Testicular development in the complete androgen insensitivity syndrome

Androgen Insensitivity Syndrome with Bilateral Gonadal Sertoli Cell Lesions, Sertoli-Leydig Cell Tumor, and Paratesticular Leiomyoma: A Case Report and First Systematic Literature Review

Androgen insensitivity syndrome (AIS) is a rare Mendelian disorder caused by mutations of the androgen receptor (AR) gene on the long arm of the X chromosome. As a result of the mutation, the receptor becomes resistant to androgens, and hence, karyotypically male patients (46,XY) carry a female phenotype. Their cryptorchid gonads are prone to the development of several types of tumors (germ cell, sex cord stromal, and others). Here, we report a 15-year-old female-looking patient with primary amenorrhea who underwent laparoscopic gonadectomy. Histologically, the patient's gonads showed Sertoli cell hamartomas (SCHs) and adenomas (SCAs) with areas of Sertoli-Leydig cell tumors (SLCTs) and a left-sided paratesticular leiomyoma. Rudimentary Fallopian tubes were also present. The patient's karyotype was 46,XY without any evidence of aberrations. Molecular genetic analysis of the left gonad revealed two likely germline mutations-a pathogenic frameshift deletion in the AR gene (c.77delT) and a likely pathogenic missense variant in the RAC1 gene (p.A94V). Strikingly, no somatic mutations, fusions, or copy number variations were found. We also performed the first systematic literature review (PRISMA guidelines; screened databases: PubMed, Scopus, Web of Science; ended on 7 December 2023) of the reported cases of patients with AIS showing benign or malignant Sertoli cell lesions/tumors in their gonads (n = 225; age: 4-84, mean 32 years), including Sertoli cell hyperplasia (1%), Sertoli cell nodules (6%), SCHs (31%), SCAs (36%), Sertoli cell tumors (SCTs) (16%), and SLCTs (4%). The few cases (n = 14, 6%; six SCAs, four SCTs, two SLCTs, and two SCHs) with available follow-up (2-49, mean 17 months) showed no evidence of disease (13/14, 93%) or died of other causes (1/14, 7%) despite the histological diagnosis. Smooth muscle lesions/proliferations were identified in 19 (8%) cases (including clearly reported rudimentary uterine remnants, 3 cases; leiomyomas, 4 cases). Rudimentary Fallopian tube(s) were described in nine (4%) cases. Conclusion: AIS may be associated with sex cord/stromal tumors and, rarely, mesenchymal tumors such as leiomyomas. True malignant sex cord tumors can arise in these patients. Larger series with longer follow-ups are needed to estimate the exact prognostic relevance of tumor histology in AIS.

Diuron-induced fetal Leydig cell dysfunction in in vitro organ cultured fetal testes

Diuron is a phenylurea herbicide widely used in the agricultural industry. In recent years, the risk of infertility and developmental defects has increased due to exposure to environmental pollutants. In this study, we investigated the toxicity of diuron in fetal mouse testes using three-dimensional organ cultures. Fetal testes derived from embryonic day (E) 14.5 were cultured with 200 µM diuron for 5 days. The results revealed that diuron did not impair fetal germ cell proliferation or the expression levels of germ cell markers such as Ddx4, Dazl, Oct 4, Nanog, Plzf, and TRA 98. Similarly, the gene or protein expression of the Sertoli cell markers Sox9 and Wt1 in diuron-exposed fetal testes did not change after 5 days of culture. In contrast, diuron increased fetal Leydig cell markers (FLC), Cyp11a1, Cyp17a1, Thbs2, and Pdgf α, and decreased adult Leydig cell (ALC) markers, Sult1e1, Hsd173, Ptgds, and Vcam1. However, 3-βHSD, an FLC and ALC marker, was consistently maintained upon exposure to diuron in fetal testes compared to non-treated groups. In conclusion, our study demonstrates that diuron negatively impacts Fetal Leydig cell development, although it does not affect germ and Sertoli cells.

Androgen insensitivity syndrome: a review

PURPOSE

Androgen insensitivity syndrome (AIS) is a disorder characterized by peripheral androgen resistance due to androgen receptor mutations in subjects with 46 XY karyotype. The severity of hormone resistance (complete, partial or mild) determines the wide spectrum of phenotypes.

METHODS

We performed a literature review on Pubmed focusing on etiopathogenesis, molecular alterations, and diagnostic-therapeutic management.

RESULTS

AIS is determined by a large variety of X-linked mutations that account for the wide phenotypic spectrum of subjects; it represents one of the most frequent disorders of sexual development (DSD). Clinical suspicion can arise at birth in partial AIS, due to the presence of variable degrees of ambiguity of the external genitalia, and at pubertal age in complete AIS, due to the development of female secondary sex characteristics, primary amenorrhea, and absence of female primary sex characteristics (uterus and ovaries). Laboratory tests showing elevated LH and testosterone levels despite mild or absent virilization may be helpful, but diagnosis can be achieved only after genetic testing (karyotype examination and androgen receptor sequencing). The clinical phenotype and especially the decision on sex assignment of the patient, if the diagnosis is made at birth or in the neonatal period, will guide the following medical, surgical and psychological management.

CONCLUSIONS

For the management of AIS, a multidisciplinary team consisting of physicians, surgeons, and psychologists is highly recommended to support the patient and his/her family on gender identity choices and subsequent appropriate therapeutic decisions.

Clinical outcomes and genotype-phenotype correlations in patients with complete and partial androgen insensitivity syndromes

PURPOSE

Androgen insensitivity syndrome (AIS) is a rare X-linked recessive disorder caused by unresponsiveness to androgens because of mutations in the AR gene. Here, we investigated the clinical outcomes and molecular spectrum of AR variants in patients with AIS attending a single academic center.

METHODS

This study included 19 patients with AIS who were confirmed by molecular analysis of AR. Clinical features and endocrinological findings were retrospectively collected, including presenting features, external genitalia, sex of rearing, timing of gonadectomy, pubertal outcomes, and sex hormone levels. Molecular analysis of AR was performed using Sanger, targeted gene panel, or whole-exome sequencing.

RESULTS

Among all 19 patients, 14 (74%) were classified as having complete AIS (CAIS), whereas 5 (26%) had partial AIS (PAIS). All patients with CAIS, and 3 patients with PAIS were reared as female. One patient with CAIS manifested a mixed germ cell tumor at the age of 30 years. Molecular analysis of AR identified 19 sequence variants; 12 (63%) were previously reported, and the remaining 7 (37%) were novel. Missense mutations were the most common type (12 of 19, 63%), followed by small deletions, nonsense mutations, an insertion, and a splice site mutation.

CONCLUSION

Here, we describe the clinical outcomes and molecular characteristics of 19 Korean patients with AIS. Patients with PAIS manifested various degrees of masculinization of the external genitalia. Nonsense and frameshift mutations were frequent in patients with CAIS, whereas patients with PAIS harbored exclusively missense mutations.

Differences of Sex Development: Current Issues and Controversies

Differences of sex development (DSD) encompass a broad range of conditions in which the development of chromosomal, gonadal, or anatomic sex is not typically male or female. Terms used to describe DSD are controversial, and continuously evolving. An individualized, multidisciplinary approach is key to both the diagnosis and management of DSD. Recent advances in DSD care include expanded genetic testing options, a more nuanced approach to gonadal management, and an emphasis on shared decision-making, particularly related to external genital surgical procedures. The timing of DSD surgery is currently being questioned and debated in both medical and advocacy/activism spheres.

A Baby With Complete Androgen Insensitivity Syndrome and the Fortuitous Discovery of 45,X/46,XY Mosaicism

Disorders of sex development (DSD) are caused by defects in the complex sexual differentiation cascade, resulting in discordance among an individual's genetic, gonadal, and genital sexes. It affects one in 4,500 live births. A wide spectrum of genital phenotypes can be found depending on the underlying pathogenic mechanism and the developmental stage that is affected. We herein report a newborn with female external genitalia but palpable gonads at labia majora with normal testicular function and structure, which is typical of complete androgen insensitivity syndrome (CAIS). The genetic study revealed 45,X/46,XY mosaicism and c.2081A>C missense androgen receptor gene mutation, indicating the likelihood of co-existing CAIS. This case demonstrated the importance of correlating genital phenotype and the underlying pathogenic mechanism, to provide appropriate management of DSD. Important considerations on managing the gonads about the risks of gonadal malignancies are also discussed.

R, Jha M, Joshi S, Teja CR. Bilateral Breast Phyllodes Tumor in Androgen Insensitivity Syndrome

Phyllodes is a rare tumor found exclusively in females. It can be classified into benign, intermediate, or malignant variety based on the aggressive nature of the disease. With adequate preoperative clinical assessment combined with histopathology and radiological investigations the adequate treatment strategy can be formulated to avoid future recurrences. Complete androgen insensitivity syndrome (CAIS) is associated with a genotypic male, which can be confirmed by karyotyping, with phenotypic female characteristics. The present case is the first case of bilateral breast phyllodes tumor in a patient with CAIS. Preoperative assessment was suggestive of bilateral phyllodes tumor with bilateral gonads in the inguinal region which was confirmed to be testis postoperatively on histopathological analysis. A brief case report with review of literature is presented.

Persistence of foetal testicular features in patients with defective androgen signalling

OBJECTIVE

Congenital defects of androgen synthesis or action in 46,XY individuals can result in impaired virilisation, despite the apparent testicular development. In a recent case, report of a young adult with complete androgen insensitivity syndrome (CAIS), tumourous gonadal tissue was shown to express HSD17B3 in Sertoli cells (SCs) and not in Leydig cells (LCs). This expression pattern differs from the typical adult human testis and resembles a foetal mouse testis, suggesting an underlying testicular development and function defect. Here, we investigate the effect of altered androgen signalling in gonads from five 46,XY individuals with defects in androgen synthesis or action.

METHODS

Gonadal tissue sections from four patients with CAIS, one with CYP17A1 deficiency, and one control were immunostained for LC developmental and steroidogenic markers. The expression of some of these markers during development was investigated by reanalysing previously published single-cell RNA sequencing (scRNA-seq) data from normal human testicular tissues.

RESULTS

All gonadal tissues from the patients show an exclusive expression of HSD17B3 in SCs and an expression of the foetal/immature LC marker DLK1 in a subset of LCs, suggesting an androgen-dependent differentiation defect of adult SCs and LCs. Furthermore, reanalysis of scRNA-seq data reveals an expression of HSD17B3 in foetal and neonatal SCs that is downregulated in adult SCs.

CONCLUSIONS

Androgen signalling may affect the differentiation of adults, but possibly not foetal SCs or LCs, and may induce a shift of testosterone production from the tubular compartment in the foetal phase to the interstitial compartment in the adult phase.

Identification of the Rare Ala871Glu Mutation in the Androgen Receptor Gene Leading to Complete Androgen Insensitivity Syndrome in an Adolescent Girl with Primary Amenorrhea

Complete Androgen Insensitivity Syndrome (CAIS) is a rare genetic condition by mutations in the androgen receptor (AR) gene resulting in target issue resistance to androgens and a female phenotype in genetically male individuals. A 16-year-old phenotypically female individual presented to our clinic with primary amenorrhea. Her clinical evaluation showed normal female external genitalia, Tanner III breast development and sparse pubic and axillary hair (Tanner stage II). Hormonal assessment revealed increased concentrations of Luteinizing Hormone (LH), Testosterone and Antimüllerian Hormone (AMH). Image studies detected no uterus or gonads, but a blind vagina and the karyotype was 46, XY. These findings suggested the diagnosis of CAIS, and genetic testing of the AR gene revealed a rare pathogenic mutation of cytosine to adenine (c.2612C>A) replacing alanine with glutamic acid at position 871 (p.Ala871Glu) in the AR, previously described once in two adult sisters. The patient underwent gonadectomy and received hormonal replacement therapy. This study expands the AR mutation database and shows the complexity and the importance of prompt diagnosis, proper management, and follow-up for CAIS patients, underlining the need for standardized protocols.

Malignant Gonadal Germ Cell Tumors (Other Than Pure Germinoma) in Patients With Disorders of Sex Development: A Report of 21 Cases Based Largely on the Collection of Dr Robert E. Scully, Illustrating a High Frequency of Yolk Sac Tumor With Prominent Hepatoid and Glandular Features

We describe 21 nonpure germinomatous gonadal germ cell tumors (9 with a germinoma component), all but 1 associated with gonadoblastoma, in patients with disorders of sex development who ranged from 7 to 36 years old (average, 20 y). Twenty patients were clinically described as phenotypic females with ambiguous genitalia/virilization and primary amenorrhea. The most common documented peripheral karyotype was 46,XY (10/12; 83%). Fifteen of 16 tumors with available clinicopathologic data were unilateral. They ranged from 7 to 30 cm (mean, 15.5 cm) and were solid and cystic with frequent necrosis and hemorrhage. Gonadoblastoma, in its classic (70%), dissecting (5%), or combined (25%) forms, was identified in all but 1. The malignant germ cell tumors were typically mixed except for 5 pure yolk sac tumors and 1 expansile gonadoblastoma with syncytiotrophoblast cells. When admixed, the most common component was yolk sac tumor (n=10), followed by germinoma (n=9), embryonal carcinoma (n=5), choriocarcinoma (n=4), immature teratoma (n=3), and teratoma (n=2). Typical morphologic patterns of yolk sac neoplasia, including reticular/microcystic, solid (including blastema-like), and endodermal sinus (Schiller-Duval bodies), were seen, as well as glandular (n=10) and hepatoid (n=6) differentiation, with cystically dilated glands and diffuse hepatoid morphology in 3 and 2 tumors, respectively. Two yolk sac tumors showed a sarcomatoid pattern. Somatic-type malignancies (alveolar rhabdomyosarcoma and low-grade spindle cell sarcoma, not otherwise specified) were identified in 1 case each. This is the first large series of germ cell tumors other than typical pure germinoma associated with gonadoblastoma. The high frequency of yolk sac tumor with glandular (especially cystic glandular) and hepatoid morphologies is noteworthy, and their presence should prompt further evaluation for an associated gonadoblastoma and possible disorder of sex development.

What Does Androgen Receptor Signaling Pathway in Sertoli Cells During Normal Spermatogenesis Tell Us?

Androgen receptor signaling pathway is necessary to complete spermatogenesis in testes. Difference between androgen binding location in Sertoli cell classifies androgen receptor signaling pathway into classical signaling pathway and non-classical signaling pathway. As the only somatic cell type in seminiferous tubule, Sertoli cells are under androgen receptor signaling pathway regulation via androgen receptor located in cytoplasm and plasma membrane. Androgen receptor signaling pathway is able to regulate biological processes in Sertoli cells as well as germ cells surrounded between Sertoli cells. Our review will summarize the major discoveries of androgen receptor signaling pathway in Sertoli cells and the paracrine action on germ cells. Androgen receptor signaling pathway regulates Sertoli cell proliferation and maturation, as well as maintain the integrity of blood-testis barrier formed between Sertoli cells. Also, Spermatogonia stem cells achieve a balance between self-renewal and differentiation under androgen receptor signaling regulation. Meiotic and post-meiotic processes including Sertoli cell - Spermatid attachment and Spermatid development are guaranteed by androgen receptor signaling until the final sperm release. This review also includes one disease related to androgen receptor signaling dysfunction named as androgen insensitivity syndrome. As a step further ahead, this review may be conducive to develop therapies which can cure impaired androgen receptor signaling in Sertoli cells.

Ultrasound of retained gonads in children and young women with androgen insensitivity syndrome

INTRODUCTION

Gonadal management in androgen insensitivity syndrome (AIS) patients has been controversial due to low risk of testicular cancer. Our study evaluated the role of ultrasound (US) in screening for malignancy in retained gonads in AIS patients.

METHODS

This was a retrospective study (2001-2020) of gonadal US in patients with AIS. Demographics and clinical information were retrieved from the medical records. US studies were reviewed for nodule presence, size, echotexture, and change on follow-up studies. When available, pathology correlation was performed. Two-tailed t-test was used to compare age and development of nodules clinically or on US examination.

RESULTS

13 patients were included with a median age was 9.9 years (range 3.8-18.4 years). In 11 patients, gonads were in the inguinal canals on either initial or follow-up US. No nodules were palpable on physical examination, but nodules were detected in ten testicles by US in five of 13 patients (41.7%). Presence of nodules was significantly (p = 0.0038) associated with older age. The largest nodule size varied from 0.4 to 2.2 cm (average 0.9 ± 0.5 cm) and most (7/10, 70%) were hypoechoic. Finding testicular nodules on US led to change in management in three patients; bilateral gonadectomies, unilateral gonadectomy, and gonadal excisional biopsies (Figure). Pathology demonstrated Sertoli hamartoma in these patients, and in an additional two patients who underwent post-puberty gonadectomy. No malignancy was found in any specimen.

DISCUSSION

Preservation of the gonads in children with AIS is associated with low risk for malignant transformation. The role of US surveillance of the gonads is unknown. In our series on 13 patients, most of the visualized 24 gonads (22/24, 91.7%) were localized in the groins in either the first or follow-up US studies. Nodules were detected in ten gonads in five of 13 patients (41.7%). Most of these gonads (8/10) had numerous nodules, most (7/10) were hypoechoic with average diameter of the largest nodule of 0.9 ± 0.5 cm. Pathology in 5 patients demonstrated Sertoli hamartomas in all of the gonads. No malignancy was found. In our series, gonadal nodules led to either gonadectomies or excisional biopsies in three patients. Our study has several limitations, related to the retrospective nature of the study and the small size of our series.

CONCLUSION

Multiple testicular nodules were commonly detected by US in AIS patients and were not associated with malignancy. Therefore, we are concerned that US screening can lead to unnecessary excisional biopsies and orchiectomies.

Disorders of sex development and female reproductive capacity: A literature review

Disorders of sex development (DSD) are a wide-ranging group of complex conditions that influence chromosomal, gonadal, and phenotypic sex. The prevalence of DSD is very low, but affected patients deserve individualized management to improve psychological, sexual, and reproductive outcomes. This review aims to clarify the fertility potential of DSD patients who can be reared as females and their chance of becoming pregnant, especially using assisted reproductive techniques (ART). Due to the effects of DSD on internal and external genital organs, these conditions result in varying degrees of fertility potential. Fertility rate depends on the phenotype and is inversely related to the severity of the disorder. Reproductive endocrinologists and infertility specialists must be considered active partners of the interdisciplinary treatment team. With current advances in ART, pregnancy is more achievable in patients who were considered infertile at first glance. Due to the complexity of the medical management in DSD patients, more studies should be conducted to conclusively suggest the best choice for improving their fertility potential.Abbreviations: AIS: Androgen Insensitivity Syndrome; AMH: Anti-Müllerian Hormone; ART: Assisted Reproductive Technology; ASRM: American Society for Reproductive Medicine; CAH: Congenital Adrenal Hyperplasia; CAIS: Complete Androgen Insensitivity Syndrome; DHT: Dihydrotestosterone; DSD: Disorders of Sexual Development; FSH: Follicle Stimulating Hormone; GD: Gonadal Dysgenesis; ICSI: Intracytoplasmic Sperm Injection; IUGR: Intrauterine Growth Restriction; IVF: In Vitro Fertilization; IVF-ET: IVF and Embryo Transfer; LH: Luteinizing Hormone; MGD: Mixed Gonadal Dysgenesis; MRI: Magnetic Resonance Imaging; MRKH: Mayer-Rokitansky-Kuster-Hauser; US: Ultrasonography; HSG: Hysterosalpingography; PAIS: Partial Androgen Insensitivity Syndrome; PGD: Preimplantation Genetic Diagnosis; POR: P450 Oxidoreductase; PROM: Premature Rupture of Membranes; TS: Turner Syndrome; 17β-HSD III: 17β-Hydroxysteroid Dehydrogenase III; 21-OHD: 21-hydroxylase deficiency; 5α-RD-2: 5α-reductase-2.

Testosterone-induced increase in libido in a patient with a loss-of-function mutation in the AR gene

SUMMARY

Complete androgen-insensitivity syndrome (CAIS), a disorder of sex development (46,XY DSD), is caused primarily by mutations in the androgen receptor (AR). Gonadectomy is recommended due to the increased risk of gonadoblastoma, however, surgical intervention is often followed by loss of libido. We present a 26-year-old patient with CAIS who underwent gonadectomy followed by a significant decrease in libido, which was improved with testosterone treatment but not with estradiol. Genetic testing was performed and followed by molecular characterization. We found that this patient carried a previously unidentified start loss mutation in the androgen receptor. This variant resulted in an N-terminal truncated protein with an intact DNA binding domain and was confirmed to be loss-of-function in vitro. This unique CAIS case and detailed functional studies raise intriguing questions regarding the relative roles of testosterone and estrogen in libido, and in particular, the potential non-genomic actions of androgens.

LEARNING POINTS

N-terminal truncation of androgen receptor can cause androgen-insensitivity syndrome. Surgical removal of testosterone-producing gonads can result in loss of libido. Libido may be improved with testosterone treatment but not with estradiol in some forms of CAIS. A previously unreported AR mutation - p.Glu2_Met190del (c.2T>C) - is found in a CAIS patient and results in blunted AR transcriptional activity under testosterone treatment.

Malignant Germ Cell Tumors and Their Precursor Gonadal Lesions in Patients with XY-DSD: A Case Series and Review of the Literature

The risk of gonadal germ cell tumors is increased over the lifetime of patients with XY-disorders of sex development (XY-DSD). The aim of this study was to evaluate clinical features and histopathological outcome after gonadectomy in patients with XY-DSD to assess the risk of malignant transformation to gonadal germ cell tumors. Thirty-five women treated for XY-DSD at our hospital between 2003 and 2020 were enrolled in this study. Twenty-seven (77%) underwent prophylactic gonadectomy, 10 (29%) at our department and 17 (48%) at external hospitals. Eight (23%) patients didn’t receive gonadectomy. Of the patients who underwent a surgical procedure at our hospital, two patients were diagnosed with a unilateral seminoma, one patient with a bilateral and one patient with a unilateral Sertoli cell adenoma. According to these findings, preventive gonadectomy in patients with XY-DSD should be taken into consideration. Guidelines concerning the necessity of gonadectomy to avoid malignant transformation are still lacking. The risk of malignant germ cell tumors from rudimentary gonads has not been investigated sufficiently to date, as it is mostly based on case series due to the rarity of the condition. In our study we retrospectively analyzed patients who partly underwent bilateral gonadectomy, aiming to fill this gap. Concerning the ideal point of time for gonadectomy, further studies with a higher number of patients are needed.

Dilemmas in management of osteoporosis in patients with complete androgen insensitivity syndrome

Complete androgen insensitivity syndrome (CAIS)-resulting in 46,XY karyotype, but female phenotype-is a disorder of sex development and primary amenorrhea, but its effect on bone mineral density (BMD) is singular and difficult to manage. Androgens are an important modulator of bone remodeling and health, and the androgen receptor (AR) is pivotal for signaling within the bone cells. CAIS results in a severely disrupted AR throughout the body, causing an elevated risk of early osteoporosis. Timing of gonadectomy and hormone replacement therapy protocols are not established, creating a wide variety of treatment plans and BMD profiles. Our objective is to report a patient with CAIS status post prepubertal orchiectomy that developed early osteoporosis and to describe the lack of optimal strategies and consensus available to improve bone health in this population. Additionally, our case illustrates the fact there are no guidelines advocating the use of newer drugs for osteoporosis in this population.

Complete androgen insensitivity syndrome with accelerated onset of puberty due to a Sertoli cell tumor

Complete androgen insensitivity syndrome (CAIS) is caused by mutations in the androgen receptor gene. Patients with this syndrome have a 46,XY karyotype, male gonads, and normal female external genitalia. While the pre-pubertal risk of developing gonadal tumors is low in these patients, it increases with age. Most gonadal tumors arise from germ cells; stromal cell tumors are uncommon. Herein, we report a CAIS patient with a feminizing Sertoli cell tumor. The patient presented at 8 yr of age with breast enlargement and growth acceleration, concomitant with elevated serum estradiol levels and suppressed serum gonadotropin levels; these findings were inconsistent with CAIS. The patient underwent gonadectomy at 10 yr of age, and histology demonstrated presence of a non-malignant Sertoli cell tumor in the right gonad. We conclude that this is the first reported case of CAIS with accelerated onset of puberty resulting from a Sertoli cell tumor.

Complete androgen insensitivity syndrome and risk of gonadal malignancy: systematic review

Complete androgen insensitivity syndrome (CAIS) is a rare condition characterized by 46,XY karyotype, female external genitalia, absence of uterus, and testes located intra-abdominally, in the inguinal ring or in the labia majora. In the present study, the frequency of testicular malignancy in prepubertal and pubertal patients with CAIS who underwent gonadectomy or gonadal biopsy were evaluated. Systematic review was performed using electronic databases according to the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) guidelines. The samples included 15 articles published between 1998 and 2019. From a total of 456 patients who underwent gonadectomy or gonadal biopsy, 6.14% had a premalignant lesion and most were postpubertal (82.14%). A malignant lesion was found in 1.3% and all were postpubertal. Because the risk of malignancy is very low in prepubertal patients with CAIS, gonadectomy may be delayed until puberty is complete, allowing it to progress naturally; however, close follow-up of the patient is required.

Testicular dysgenesis syndrome and phthalate exposure: A review of literature

Endocrine disruptors are chemicals that interfere with the body's endocrine system and cause adverse effects in biological systems. Phthalates are a group of man-made chemicals which are mainly used as plasticizers and classified as endocrine disruptors. They are also used in cosmetic and personal care products as color or smell fixators. Moreover, phthalates are present in inks, adhesives, sealants, automobile parts, tools, toys, carpets, medical tubing and blood storage bags, and food packages. Pathological condition known as "testicular dysgenesis syndrome" (TDS) or "phthalate syndrome" is usually linked to phthalate exposure and is coined to describe the rise in alterations in reproductive health in men, such as reduced semen quality (decrease in sperm counts, sperm motility and increase in abnormal sperms), hypospadias, cryptorchidism, reduced anogenital distance and early-life testicular cancer. Phthalates are suggested to cause direct effect on gonadal and non-gonadal tissues, impair the differentiation and morphogenesis of seminiferous tubules and accessory sex organs and testicular cells (both Sertoli and Leydig cells), alter estradiol and/or testosterone levels, decrease insulin-like 3 (INSL3) peptide production, impair spermatogenesis and lead to epigenetic alterations, all of which may lead to TDS. This review will mainly focus on phthalates as causes of TDS and their mechanisms of action.

Sex determination, gonadal sex differentiation, and plasticity in vertebrate species

A diverse array of sex determination (SD) mechanisms, encompassing environmental to genetic, have been found to exist among vertebrates, covering a spectrum from fixed SD mechanisms (mammals) to functional sex change in fishes (sequential hermaphroditic fishes). A major landmark in vertebrate SD was the discovery of the SRY gene in 1990. Since that time, many attempts to clone an SRY ortholog from nonmammalian vertebrates remained unsuccessful, until 2002, when DMY/dmrt1by was discovered as the SD gene of a small fish, medaka. Surprisingly, however, DMY/dmrt1by was found in only 2 species among more than 20 species of medaka, suggesting a large diversity of SD genes among vertebrates. Considerable progress has been made over the last 3 decades, such that it is now possible to formulate reasonable paradigms of how SD and gonadal sex differentiation may work in some model vertebrate species. This review outlines our current understanding of vertebrate SD and gonadal sex differentiation, with a focus on the molecular and cellular mechanisms involved. An impressive number of genes and factors have been discovered that play important roles in testicular and ovarian differentiation. An antagonism between the male and female pathway genes exists in gonads during both sex differentiation and, surprisingly, even as adults, suggesting that, in addition to sex-changing fishes, gonochoristic vertebrates including mice maintain some degree of gonadal sexual plasticity into adulthood. Importantly, a review of various SD mechanisms among vertebrates suggests that this is the ideal biological event that can make us understand the evolutionary conundrums underlying speciation and species diversity.

Risk of gonadal neoplasia in patients with disorders/differences of sex development

BACKGROUND

Patients with disorders/differences of sex development (DSD), especially those possessing the Y chromosome, have a higher risk of gonadal germ-cell tumours (GCTs). We aimed to examine the incidence of different types of gonadal neoplasia and associated risk factors.

METHODS

A total of 1040 DSD patients aged ≥16 years participated in a cross-sectional multicentre European study (dsd-LIFE). Data on medical history were gathered from the patients' archival medical documents. A web-based questionnaire was filled out individually by the participants. A physical examination was performed in all, while ultrasonography of gonads was carried out in 214 and semen analysis was performed for 53 patients.

RESULTS

Germ-cell neoplasia was present in 12 % of patients with DSD and in 14 % of those with XY DSD. The highest risk (36 %) was observed in 46,XY patients with gonadal dysgenesis (GD): complete GD (33 %) and partial GD (23 %), but also in mixed GD (8 %) and complete androgen insensitivity syndrome (AIS) (6%). It was not reported in partial AIS, XX male, 46,XX DSD and congenital adrenal hyperplasia, Turner and Klinefelter syndromes, or in androgen biosynthesis defects. Benign sex cord-stromal tumours (Sertoli- and Leydig-cell tumours) were noted only in patients with complete AIS (3.1 %) and Klinefelter syndrome (14.3 %). A relationship between risk factors for GCT and gonadal neoplasia appearance, other than the Y chromosome, was not found.

CONCLUSION

Adult patients with GD and the Y chromosome have the highest risk of GCT and should be kept under thorough medical control and receive special medical follow-up to prevent the development of gonadal tumours.

Inguinal hernia in girls: A retrospective analysis of over 1000 patients

BACKGROUND

In girls with inguinal hernia, timing of surgical repair to prevent ovarian strangulation and screening for Androgen Insensitivity Syndrome (AIS) remain controversial. This study assesses the incidence of ovarian strangulation and AIS, and its associated risk factors.

METHODS

Electronic patient records were used to study girls aged 0-15 years who underwent inguinal hernia repair between 2000 and 2017. Patients with incomplete data were excluded. Risk factors were identified using logistic regression.

RESULTS

This study includes 1084 girls (median (IQR) age: 133.5 (14-281) weeks) who underwent 1132 hernia repairs (1015 unilateral, 117 bilateral) within a median (IQR) time interval of 12 (6-23) days following diagnosis. Hernia sac intraoperatively contained ovary in 235 (21.7%) patients, ovary was strangulated in 14 (6%). Risk factors for ovarian strangulation were younger gestational age (OR 0.49), higher birthweight (OR 32.18), and first presentation at the emergency department (OR 13.07). However data were partly missing. Ectopic testis was found in seven (0.6%) patients. Metachronous contralateral inguinal hernia and ipsilateral recurrence developed in 6.1% and 0.3%, respectively.

CONCLUSIONS

Ovarian hernia was diagnosed in 21.7%, and ovary was strangulated in 6%. No definite conclusions can be drawn regarding risk factors for strangulation and timing of surgery in girls with irreducible ovarian hernia.

LEVEL OF EVIDENCE

Level III.

Gonadoblastoma Y locus genes expressed in germ cells of individuals with dysgenetic gonads and a Y chromosome in their karyotypes include DDX3Y and TSPY

STUDY QUESTION

Which Y genes mapped to the 'Gonadoblastoma Y (GBY)' locus on human Y chromosome are expressed in germ cells of individuals with some Differences of Sexual Development (DSD) and a Y chromosome in their karyotype (DSD-XY groups)?

SUMMARY ANSWER

The GBY candidate genes DDX3Y and TSPY are expressed in the germ cells of DSD-XY patients from distinct etiologies: patients with mixed gonadal dysgenesis (MGD) and sex chromosome mosaics (45,X0/46,XY; 46,XX/46,XY); patients with complete androgen insensitivity (CAIS), patients with complete gonadal dysgenesis (CGD; e.g. Swyer syndrome).

WHAT IS KNOWN ALREADY

A GBY locus was proposed to be present on the human Y chromosome because only DSD patients with a Y chromosome in their karyotype have a high-although variable-risk (up to 55%) for germ cell tumour development. GBY was mapped to the proximal part of the short and long Y arm. TSPY located in the proximal part of the short Y arm (Yp11.1) was found to be a strong GBY candidate gene. It is expressed in the germ cells of DSD-XY patients with distinct etiologies but also in foetal and pre-meiotic male spermatogonia. However, the GBY region extends to proximal Yq11 and therefore includes probably more than one candidate gene.

STUDY DESIGN, SIZE, DURATION

Protein expression of the putative GBY candidate gene in proximal Yq11, DDX3Y, is compared with that of TSPY in serial gonadal tissue sections of 40 DSD-XY individuals from the three DSD patient groups (MGD, Complete Androgen Insensitivity Syndrome [CAIS], CGD) with and without displaying malignancy. Expression of OCT3/4 in the same tissue samples marks the rate of pluripotent germ cells.

PARTICIPANTS/MATERIALS, SETTING, METHOD

A total of 145 DSD individuals were analysed for the Y chromosome to select the DSD-XY subgroup. PCR multiplex assays with Y gene specific marker set score for putative microdeletions in GBY Locus. Immunohistochemical experiments with specific antisera mark expression of the GBY candidate proteins, DDX3Y, TSPY, in serial sections of the gonadal tissue samples; OCT3/4 expression analyses in parallel reveal the pluripotent germ cell fraction.

MAIN RESULTS AND THE ROLE OF CHANCE

Similar DDX3Y and TSPY protein expression patterns were found in the germ cells of DSD-XY patients from each subgroup, independent of age. In CAIS patients OCT3/4 expression was often found only in a fraction of these germ cells. This suggest that GBY candidate proteins are also expressed in the non-malignant germ cells of DSD-XY individuals like in male spermatogonia.

LIMITATIONS, REASONS FOR CAUTION

Variation of the expression profiles of GBY candidate genes in the germ cells of some DSD-XY individuals suggests distinct transcriptional and translational control mechanisms which are functioning during expression of these Y genes in the DSD-XY germ cells. Their proposed GBY tumour susceptibility function to transform these germ cells to pre-malignant GB/Germ Cell Neoplasia in Situ (GB/GCNIS) cells seems therefore to be limited and depending on their state of pluripotency.

WIDER IMPLICATIONS OF THE FINDINGS

These experimental findings are of general importance for each individual identified in the clinic with DSD and a Y chromosome in the karyotype. To judge their risk of germ cell tumour development, OCT3/4 expression analyses on their gonadal tissue section is mandatory to reveal the fraction of germ cells still being pluripotent. Comparative expression analysis of the GBY candidate genes can be helpful to reveal the fraction of germ cells with genetically still activated Y chromosomes contributing to further development of malignancy if at high expression level.

STUDY FUNDING/COMPETING INTEREST(S)

This research project was supported by a grant (01GM0627) from the BMBF (Bundesministerium für Bildung und Forschung), Germany to P.H.V. and B.B. The authors have no competing interests.

Disorders of Sex Development-Novel Regulators, Impacts on Fertility, and Options for Fertility Preservation

Disorders (or differences) of sex development (DSD) are a heterogeneous group of congenital conditions with variations in chromosomal, gonadal, or anatomical sex. Impaired gonadal development is central to the pathogenesis of the majority of DSDs and therefore a clear understanding of gonadal development is essential to comprehend the impacts of these disorders on the individual, including impacts on future fertility. Gonadal development was traditionally considered to involve a primary 'male' pathway leading to testicular development as a result of expression of a small number of key testis-determining genes. However, it is increasingly recognized that there are several gene networks involved in the development of the bipotential gonad towards either a testicular or ovarian fate. This includes genes that act antagonistically to regulate gonadal development. This review will highlight some of the novel regulators of gonadal development and how the identification of these has enhanced understanding of gonadal development and the pathogenesis of DSD. We will also describe the impact of DSDs on fertility and options for fertility preservation in this context.

Comparative Transcriptomics Analysis of Testicular miRNA from Cryptorchid and Normal Horses

Simple Summary

The testis is an important organ for mammals, and testicular microRNA expression is associated with male fertility to a certain extent. Cryptorchidism is the failure of one or both testes to descend into the scrotal sac. It is a common congenital malformation in horses. The major clinical consequence of this abnormality is impaired fertility. The expression of testicular microRNAs is influenced by many factors, including high temperature and disease, in cryptorchid horses. Here, we investigated the microRNA expression levels of normal and retained testes. Their expression patterns showed significant differences. In addition, we obtained comprehensive expression data for equine testicular microRNA, which is fundamental information for further analysis.

Abstract

In the biological process of testicular spermatogenesis, the expression and interaction of many genes are regulated by microRNAs (miRNAs). However, comparisons of miRNA expression between descended testes (DTs) and undescended testes (UDTs) are rarely done in horses. In this study, we selected two UDTs (CKY2b and GU4b) from Chakouyi (CKY) and Guanzhong (GU) horses and eight DTs (GU1–3, CKY1, CKY3, CKY2a, GU4a, and GU5). Three groups were compared to evaluate expression patterns of testicular miRNA in stallion testes. Group 1 compared normal CKY horses and GU horses (CKY1 and CKY3 vs. GU1–3). Group 2 (CKY2a and GU4a (DTs) vs. CKY2b and GU4b (UDTs)) and group 3 (GU1–3, CKY1, CKY3 (DTs) vs. CKY2b and GU4b (UDTs)) compared the expression levels in unilateral retained testes to normal testes. The results show that 42 miRNAs (7 upregulated and 35 downregulated) had significantly different expression levels in both comparisons. The expression levels of eca-miR-545, eca-miR-9084, eca-miR-449a, eca-miR-9024, eca-miR-9121, eca-miR-8908e, eca-miR-136, eca-miR-329b, eca-miR-370, and eca-miR-181b were further confirmed by quantitative real-time PCR assay. The target genes of differentially expressed miRNAs in three comparisons were predicted, and the functions were annotated. The putative target genes of the 42 co-differentially expressed miRNAs were annotated to 15 functional terms, including metal ion binding, GTPase activator activity, zinc ion binding, intracellular, cytoplasm, and cancer pathways, and osteoclast differentiation. Our data indicate that the differentially expressed miRNAs in undescended testis suggests a potential role in male fertility and a relationship with cryptorchidism in horses. The discovery of miRNAs in stallion testes might contribute to a new direction in the search for biomarkers of stallion fertility.

A Management Protocol for Gonad Preservation in Patients with Androgen Insensitivity Syndrome

Historically, individuals with androgen insensitivity syndrome (AIS) were managed with removal of gonadal tissue at various ages to avert the risk of gonadal malignancy. Recently, clinical practice changed, with gonadectomy being postponed until late adolescence. Adolescents and adults with complete AIS have questioned this approach. Additionally, testicular germ cell tumors are increasingly believed to be quite rare with rates as low as 0% in molecularly confirmed individuals with AIS. Gonadectomy deprives patients of the benefits of their endogenous hormones and potential fertility. Furthermore, human rights organizations advocate for deferring irreversible surgery in conditions known as differences of sex development, which includes AIS, to allow patient autonomy in decision-making. Recent literature supports an approach that uses risk stratification to manage gonads in AIS. Herein we review what is known about malignancy risk in the different subtypes of AIS and propose a management protocol for gonad retention.

Features of the fetal gonad in androgen synthesis in the postpubertal testis are preserved in complete androgen insensitivity syndrome due to a novel genetic splice site donor variant in androgen receptor gene intron 1

Mutations in the X-linked androgen receptor (AR) gene cause complete androgen insensitivity syndrome (CAIS). CAIS may cause congenital sexual development disorder, which frequently develops into testicular tumors. Here, we describe a novel splice-site intron 1 mutation in AR leading to improper splicing and AR protein absence in CAIS gonads. We characterized a patient's postpubertal gonadal steroidogenic enzyme expression profile. Localization of both CYP11A1 and CYP17A1 enzymes was restricted to both Leydig tumor cells and adjacent to tumor gonadal tissues. Sertoli cells of the CAIS gonad showed abundant HSD17B3 protein, which is an adult Leydig cell marker that enables the conversion of androstenedione to testosterone. Such HSD17B3 expression is typical for fetal-type Sertoli cells in rodents. The postpubertal CAIS gonad of our patient was completely devoid of androgen signaling pathway activity. Plausibly, the postpubertal Leydig cells consisted of two distinct cell populations: postpubertal fetal-type Leydig cells that persisted as androgen-independent cells and immature adult Leydig cells that failed to differentiate. Taken together, in this CAIS postpubertal testis, both Leydig and fetal-type Sertoli cells participated in testosterone production. Our results indicate the importance of molecular analysis as well as the characterization of steroidogenic enzyme profiling in the CAIS patient's gonad.

Ferredoxin 1b Deficiency Leads to Testis Disorganization, Impaired Spermatogenesis, and Feminization in Zebrafish

The roles of steroids in zebrafish sex differentiation, gonadal development, and function of the adult gonad are poorly understood. Herein, we used ferredoxin 1b (fdx1b) mutant zebrafish to explore such processes. Fdx1b is an essential electron-providing cofactor to mitochondrial steroidogenic enzymes, which are crucial for glucocorticoid and androgen production in vertebrates. Fdx1b-/- zebrafish mutants develop into viable adults in which concentrations of androgens and cortisol are significantly reduced. Adult fdx1b-/- mutant zebrafish display predominantly female secondary sex characteristics but may possess either ovaries or testes, confirming that androgen signaling is dispensable for testicular differentiation in this species, as previously demonstrated in androgen receptor mutant zebrafish. Adult male fdx1b-/- mutant zebrafish exhibit reduced characteristic breeding behaviors and impaired sperm production, resulting in infertility in standard breeding scenarios. However, eggs collected from wild-type females can be fertilized by the sperm of fdx1b-/- mutant males by in vitro fertilization. The testes of fdx1b-/- mutant males are disorganized and lack defined seminiferous tubule structure. Expression of several promale and spermatogenic genes is decreased in the testes of fdx1b-/- mutant males, including promale transcription factor sox9a and spermatogenic genes igf3 and insl3. This study establishes an androgen- and cortisol-deficient fdx1b zebrafish mutant as a model for understanding the effects of steroid deficiency on sex development and reproductive function. This model will be particularly useful for further investigation of the roles of steroids in spermatogenesis, gonadal development, and regulation of reproductive behavior, thus enabling further elucidation of the physiological consequences of endocrine disruption in vertebrates.

Establishing reproductive potential and advances in fertility preservation techniques for XY individuals with differences in sex development

BACKGROUND

Discordance between gonadal type and gender identity has often led to an assumption of infertility in patients with differences in sex development (DSD). However, there is now greater recognition of fertility being an important issue for this group of patients. Currently, gonadal tissue that may have fertility potential is not being stored for individuals with DSD and, where gonadectomy forms part of management, is often discarded. The area of fertility preservation has been predominantly driven by oncofertility which is a field dedicated to preserving the fertility of patients undergoing gonadotoxic cancer treatment. The use of fertility preservation techniques could be expanded to include individuals with DSD where functioning gonads are present.

METHODS

This is a systematic literature review evaluating original research articles and relevant reviews between 1974 and 2018 addressing DSD and fertility, in vitro maturation of sperm, and histological/ultrastructural assessment of gonadal tissue in complete and partial androgen insensitivity syndrome, 17β-hydroxysteroid dehydrogenase type 3 and 5α-reductase deficiency.

CONCLUSION

Successful clinical outcomes of ovarian tissue cryopreservation are paving the way for similar research being conducted using testicular tissue and sperm. There have been promising results from both animal and human studies leading to cryopreservation of testicular tissue now being offered to boys prior to cancer treatment. Although data are limited, there is evidence to suggest the presence of reproductive potential in the gonads of some individuals with DSD. Larger, more detailed studies are required, but if these continue to be encouraging, individuals with DSD should be given the same information, opportunities and access to fertility preservation as other patient groups.

[Progress on evaluation, diagnosis and management of disorders of sex development]

Disorders of sex development (DSD) refer to a group of diseases characterized by abnormal congenital development of chromosomes, gonad or genitals with different pathophysiological changes and clinical manifestations. DSD is more common in neonates and adolescents, and neonates often show genital abnormalities while adolescents show abnormal sexual development during puberty. It is the international consensus that the scope of DSD should include basic clinical evaluation (internal and external genitalia and endocrine hormones), diagnostic confirmation (chromosome, genetic diagnosis), psychological assessment for children and family, treatment (sex assignment, hormone replacement and surgical intervention), potential fertility protection and long-term follow-up, which require the expertise of pediatric endocrinology, pediatric urology, clinical psychology, genetic disciplines, medical images and other related disciplines; that is, individualized management of children with DSD requires an experienced multidisciplinary team (MDT). This article reviews the recent progress on the evaluation, diagnosis and management of disorders of sex development.

Female fertility preservation in DSD

Disorders of sex development (DSD) are a group of complex conditions that can affect chromosomal, gonadal, and/or phenotypical sex with a highly variable fertility potential amongst affected individuals. In this review we discuss fertility issues facing patients affected by DSD and Turner syndrome and summarise the literature on fertility and reproductive outcomes. We will also discuss fertility preservation prior to gonadotoxic treatment in adolescent and prepubertal girls. Future directions in fertility preservation and ethical issues will also be addressed. Fertility preserving options that are established include ovarian tissue and oocyte cryopreservation. However, in many of the DSDs fertility is not possible and the discussion may need to move toward alternative methods of creating a family such as gamete donation or surrogacy.

Primary gonadal failure

The term primary gonadal failure encompasses not only testicular insufficiency in 46,XY males and ovarian insufficiency in 46,XX females, but also those disorders of sex development (DSD) which result in gender assignment that is at variance with the genotype and gonadal type. In boys, causes of gonadal failure include Klinefelter and other aneuploidy syndromes, bilateral cryptorchidism, testicular torsion, and forms of 46,XY DSD such as partial androgen insensitivity. Causes in girls include Turner syndrome and other aneuploidies, galactosemia, and autoimmune ovarian failure. Iatrogenic causes in both boys and girls include the late effects of childhood cancer treatment, total body irradiation prior to bone marrow transplantation, and iron overload in transfusion-dependent thalassaemia. In this paper, a brief description of the physiology of testicular and ovarian development is followed by a section on the causes and practical management of gonadal impairment in boys and girls. Protocols for pubertal induction and post-pubertal hormone replacement - intramuscular, oral and transdermal testosterone in boys; oral and transdermal oestrogen in girls - are then given. Finally, current and future strategies for assisted conception and fertility preservation are discussed.

Different Clinical Presentations and Management in Complete Androgen Insensitivity Syndrome (CAIS)

Complete androgen insensitivity syndrome (CAIS) is an X-linked recessive genetic disorder resulting from maternally inherited or de novo mutations involving the androgen receptor gene, situated in the Xq11-q12 region. The diagnosis is based on the presence of female external genitalia in a 46, XY human individual, with normally developed but undescended testes and complete unresponsiveness of target tissues to androgens. Subsequently, pelvic ultrasound or magnetic resonance imaging (MRI) could be helpful in confirming the absence of Mullerian structures, revealing the presence of a blind-ending vagina and identifying testes. CAIS management still represents a unique challenge throughout childhood and adolescence, particularly regarding timing of gonadectomy, type of hormonal therapy, and psychological concerns. Indeed this condition is associated with an increased risk of testicular germ cell tumour (TGCT), although TGCT results less frequently than in other disorders of sex development (DSD). Furthermore, the majority of detected tumoral lesions are non-invasive and with a low probability of progression into aggressive forms. Therefore, histological, epidemiological, and prognostic features of testicular cancer in CAIS allow postponing of the gonadectomy until after pubertal age in order to guarantee the initial spontaneous pubertal development and avoid the necessity of hormonal replacement therapy (HRT) induction. However, HRT is necessary after gonadectomy in order to prevent symptoms of hypoestrogenism and to maintain secondary sexual features. This article presents differential clinical presentations and management in patients with CAIS to emphasize the continued importance of standardizing the clinical and surgical approach to this disorder.

Severe forms of complete androgen insensitivity syndrome caused by a p.Q65X novel mutation in androgen receptor: Clinical manifestations, imaging findings and molecular genetics

Androgen insensitivity syndrome (AIS), a rare X-linked recessive genetic disorder with a normal 46, XY karyotype, is caused by defect of androgen receptor gene (AR) leading to resistance of the target tissues to androgenic hormones. There is a wide spectrum of clinical presentations of AIS, ranging from male infertility, hypospadias to completely normal female external genitalia. Here, we describe a 15-year old, phenotypically female individual, who visited our clinic for primary amenorrhea. The physical examination revealed normal female external genitalia, normal breast development, as well as sparse pubic hair and absence of axillary hair. A short blind vagina pouch was noticed in gynecological examination apart from the absence of cervix and uterus. Serum testosterone measured a considerable high level, and the karyotype was indicative of a normal male (46, XY). Transabdominal ultrasound (US) and magnetic resonance imaging (MRI) confirmed the absence of uterus, ovaries and fallopian tubes, only with a small blind-ending vagina observed. The clinical, laboratory, imaging, and genetic findings strongly suggest the diagnosis of complete androgen insensitivity syndrome (CAIS). Mutational analysis of the AR gene revealed a novel small insertion mutation c.192_193insTAGCAG(Q65X) in exon 1, which gives rise to a truncated nonfunctional protein, resulting in the loss of the remaining 856 C-terminus amino acid residues. This study indicates that US and MRI are two useful and noninvasive imaging methods for the diagnosis and evaluation of CAIS, and identification of this novel mutation expands the database of AR gene mutations. Furthermore, with the availability of the identification technology for this mutation, prenatal diagnosis could be offered for future pregnancies.

Management of Gonads in Adults with Androgen Insensitivity: An International Survey

BACKGROUND

Complete and partial androgen insensitivity syndrome (CAIS, PAIS) are associated with an increased risk of gonadal germ cell cancer (GGCC). Recent guidelines recommend gonadectomy in women with CAIS in late adolescence. Nevertheless, many adult women prefer to retain their gonads.

AIMS

This study aims to explore attitudes towards gonadectomy in AIS in centres around the world, estimate the proportion of adults with retained gonads and/or who developed GGCC, and explore reasons for declining gonadectomy.

METHODS

A survey was performed among health care professionals who use the International DSD Registry (I-DSD).

RESULTS

Data were provided from 22 centres in 16 countries on 166 women (CAIS) and 26 men (PAIS). In CAIS, gonadectomy was recommended in early adulthood in 67% of centres; 19/166 (11.4%) women refused gonadectomy. Among 142 women who had gonadectomy, evidence of germ cell neoplasm in situ (GCNIS), the precursor of GGCC, was reported in 2 (1.4%) out of 8 from whom pathology results were formally provided. Nine out of 26 men with PAIS (34.6%) had retained gonads; 11% of centres recommended routine gonadectomy in PAIS.

CONCLUSION

Although development of GGCC seems rare, gonadectomy after puberty is broadly recommended in CAIS; in PAIS this is more variable. Overall, our data reflect the need for evidence-based guidelines regarding prophylactic gonadectomy in AIS.

Malignant testicular germ cell tumors in postpubertal individuals with androgen insensitivity: prevalence, pathology and relevance of single nucleotide polymorphism-based susceptibility profiling

STUDY QUESTION

What is the prevalence of malignant testicular germ cell tumors (TGCT) and its precursors, (pre-) germ cell neoplasia in situ (GCNIS), in late teenagers and adults who have androgen insensitivity syndrome (AIS) and the impact of an individual's genetic susceptibility to development of TGCT?

SUMMARY ANSWER

No GCNIS or TGCT was diagnosed, but pre-GCNIS was identified in 14 and 10% of complete and partial AIS patients, respectively, and was associated with a higher genetic susceptibility score (GSS), with special attention for KITLG (rs995030) and ATFZIP (rs2900333).

WHAT IS KNOWN ALREADY

Many adult women with AIS decline prophylactic gonadectomy, while data regarding the incidence, pathophysiology and outcomes of TGCT in postpubertal individuals with AIS are lacking. The relevance of genetic factors, such as single nucleotide polymorphisms (SNPs), in predisposing AIS individuals to TGCT is unknown.

STUDY DESIGN, SIZE, DURATION

This multicenter collaborative study on prophylactically removed gonadal tissue was conducted in a pathology lab specialized in germ cell tumor biology.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Material from 52 postpubertal individuals with molecularly confirmed AIS (97 gonadal samples) was included; the median age at surgery was 17.5 (14-54) years. Immunohistochemical studies and high-throughput profiling of 14 TGCT-associated SNPs were performed. The main outcome measures were the prevalence of pre-GCNIS, GCNIS and TGCT, and its correlation with a GSS, developed based on the results of recent genome-wide association studies.

MAIN RESULTS AND ROLE OF CHANCE

The earliest recognizable change preceding GCNIS, referred to as pre-GCNIS, was present in 14% of individuals with complete and 10% of those with partial AIS at a median age of 16 years. No GCNIS or invasive TGCT were found. The median GSS was significantly greater for those with, compared to those without, pre-GCNIS (P = 0.01), with an overlap between groups. Our data suggest important roles for risk alleles G at KITLG (rs995030) and C at ATFZIP (rs2900333), among the 14 studied TGCT-associated SNPs.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

A limited number of cases were included.

WIDER IMPLICATIONS OF THE FINDINGS

Our data suggest that the prevalence of pre-GCNIS in individuals with AIS beyond puberty is around 15%. Genetic susceptibility likely contributes to pre-GCNIS development in AIS but factors related to malignant progression remain unclear. Although data in older patients remain scarce, malignant progression appears to be a rare event, although the natural history of the premalignant lesion remains unknown. Therefore, the practice of routine prophylactic gonadectomy in adults with AIS appears questionable and the patient's preference, after having been fully informed, should be decisive in this matter.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the Research Foundation Flanders (FWO) (to M.C.), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq G0D6713N) (to B.B.M. and M.C.) and the European Society for Pediatric Endocrinology (ESPE), granted by Novo Nordisk AB (to J.K.). There are no competing interests.

An immunohistochemical analysis of the effects of androgen receptor knock out on gubernacular differentiation in the mouse

AIM

Cryptorchidism affects 2%-4% of newborn boys and causes infertility and cancer. While normal androgen function is required for successful inguinoscrotal descent, its exact role on gubernacular morphology remains unidentified. We aimed to decipher the effect of androgen blockade on the gubernaculum and surrounding structures.

METHODS

Genetically modified mice with androgen receptor knock out (ARKO) were sectioned at ages E17, D0, and D2 for immunohistochemical analysis and D4 for morphological analysis (with ethical approval; A644). Mutants and control littermates were labeled with Ki67, Desmin, and Pax7 to identify the degree of gubernaculuar eversion and the composition of the growth center in the gubernaculum, using light or confocal microscopy.

RESULTS

Androgen blockade prevented gubernacular eversion in all animals aged between E17 and D2 when compared to wild types. Furthermore, a growth center was visible, as indicated by a 'swirl' of immature fibroblasts, in D2 animals but was absent in ARKO mice. Moreover, the gubernacular cord was seen to increase in ARKO mice when compared to wild types and increased in size with age. There were no labeling differences in the antibodies tested for gubernacular differentiation.

CONCLUSION

Gubernacular eversion in rodents prior to inguinoscrotal migration was androgen dependent, as well as maintenance of gubernacular cord length. This study shows that androgen blockade causes cryptorchidism in mice by preventing gubernacular eversion and possibly by preventing shortening of the gubernacular cord. Altering the morphology of the gubernaculum in response to androgen clearly contributes to the clinical problem of cryptorchidism.

Functional and Structural Study of the Amino Acid Substitution in a Novel Familial Androgen Receptor Mutation (W752G) Responsible for Complete Androgen Insensitivity Syndrome

Mutations of the androgen receptor (AR) gene are the most frequent cause of 46,XY disorders of sex development. They are associated with a variety of phenotypes, ranging from phenotypic women (complete androgen insensitivity syndrome, CAIS) to milder degrees of undervirilization (partial forms) or men with only infertility (mild form). We identified a new W752G AR mutation responsible for a familial case of CAIS and performed an in vitro study and structural analysis of this mutation and the only other reported substitution affecting the same amino acid (W752R). Although sex assignment is not discussed in cases of CAIS, we show how the phenotype-genotype correlation can be refined by in vitro and structural studies according to the nature of the amino acid substitution, which in turn may have interesting impacts on the follow-up of these patients.

Androgen Insensitivity Syndrome at Prepuberty: Marked Loss of Spermatogonial Cells at Early Childhood and Presence of Gonocytes up to Puberty

Androgen insensitivity syndrome (AIS) is a hereditary condition in patients with a 46,XY karyotype in which loss-of-function mutations of the androgen receptor (AR) gene are responsible for defects in virilization. The aim of this study was to investigate the consequences of the lack of AR activity on germ cell survival and the degree of testicular development reached by these patients by analyzing gonadal tissue from patients with AIS prior to Sertoli cell maturation at puberty. Twenty-three gonads from 13 patients with AIS were assessed and compared to 18 testes from 17 subjects without endocrine disorders. The study of the gonadal structure using conventional microscopy and the ultrastructural characteristics of remnant germ cells using electron microscopy, combined with the immunohistochemical analysis of specific germ cell markers (MAGE-A4 for premeiotic germ cells and of OCT3/4 for gonocytes), enabled us to carry out a thorough investigation of germ cell life in an androgen-insensitive microenvironment throughout prepuberty until young adulthood. Here, we show that germ cell degeneration starts very early, with a marked decrease in number after only 2 years of life, and we demonstrate the permanence of gonocytes in AIS testis samples until puberty, describing 2 different populations. Additionally, our results provide further evidence for the importance of AR signaling in peritubular myoid cells during prepuberty to maintain Sertoli and spermatogonial cell health and survival.

Frequency of gonadal tumours in complete androgen insensitivity syndrome (CAIS): A retrospective case-series analysis

BACKGROUND

Complete androgen insensitivity syndrome (CAIS) is an X-linked recessive disorder of sex development (DSD) where affected individuals are phenotypically female, but have an XY karyotype and testes. The risk of gonadal tumour development in CAIS may increase with age; incidence rates have been reported to be 0.8-22% in patients who have retained their gonads into adulthood. Consequently, gonadectomy has been recommended either during childhood or after puberty is complete, although there is no consensus on the optimal timing for this procedure.

OBJECTIVE AND HYPOTHESES

To establish the frequency of histological abnormalities in CAIS in relation to the age at gonadectomy.

METHOD

Data were collected from the Cambridge DSD database on patients with CAIS (n = 225; age range 3-88 years) who had undergone gonadectomy, and their age of gonadectomy, gonadal histology and immunohistochemistry.

RESULTS

Evaluable data were obtained from 133 patients. Median age at gonadectomy was 14.0 years (range: 18 days-68 years). Pubertal status was: prepuberty, n = 62; postpuberty, n = 68. Thirteen cases were aged >20 years at gonadectomy. The pattern of histology is summarised in the Summary table.

DISCUSSION

In this large case series of CAIS patients who had undergone gonadectomy, while the combined malignant and premalignant gonadal histology prevalence was 6.0%, the findings confirm the low occurrence of gonadal malignancy in CAIS, with a frequency of 1.5%. The two cases of malignancy were postpubertal. Germ cell neoplasia in situ (GCNIS) was observed in six cases, of which one occurred prepuberty and five postpuberty. The study highlighted difficulties in diagnosis of GCNIS and the need for histological analysis in expert centres.

CONCLUSION

The results support the current recommendation that gonads in CAIS can be retained until early adulthood. The small number of individuals with gonadectomy after age 20 years do not allow firm conclusion regarding later adulthood. Therefore, it is recommended that the option of gonadectomy be discussed in adulthood. Some form of regular surveillance of the gonads is then recommended, although none of the available options are ideal.

Testicular growth and development in puberty

PURPOSE OF REVIEW

To describe pubertal testicular growth in humans, changes in testicular cell populations that result in testicular growth, and the role of testosterone and gonadotrophins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in testicular growth. When human data were not available, studies in nonhuman primates and/or rodents were used as surrogates.

RECENT FINDINGS

Testicular growth in puberty follows a sigmoidal growth curve, with a large variation in timing of testicular growth and adult testicular volume. Testicular growth early in puberty is due to increase in Sertoli cell number and length of seminiferous tubules, whereas the largest and fastest growth results from the increase in the diameter of the seminiferous tubules first due to spermatogonial proliferation and then due to the expansion of meiotic and haploid germ cells. FSH stimulates Sertoli cell and spermatogonial proliferation, whereas LH/testosterone is mandatory to complete spermatogenesis. However, FSH and LH/testosterone work in synergy and are both needed for normal spermatogenesis.

SUMMARY

Testicular growth during puberty is rapid, and mostly due to germ cell expansion and growth in seminiferous tubule diameter triggered by androgens. Pre-treatment with FSH before the induction of puberty may improve the treatment of hypogonadotropic hypogonadism, but remains to be proven.

Malignancy in disorders of sex development

Disorders of sex development (DSD) represent a spectrum of conditions in which chromosomal, gonadal, or anatomic sex are atypical and affect 1 in 4,500-5,000 live births. The diagnosis of DSD raises concerns of tumor risk and treatment as well as future fertility preservation. We review the current understanding of the types of gonadal tumors that arise in DSD patients as well as possible markers and treatment. The goal is to inform the members of the DSD team (urologist, endocrinologist, geneticist, psychologist) of the latest findings regarding malignancy in DSD. PubMed^® and Google Scholar^TM literature searches were performed of current and past peer-reviewed literature on DSD (intersex) regarding gonadal development and tumor formation/treatment. Relevant reviews and original research articles were examined, including cited references, and a synopsis of the data was generated. DSD patients are at increased risk for the development of testicular carcinoma in-situ (CIS) and germ cell tumors (GCT), including seminoma, non-seminoma, juvenile granulosa cell, gonadoblastoma, and dysgerminoma. Cancer risk factors include Y-chromosomal material and gonadal position, especially for streak gonads. The 46 XX DSD patients [congenital adrenal hyperplasia (CAH)] with no genetic Y-chromosomal material are not at higher risk of cancer. Post-pubertal complete androgen insensitivity syndrome (AIS) patients remain prone to tumor development if the testes remain in the abdomen. Estimates of the risk of GCT in partial AIS for untreated undescended testes may be as high as 50%. The cancer risk of scrotal testes in partial AIS is unknown. CIS occurs almost exclusively in patients with hypovirilization, most notably in AIS. Persistent Mullerian Duct Syndrome (PMDS) confers the usual cancer risk associated with cryptorchidism, but also a possible tumor risk of the Mullerian remnant. Several markers are under investigation for tumor evaluation in the DSD population beyond hCG and AFP (Oct3/4, TSPY, WT-1). The management of patients with DSD is complex and evaluation of tumor risk is aided by advances in genotyping for Y-chromosomal material not evident in traditional karyotyping. More complete genetic screening for DSD patients should increasingly become the standard of care. Developments in pathologic diagnosis will further challenge our traditional understanding of the oncologic management and surveillance of these patients. Future studies utilizing more advanced histologic examination of gonads will improve our understanding of the true incidences of malignancy in this diverse population.

Laparoscopic approach for gonadectomy in pediatric patients with intersex disorders

The birth of a child with a disorder of sex development (DSD) prompts a long-term management strategy that involves a myriad of professionals working with the family. There has been progress in diagnosis, surgical techniques and in understanding psychosocial issues related to this condition. However, since these kinds of disorders are rare and have many anatomical variations, individual care is necessary, especially regarding surgical management. Gonadectomy is indicated in a number of intersex disorders with a Y chromosome to reduce the associated risk of cancer. Recently, laparoscopy has gained wide acceptance in pediatric urology. Laparoscopy is also reported to be a useful tool for diagnosing and treating DSD because of its minimal invasiveness and favorable cosmetic outcome. However, reports of evaluation and management using laparoscopy for large numbers of DSD patients are limited and debate is still open about indications and timing of gonadectomy. In this study, we reviewed the literature of the last 10 years about the role of laparoscopic gonadectomy in patients with DSD. In the analyzed papers, all the procedures were accomplished successfully using laparoscopy. No conversions to open surgery neither intra-operative complications were reported in all series. Post-operative complications were reported only in one series and included 1 umbilical port infection [2% (1/50)] and 1 pelvic abscess [2% (1/50)], both treated with antibiotic therapy (grade I Clavien-Dindo). Of the analyzed series, 7/10 reported postoperative diagnosis of gonadal tumors. The histopathologic examinations revealed 15 cases of gonadoblastoma, 7 cases of dysgerminoma and 2 cases of seminoma. Analyzing the single series, the incidence of these tumors varied between 10% and 33%. The results of our review confirmed the safety and efficacy of laparoscopic gonadectomy in DSD patients. In our mind, laparoscopic gonadectomy should be accepted as the treatment of choice in children and adolescents with these rare conditions. It thereby eliminates the risk of malignancies of gonadal origin with the advantages of a minimally invasive procedure, with lower morbidity, quicker postoperative recovery and excellent cosmetic results.

Timing of Gonadectomy in Patients with Complete Androgen Insensitivity Syndrome-Current Recommendations and Future Directions

This review highlights the controversy regarding timing of gonadectomy in patients with complete androgen insensitivity syndrome (CAIS). We will review the published literature regarding frequency of gonadal malignancy and summarize historical findings. Recent research suggests that gonadectomy may be deferred until adulthood due to the low risk of malignancy. An algorithm is also provided to help guide clinicians in management of patients with complete androgen insensitivity syndrome who have deferred gonadectomy.