Selecting mutational markers with high CCF, high multiplicity, and low error rate significantly improve ctDNA detection likelihood. We provide free access to the analysis pipeline enabling others to perform qualified prioritization of mutations for tumor-informed ctDNA analysis.

Error-Corrected Deep Targeted Sequencing of Circulating Cell-Free DNA from Colorectal Cancer Patients for Sensitive Detection of Circulating Tumor DNA.

Circulating tumor DNA (ctDNA) is a promising biomarker, reflecting the presence of tumor cells. Sequencing-based detection of ctDNA at low tumor fractions is challenging due to the crude error rate of sequencing. To mitigate this challenge, we developed ultra-deep mutation-integrated sequencing (UMIseq), a fixed-panel deep targeted sequencing approach, which is universally applicable to all colorectal cancer (CRC) patients. UMIseq features UMI-mediated error correction, the exclusion of mutations related to clonal hematopoiesis, a panel of normal samples for error modeling, and signal integration from single-nucleotide variations, insertions, deletions, and phased mutations. UMIseq was trained and independently validated on pre-operative (pre-OP) plasma from CRC patients (n = 364) and healthy individuals (n = 61). UMIseq displayed an area under the curve surpassing 0.95 for allele frequencies (AFs) down to 0.05%. In the training cohort, the pre-OP detection rate reached 80% at 95% specificity, while it was 70% in the validation cohort. UMIseq enabled the detection of AFs down to 0.004%. To assess the potential for detection of residual disease, 26 post-operative plasma samples from stage III CRC patients were analyzed. From this we found that the detection of ctDNA was associated with recurrence. In conclusion, UMIseq demonstrated robust performance with high sensitivity and specificity, enabling the detection of ctDNA at low allele frequencies.

Corrigendum: Dose-dependent stimulation of human follicular steroidogenesis by a novel rhCG during ovarian stimulation with fixed rFSH dosing.

[This corrects the article DOI: 10.3389/fendo.2022.1004596.].

Investigation of luteal HCG supplementation in GnRH-agonist-triggered fresh embryo transfer cycles: a randomized controlled trial.

RESEARCH QUESTION: Does splitting the human chorionic gonadotrophin (HCG) support in IVF cycles triggered by a gonadotrophin-releasing hormone agonist result in a better progesterone profile? DESIGN: Randomized controlled three-arm study, performed at the Fertility Clinic, Odense University Hospital, Denmark. Patients with 12-25 follicles ≥12 mm were randomized into three groups: Group 1 - ovulation triggered with 6500 IU HCG; Group 2 - ovulation triggered with 0.5 mg GnRH agonist, followed by 1500 IU HCG on the day of oocyte retrieval (OCR); and Group 3 - ovulation triggered with 0.5 mg GnRH agonist, followed by 1000 IU HCG on the day of OCR and 500 IU HCG on OCR + 5. All groups received 180 mg vaginal progesterone. Progesterone concentrations were analysed in eight blood samples from each patient. RESULTS: Sixty-nine patients completed the study. Baseline and laboratory data were comparable. Progesterone concentration peaked on OCR + 4 in Groups 1 and 2, and peaked on OCR + 6 in Group 3. On OCR + 6, the progesterone concentration in Group 2 was significantly lower compared with Groups 1 and 3 (P = 0.003 and P < 0.001, respectively). On OCR + 8, the progesterone concentration in Group 3 was significantly higher compared with the other groups (both P<0.001). Progesterone concentrations were significantly higher in Group 3 from OCR + 6 until OCR + 14 compared with the other groups (all P ≤ 0.003). Four patients developed ovarian hyperstimulation syndrome in Group 3. CONCLUSION: Sequential HCG support after a GnRH agonist trigger provides a better progesterone concentration in the luteal phase.

Dynamics of IGF signalling during the ovulatory peak in women undergoing ovarian stimulation.

CONTEXT: IGF signalling is known to affect human ovarian follicular function during growth and development. However, the role of the IGF system is unknown during the ovulatory peak, which is characterized by profound changes in granulosa cell (GCs) mitosis and function. OBJECTIVE: How is the IGF system expressed and regulated during the midcycle surge in women? DESIGN: Follicular fluid (FF) and granulosa cells (GCs) were collected during the ovulatory peak from two specific time-points. One sample was obtained before oocyte pick up (OPU): before ovulation trigger (OT) (T = 0 h) or at 12, 17, or 32 h after OT, and one sample was obtained at OPU 36 h after OT. SETTING: University hospital. PATIENTS/PARTICIPANTS: Fifty women undergoing ovarian stimulation were included. MAIN OUTCOME MEASURE: Gene expression profiles were assessed by microarray analysis of GCs. IGF-related proteins in the FF were assessed by using immunoassays or by determination of activity with a proteinase assay. RESULTS: Expression of proteins promoting IGF activity (i.e., IGF2, PAPPA, and IRS1) together with proliferation markers were downregulated on a transcriptional level in GCs after OT, whereas proteins inhibiting the IGF signal (i.e., IGFBPs, IGF2R, and STC1) were upregulated. STC1 gene expression and protein levels were greatly upregulated after OT with a parallel steep downregulation of PAPP-A proteolytic activity. CONCLUSIONS: These data suggest that downregulation of IGF signalling mediated by increased STC1 expression is instrumental for the sudden cessation in GC proliferation and onset of differentiation during the ovulatory peak.

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.

Incidence of late recurrence and second primary cancers 5-10 years after non-metastatic colorectal cancer.

The fraction of patients who are cancer-free survivors 5 years after curative-intended surgery for colorectal cancer (CRC) is increasing, suggesting that extending surveillance beyond 5 years may be indicated. Here we estimate the incidence of late recurrence, metachronous CRC, and second primary cancers 5-10 years postoperative. All patients resected for UICC stage I-III CRC in Denmark through 2004-2013 were identified. Through individual-level linkage of nationwide health registry data, recurrence status was determined using a validated algorithm. Cancer-free survivors 5 years after surgery, were included. Cumulative incidence functions (CIF) of late recurrence, metachronous CRC, and second primary cancer 5-10 years postoperative were constructed. Subdistribution hazards ratios (sHR) were computed using Fine-Gray regression. Among 8883 patients, 370 developed late recurrence (5-10-year CIF = 4.1%, 95%CI: 3.7%-4.6%), 270 metachronous CRC (5-10-year CIF = 3.0%, 95%CI: 2.7%-3.4%), and 635 a second primary cancer (5-10-year CIF = 7.2%, 95%CI: 6.7%-7.7%). The risk of late recurrence was reduced for patients operated in 2009-2013 compared to 2004-2008 (2.9% vs. 5.6%, sHR = 0.52, 95% CI: 0.42-0.65). The risk of metachronous CRC was likewise reduced from 4.1% to 2.1% (sHR = 0.50, 95%CI: 0.39-0.65). While the risk of second primary cancer did not change between 2009-2013 and 2004-2008 (7.1% vs. 7.1%, sHR = 0.98, 95% CI: 0.84-1.15). Using nation-wide 10-year follow-up data, we document that the incidences of late recurrence and metachronous CRC are low and decreasing from 2004 to 2013. Thus, despite increasing numbers of long-term cancer survivors, the data do not advocate for extending CRC-specific surveillance beyond 5 years.

Incidence of Recurrence and Time to Recurrence in Stage I to III Colorectal Cancer: A Nationwide Danish Cohort Study.

Importance: Management of colorectal cancer (CRC) has been updated continuously over the past 2 decades. While the combination of these initiatives has had implications for improved survival, the implications for rates of recurrence remain unexplored. Objective: To ascertain the rates of recurrence and describe time to recurrence within 5 years of surgery with curative intent for stages I to III CRC. Design, Setting, and Participants: This cohort study used the Danish Colorectal Cancer Group Database to identify patients with Union for International Cancer Control (UICC) stages I to III CRC who underwent primary surgery between January 1, 2004, and December 31, 2019. They were followed up until recurrence (event), death (competing event), diagnosis of a second cancer (competing event), emigration (censoring event), 5 years postoperatively (censoring event), or January 1, 2023 (censoring event), whichever came first. Recurrence status was ascertained through individual-level linked data from the Danish Cancer Registry, Danish National Patient Registry, and Danish Pathology Registry using a validated algorithm. Data were analyzed from January 1 to August 8, 2023. Exposure: Primary surgery performed during 3 calendar periods (2004-2008, 2009-2013, and 2014-2019) stratified by tumor site (colon or rectum) and UICC stage (I, II, and III). Main Outcomes and Measures: Stage-specific 5-year recurrence reported as the cumulative incidence function (CIF) of recurrence, the association between calendar period of primary surgery and recurrence risk reported as subdistribution hazard ratios (sHRs), and the time from surgery to recurrence. Results: Of the 34 166 patients with UICC stages I to III CRC (median [IQR] age, 70 [62-77] years); 18 552 males [54.3%]) included in the study, 7027 developed recurrence within 5 years after the primary surgery. For colon cancer, the 5-year CIF of recurrence decreased over the 3 calendar periods from 16.3% to 6.8% for UICC stage I, from 21.9% to 11.6% for UICC stage II, and from 35.3% to 24.6% for UICC stage III colon cancer. For rectal cancer, the 5-year CIF decreased over the 3 periods from 19.9% to 9.5% for stage I, from 25.8% to 18.4% for stage II, and from 38.7% to 28.8% for stage III disease. Patients with stage III disease had a shorter time from surgery to recurrence compared with those with stage I disease (time ratio stage III vs stage I = 0.30; 95% CI, 0.28-0.32). Cancers detected through screening were associated with lower stage-adjusted risks of recurrence (sHR, 0.81; 95% CI, 0.73-0.91) compared with cancers not detected through screening. Conclusions and Relevance: In this cohort of patients with CRC, the risk of recurrence decreased in patients with stages I to III disease during the study period. Cancer detection by screening was associated with an even lower risk of recurrence. Time to recurrence differed according to UICC stage. Because the risk of recurrence was so low in selected patient groups, future research is warranted to explore risk-stratified surveillance protocols in patients with CRC.