Gonadal pathology and tumor risk in relation to clinical characteristics in patients with 45,X/46,XY mosaicism

Prenatal and postnatal evaluation of differences of sex development: a user's guide for clinicians and families

PURPOSE OF REVIEW

Differences of sex development (DSD) are a group of chromosomal, gonadal, and anatomic conditions that are not often diagnosed during pregnancy. Families and clinicians need diagnostic guidance that supports all aspects of the care from the prenatal to postnatal period.

RECENT FINDINGS

Noninvasive prenatal screening (NIPS) is obtained by sampling cell-free fetal DNA in the mother's bloodstream in the first trimester. While its primary purpose is to screen for genetic aneuploidies, it is also used to determine the sex of the fetus. When screening ultrasound shows genital anatomy that is discordant with the sex determination by NIPS, a DSD workup is warranted. The use of this relatively new screening tool may result in a higher number of prenatal referrals than in the past.

SUMMARY

This review summarizes suggested prenatal counseling, neonatal management, and postnatal workup of the most common DSD diagnoses. All of these diagnoses are rare, but the common features that families face are addressed with particular emphasis on psychosocial support and a measured shared decision-making approach.

Complex genomic rearrangements of the Y chromosome in a premature infant

BACKGROUND

Chromoanagenesis is an umbrella term used to describe catastrophic "all at once" cellular events leading to the chaotic reconstruction of chromosomes. It is characterized by numerous rearrangements involving a small number of chromosomes/loci, copy number gains in combination with deletions, reconstruction of chromosomal fragments with improper order/orientation, and preserved heterozygosity in copy number neutral regions. Chromoanagesis is frequently described in association with cancer; however, it has also been described in the germline. The clinical features associated with constitutional chromoanagenesis are typically due to copy number changes and/or disruption of genes or regulatory regions.

CASE PRESENTATION

We present an 8-year-old male patient with complex rearrangements of the Y chromosome including a ring Y chromosome, a derivative Y;21 chromosome, and a complex rearranged Y chromosome. These chromosomes were characterized by G-banded chromosome analysis, SNP microarray, interphase FISH, and metaphase FISH. The mechanism(s) by which these rearrangements occurred is unclear; however, it is evocative of chromoanagenesis.

CONCLUSION

This case is a novel example of suspected germline chromoanagenesis leading to large copy number changes that are well-tolerated, possibly because only the sex chromosomes are affected.

SRY-positive 45,X/46,XY karyotype in a phenotypically Turner-like Chinese adolescent female with ovarian dysgerminoma and gonadoblastoma

OBJECTIVES

45,X/46,XY mosaicism is a rare condition with clinical and genetic heterogeneity and have a greatly increased risk of developing germ cell tumors. We describe a rare 45,X/46,XY Chinese girl with malignant tumors, especially focusing on the molecular genetics of gonadal tumor.

CASE PRESENTATION

We report a phenotypically Turner-like Chinese adolescent girl who presented primary amenorrhea and a pelvic mass as the chief complaint, which finally demonstrated dysgerminoma replacing the left gonad and gonadoblastoma arising from right gonad respectively. Her chromosome karyotype was 45,X(4)/46,XY(46); Y-chromosome microdeletions in AZFb regions were found on gonadal DNA rather than peripheral blood lymphocyte (PBL) DNA, while no variants were found in the promoter and coding region of SRY gene in both PBL and gonadal tissues. She underwent bilateral gonadectomy; no recurrence or serious complications were identified after 3 years of follow-up.

CONCLUSIONS

This case emphasizes the probable correlation between Y chromosome microdeletions in gonadal tissue and the severity of the phenotype in patients with 45,X/46,XY mosaicism and highlights the importance of clinical genetic testing at the chromosomal and molecular level.

45,X/46,XY mosaicism: Clinical manifestations and long term follow-up

45,X/46,XY chromosomal mosaicism presents a range of clinical manifestations, including phenotypes from Turner syndrome through genital abnormalities to apparently unaffected phenotypic males; however, the full clinical spectrum has not yet been fully delineated since prior studies on the clinical phenotype and associated risk of gonadal tumors included small cohorts and limited follow-up. To better describe the clinical manifestations and long-term outcome of patients with 45,X/46,XY mosaicism. We conducted a retrospective chart review of patients with 45,X/46,XY from three health centers (Hospital for Sick Children and Mount Sinai Hospital in Canada, and University of Pittsburgh Medical Center in United States). Of 100 patients with 45,X/46,XY karyotype, 47 were raised as females and 53 as males. Females were significantly shorter than males (p = 0.04) and height Z-score was significantly decreased with age for both genders (p = 0.02). Growth hormone (GH) treatment did not result in a significant height increase compared to the untreated group (p = 0.5). All females required puberty induction in contrast to majority of males. Five females were diagnosed with gonadal tumors, while no males were affected. Around 58% of patients exhibited at least one Turner syndrome stigmata. This study expands the clinical spectrum, long-term outcomes, and associated tumor risk in a large cohort of patients with 45,X/46,XY mosaicism. Additionally, it highlights our experience with GH therapy and prophylactic gonadectomy.

Rare Case of a Turner Syndrome Patient with Metastatic Dysgerminoma and No Y-Chromosomal Material with Pathogenic Variants Found in KIT and MTOR

INTRODUCTION

The presence of Y-chromosomal material in females with Turner syndrome (TS) is a well-established risk factor for developing gonadoblastoma and malignant transformations thereof. However, these events are rarely seen in TS patients with no Y-chromosomal material. Thus, it is the current understanding that parts of the Y-chromosome are essential for the malignant transformation of gonadoblastoma in the dysgenetic gonad.

METHODS

We report a case of a TS female with an apparent 46,X,idic(Xq) karyotype, who was diagnosed with a metastatic dysgerminoma. Whole exome sequencing of the tumor and blood, along with RNA sequencing of the tumor, was performed to comprehensively search for cryptic Y-chromosomal material and pathogenic variants.

RESULTS

No Y-chromosomal material was detected in either tumor or blood. Whole exome-sequencing of DNA and RNA revealed a pathogenic somatic gain-of-function mutation in KIT and a pathogenic missense mutation in MTOR. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy, followed by adjuvant chemotherapy. Unfortunately, she died due to chemotherapy-induced pneumonitis 7 months after the initial diagnosis.

CONCLUSION

Females with TS can develop metastatic dysgerminoma even in the absence of Y-chromosomal material. This questions the current understanding of Y-chromosomal material being essential for the malignant transformation of a gonadoblastoma in the dysgenetic gonad.

Etiology, histology, and long-term outcome of bilateral testicular regression: a large Belgian series

STUDY QUESTION

What is the long-term outcome of individuals born with bilateral testicular regression (BTR) in relation to its underlying etiology?

SUMMARY ANSWER

Statural growth and pubertal development are adequate with incremental doses of testosterone replacement therapy (TRT); however, penile growth is often suboptimal, especially in those with a suspected genetic etiology (i.e. heterozygous DHX37 variants) or a micropenis at birth.

WHAT IS KNOWN ALREADY

BTR is a rare and poorly understood condition. Although a vascular origin has been postulated, heterozygous missense variants in DHX37 have been attributed to the phenotype as well. How these various etiologies impact the clinical phenotype, gonadal histology and outcome of BTR remains unclear.

STUDY DESIGN SIZE DURATION

For this cross-sectional study, individuals with BTR were recruited in eight Belgian pediatric endocrinology departments, between December 2019 and December 2022. A physical exam was performed cross-sectionally in all 17 end-pubertal participants and a quality of care questionnaire was completed by 11 of them. Exome-based panel testing of 241 genes involved in gonadal development and spermatogenesis was performed along with a retrospective analysis of presentation and management. A centralized histological review of gonadal rests was done for 10 participants.

PARTICIPANTS/MATERIALS SETTING METHODS

A total of 35 participants (33 with male, 1 with female, and 1 with non-binary gender identity) were recruited at a mean age of 15.0 ± 5.7 years.

MAIN RESULTS AND THE ROLE OF CHANCE

The median age at presentation was 1.2 years [0-14 years]. Maternal gestational complications were common (38.2%), with a notably high incidence of monozygotic twin pregnancies (8.8%). Heterozygous (likely) pathogenic missense variants in DHX37 (p.Arg334Trp and p.Arg308Gln) were found in three participants. No other (likely) pathogenic variants were found. All three participants with a DHX37 variant had a microphallus at birth (leading to female sex assignment in one), while only six of the remaining 31 participants without a DHX37 variant (19.4%) had a microphallus at birth (information regarding one participant was missing). Testosterone therapy during infancy to increase penile growth was more effective in those without versus those with a DHX37 variant. The three participants with a DHX37 variant developed a male, female, and non-binary gender identity, respectively; all other participants identified as males. TRT in incremental doses had been initiated in 25 participants (median age at start was 12.4 years). Final height was within the target height range in all end-pubertal participants; however, 5 out of 11 participants (45.5%), for whom stretched penile length (SPL) was measured, had a micropenis (mean adult SPL: 9.6 ± 2.5). Of the 11 participants who completed the questionnaire, five (45.5%) reported suboptimal understanding of the goals and effects of TRT at the time of puberty induction. Furthermore, only 6 (54.5%) and 5 (45.5%) of these 11 participants indicated that they were well informed about the risks and potential side effects of TRT, respectively. Histological analysis of two participants with DHX37 variants suggested early disruption of gonadal development due to the presence of Müllerian remnants in both and undifferentiated gonadal tissue in one. In eight other analyzed participants, no gonadal remnants were found, in line with the BTR diagnosis.

LIMITATIONS REASONS FOR CAUTION

The limitations of this study include the relatively small sample size (n = 35) and the few individuals with DHX37 variants (n = 3). Furthermore, data on the SPL were often missing, due to this being undocumented or refused by participants.

WIDER IMPLICATIONS OF THE FINDINGS

TRT provides adequate statural growth, even when initiated in late adolescence, thus providing time for physicians to explore the patients' gender identity if needed. However, sufficient and understandable information regarding the effects and side effects of TRT is required throughout the management of these patients. SPL remains suboptimal in many individuals and could be improved by TRT during infancy to mimic the physiological mini-puberty. An environmental origin in some participants is supported by the high incidence of gestational complications (38.2%) and by the three monozygotic twin pregnancies discordant for the BTR phenotype. Individuals with a heterozygous DHX37 variant have a more severe phenotype with severely restricted penile growth until adulthood. Histological analysis confirmed DHX37 as a gonadal development, rather than a BTR-related, gene.

STUDY FUNDING/COMPETING INTERESTS

Funding was provided by the Belgian Society for Pediatric Endocrinology and Diabetology (BESPEED) and by Ghent University Hospital under the NucleUZ Grant (E.D.B.). M.C. and E.D.B. are supported by an FWO senior clinical investigator grant (1801018N and 1802220N, respectively). The authors report no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Prevalence, distribution, and risk markers for the development of gonadal germ cell tumors in patients with certain types of disorders of sexual differentiation with Y chromosome - A retrospective study

PURPOSE

To study the prevalence, subtypes, and risk markers for the development of gonadal germ cell tumors (GCT's) among disorders of sexual differentiation (DSD) patients with the Y chromosome.

MATERIALS AND METHOD

Design: A retrospective review of the patient's case records from 2010 to 2020 in Government Medical College, Thiruvananthapuram, India was studied. The study participants included 54 subjects with DSD containing the Y chromosome. Demographic data, external masculinization scoring, associated congenital anomalies, karyotyping, intraoperative findings such as gonadal location and internal genital ducts, histopathology of the resected gonads, and its immunohistochemistry were collected. The prevalence of gonadal GCT's was estimated from paraffin-embedded gonadectomy samples (S = 82).

RESULTS

The median age of occurrence of gonadal GCT's was 18 years. The prevalence of malignant gonadal GCT's was highest among the PAIS group (19.2%) followed by gonadal dysgenesis (15.8% each in MGD and CGD) and least among CAIS (7.7%) (p < 0.01). The most common type of malignant gonadal GCT's in the descending order of frequency was dysgerminoma, seminoma, mixed GCT, and yolk sac tumor. Multivariance logistic analysis showed post-puberty and the presence of congenital anomalies were associated with the occurrence of gonadal GCT's ( P < 0.01).

CONCLUSION

The overall prevalence of gonadal GCT's (malignant and premalignant) among DSD with Y chromosomes is nearly 25%. Dysgerminoma is the most common malignant gonadal GCT's. Age at or above 18 years and the presence of congenital anomalies like renal agenesis, retroperitoneal vascular defects, and congenital diaphragmatic hernia were independent risk markers for the development of gonadal GCT's.

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.

Individuals with numerical and structural variations of sex chromosomes: interdisciplinary management with focus on fertility potential

Diagnosis and management of individuals who have differences of sex development (DSD) due to numerical or structural variations of sex chromosomes (NSVSC) remains challenging. Girls who have Turner syndrome (45X) may present with varying phenotypic features, from classical/severe to minor, and some remain undiagnosed. Boys and girls who have 45,X/46,XY chromosomal mosaicism may have Turner syndrome-like features and short stature; therefore, unexplained short stature during childhood requires karyotype analysis in both sexes, particularly if characteristic features or atypical genitalia are present. Many individuals with Klinefelter syndrome (47XXY) remain undiagnosed or are only diagnosed as adults due to fertility problems. Newborn screening by heel prick tests could potentially identify sex chromosome variations but would have ethical and financial implications, and in-depth cost-benefit analyses are needed before nationwide screening can be introduced. Most individuals who have NSVSC have lifelong co-morbidities and healthcare should be holistic, personalized and centralized, with a focus on information, psychosocial support and shared decision-making. Fertility potential should be assessed individually and discussed at an appropriate age. Oocyte or ovarian tissue cryopreservation is possible in some women who have Turner syndrome and live births have been reported following assisted reproductive technology (ART). Testicular sperm cell extraction (TESE) is possible in some men who have 45,X/46,XY mosaicism, but there is no established protocol and no reported fathering of children. Some men with Klinefelter syndrome can now father a child following TESE and ART, with multiple reports of healthy live births. Children who have NSVSC, their parents and DSD team members need to address possibilities and ethical questions relating to potential fertility preservation, with guidelines and international studies still needed.

A rare case of mixed gonadal dysgenesis in adulthood: diagnostic delay and unique outcomes

Mixed gonadal dysgenesis (MGD) is a rare sex development disorder, diagnosed by mosaic karyotype of 45,X/46,XY (classical form) with the presence of Müllerian structures, unilateral testis and contralateral streak gonad. MGD expresses diverse phenotypes, from female phenotype with virilization or turner stigmata, to ambiguous genitalia or male phenotype. Early diagnosis is crucial for effective correction of height, sexual development and cancer prevention. The study reports on a case of a 25-year-old patient, reared as female, presenting a large abdominal mass later confirmed as a mixed germ cell tumor. Associated findings were primary amenorrhea, ambiguous genitalia, short statue, gender dysphoria and hyperlipidemia. The study is the first to report on hyperlipidemia in MGD.

Genetic control of typical and atypical sex development

Sex development relies on the sex-specific action of gene networks to differentiate the bipotential gonads of the growing fetus into testis or ovaries, followed by the differentiation of internal and external genitalia depending on the presence or absence of hormones. Differences in sex development (DSD) arise from congenital alterations during any of these processes, and are classified depending on sex chromosomal constitution as sex chromosome DSD, 46,XY DSD or 46,XX DSD. Understanding the genetics and embryology of typical and atypical sex development is essential for diagnosing, treating and managing DSD. Advances have been made in understanding the genetic causes of DSD over the past 10 years, especially for 46,XY DSD. Additional information is required to better understand ovarian and female development and to identify further genetic causes of 46,XX DSD, besides congenital adrenal hyperplasia. Ongoing research is focused on the discovery of further genes related to typical and atypical sex development and, therefore, on improving diagnosis of DSD.

Differences of sexual development: genetic counseling considerations in the prenatal setting

PURPOSE OF REVIEW

With the rapid adoption of noninvasive prenatal screening (NIPS), predictive fetal sex information is available early in pregnancy. This information can conflict with the results of other prenatal tests such as fetal ultrasound or diagnostic testing and raise the possibility of a fetal difference of sexual development (DSD). In this review, we describe recent studies examining the counseling and outcomes of prenatally suspected DSD.

RECENT FINDINGS

Discordance in prenatal genetic testing results can cause confusion and anxiety in families as expectations of testing are not often discussed in detail prior to testing. There are no established guidelines for the counseling or management of such situations.

SUMMARY

We present case vignettes to highlight relevant counseling points and considerations to aid in the development of guidelines and best practices in the management of DSD in the prenatal setting.

Clinical and hormonal characteristics and growth data of 45,X/46,XY mosaicism in 38 Chinese patients

Backgrounds

45,X/46,XY mosaicism is the most common type of sex chromosomal abnormality in disorders of sex development (DSD). We investigated the clinical manifestations, serum sex hormone levels and growth data of 38 45,X/46,XY mosaicism patients, which provides better insight into this disease.

Methods

We prospectively evaluated 38 patients who were diagnosed with 45,X/46,XY mosaicism at the Department of Endocrinology of Shanghai Children's Hospital from 2010 to 2020. We analyzed clinical data from the patients, including hormone levels, height, weight, body mass index (BMI) and gonadal pathology results.

Results

Among the 38 cases of 45,X/46,XY mosaicism, 18 cases showed a female external genitalia phenotype (the female group) with an external masculinization score (EMS) of 1 (0-3) [median (range)], and 20 cases showed a male external genitalia phenotype (the male group) with an EMS of 7.63 (3-11) [median (range)]. The age at diagnosis ranged from 0.7 to 16.1 years. Under 2 years of age, the standard deviation scores of height (HtSDS) were in the normal range and then they gradually decreased. The inhibin B (INHB), anti-Mullerian hormone (AMH), and testosterone (T) levels after human chorionic gonadotropin (HCG) stimulation and the T:DHT ratio in the male group were significantly higher than those in the female group (P < 0.001). The basal luteinizing hormone (LH), basal follicle-stimulating hormone (FSH), peak LH and peak FSH in females were significantly higher than those in males (P < 0.05). Their height showed a positive correlation with T levels after HCG stimulation (r = 0.636, P < 0.01), T:DHT ratio (r = 0.724, P < 0.01), growth hormone (GH) (r = 0.827, P < 0.05), and insulin-like growth factor 1 (IGF-1) (r = 0.067, P > 0.05) and a negative correlation with gonadal pathology in ovarian tissue (r = -0.663, P < 0.05) and the number of chimaeric XY cells (r = -0.533, P < 0.05).

Conclusions

Patients with 45,X/46,XY mosaicism have specific growth patterns. Their HtSDS was in the normal range during 0-2 years of age and then they began to show a short stature after 2 years of age. The probability of short stature in females was higher than that in males. WtSDS were all in the normal range, but below the median. BMISDS was in the normal range, and there was no evidence of obesity. The gonads in the male group retained a certain androgen secretion function, while the gonadal damage is more severe in the female group.

Prevalence and characteristics of gonadoblastoma in a retrospective multi-center study with follow-up investigations of 70 patients with Turner syndrome and a 45,X/46,XY karyotype

INTRODUCTION

A gonadectomy is currently recommended in patients with Turner syndrome (TS) and a 45,X/46,XY karyotype, due to a potential risk of gonadoblastoma (GB). However, the quality of evidence behind this recommendation is low.

OBJECTIVE

This study aimed to evaluate the prevalence of GB, its characteristics, as well as its risk factors, according to the type of Y chromosomal material in the karyotype.

METHODS

Our study within French rare disease centers included patients with TS and a 45,X/46,XY karyotype, without ambiguity of external genitalia. Clinical characteristics of the patients, their age at gonadectomy, and gonadal histology were recorded. The regions of the Y chromosome, the presence of TSPY regions, and the percentage of 45,X/46,XY mosaicism were evaluated.

RESULTS

A total of 70 patients were recruited, with a median age of 29.5 years (21.0-36.0) at the end of follow-up. Fifty-eight patients had a gonadectomy, at a mean age of 15 ± 8 years. GB was present in nine cases. Two were malignant, which were discovered at the age of 14 and 32 years, without metastases. Neither the percentage of XY cells within the 45,X/46,XY mosaicism nor the number of TSPY copies was statistically different in patients with or without GB (P = 0.37). However, the entire Y chromosome was frequent in patients with GB (6/9).

CONCLUSIONS

In our study, including a large number of patients with 45,X/46,XY TS, the prevalence of gonadoblastoma is 12.8%. An entire Y chromosome appears as the main risk factor of GB and should favor early gonadectomy.

SIGNIFICANT STATEMENT

About 10% of patients with TS have a karyotype containing Y chromosomal material: 45,X/46,XY. Its presence is related to the risk of GB. Therefore, a prophylactic gonadectomy is currently recommended in such patients. However, the quality of evidence is low. Our objective was to evaluate the prevalence of GB according to the type of Y-chromosomal material. We found a prevalence of GB of 12.8% in a cohort of 70 TS patients. No sign of hyperandrogenism was observed. The entire Y chromosome was the most frequent type of Y-material in patients with GB. As the prognosis of these tumors was good, a delay of surgery might be discussed.

Consensus guide on prophylactic gonadectomy in different sex development

The risk of suffering from gonadal germ cell tumors (GCT) is increased in some patients with different sexual development (DSD), mainly in those with Y chromosome material. This risk, however, varies considerably depending on a multitude of factors that make the decision for prophylactic gonadectomy extremely difficult. In order to make informed recommendations on the convenience of this procedure in cases where there is potential for malignancy, this consensus guide evaluates the latest clinical evidence, which is generally low, and updates the existing knowledge in this field.

Adnexal Torsion Due to Borderline Mucinous Tumor of the Gonad in a Prepubertal Girl with Mixed Gonadal Dysgenesis (45,X/46,XY) and a Turner Phenotype

BACKGROUND

Turner syndrome (TS) is a sex chromosome condition characterized by complete or partial loss of the X chromosome. Patients with mixed gonadal dysgenesis (45,X/46,XY) and a Turner phenotype are predisposed to gonadoblastoma with malignant transformation.

CASE

We present the case of a TS patient with 45,X/46,XY with 2 episodes of left adnexal torsion (AT). Biopsies during detorsion showed benign mucinous cystadenoma. Pathology following bilateral gonadectomy revealed a left gonad with mucinous borderline tumor and right gonad with gonadoblastoma, both of which have malignant potential.

SUMMARY AND CONCLUSION

Gonadectomy is recommended in XY gonadal dysgenesis to decrease risk of malignant transformation from gonadoblastoma. Although rare in pediatric patients, ovarian malignancies have been identified among AT cases. To our knowledge, we present the first case of AT due to borderline ovarian mucinous tumor of the ovary and contralateral gonadoblastoma in a patient with mixed gonadal dysgenesis (45,X/46,XY) and a Turner phenotype.

Surgery in Chinese children affected by 45,X/46,XY disorders of sex development: A 20-year experience in a single center

BACKGROUND

Children affected by 45,X/46,XY mosaicism have a wide spectrum in their phenotypes. Although surgery has a role in management, there is no universally agreed strategy.

METHODS

We conducted a retrospective review in a tertiary center on the surgical management and its long-term outcomes in children with the karyotype 45,X/46,XY or its variants over a 20-year study period. Patients were divided into 4 groups based on their phenotypes.

RESULTS

22 children(female=13, male=9) were included in the study, and were grouped as I)female phenotype(n = 11), II)ambiguous external genitalia(n = 2), III)undervirilized male with hypospadias(n = 6), and IV)normal male phenotype(n = 3). 19/22(86%) underwent gonadal surgeries(bilateral gonadectomy=15; unilateral gonadectomy=1; testicular biopsy=3) and  8/22(36%) underwent genitalia reconstructive surgeries(hypospadias repair=6; feminizing surgery=2). Gonadal germ cell tumors were detected in 55%, 50% and 50% of Group I, II and III respectively. 3/6 patients required reoperations for complications after hypospadias repairs. None of the patients had recurrence of germ cell tumors after gonadectomy. All the patients who had reached late adolescence or adulthood maintained their genders as their sex of rearing.

CONCLUSIONS

Majority of 45,X/46,XY children benefit from timely gonadal surgery while genitalia reconstructive surgery can be considered in selected patients. Surgical management can be strategized by patients' phenotypes.

Sex chromosome DSD individuals with mosaic 45,X0 and aberrant Y chromosomes in 46,XY cells: distinct gender phenotypes and germ cell tumour risks§

"Differences of Sexual Development (DSD)," individuals with rearranged Y chromosome breaks in their 46,XY cells are reported with male and female gender phenotypes and differences in germ cell tumour (GCT) risk. This raised the question of whether male or female gender and GCT risk depends on the site of the break and/or rearrangement of the individual´s Y chromosome. In this paper, we report molecular mapping of the breakpoint on the aberrant Y chromosome of 22 DSD individuals with a 45,X/46,XY karyotype reared with a different gender. Their Y chromosome breaks are found at different sites on the long and short Y arms. Our data indicate that gender rearing is, neither dependent on the site of Y breakage, nor on the amount of 45,X0 cells in the individuals' leukocytes. Most prominent are secondary rearrangements of the Y chromosome breaks forming di-centric Y-structures ("dic-Y"). Duplications of the short Y arm and the proximal part of the long Y arm are the results. A putative GCT risk has been analysed with immunohistochemical experiments on some dysgenetic gonadal tissue sections. With specific antibodies for OCT3/4 expression, we marked the pluripotent germ cell fraction being potential tumour precursor cells. With specific antibodies for DDX3Y, TSPY, and UTY we analyzed their putative Gonadoblastoma Y (GBY) tumour susceptibility function in the same specimen. We conclude GBY expression is only diagnostic for GCT development in the aberrant germ cells of these DSD individuals when strong OCT3/4 expression has marked their pluripotency.

Neoplasia in Turner syndrome: a retrospective cohort study in a tertiary referral centre in Belgium

OBJECTIVES

Patients with Turner syndrome (TS), the most common sex chromosome abnormality in women, can suffer from a variety of well-researched reproductive, cardiovascular, metabolic, and autoimmune comorbidities. Few studies investigate the neoplasia risk. We assessed the general neoplasia risk in TS women, and more specifically, the gonadoblastoma/dysgerminoma risk in the subgroup with Y chromosome mosaicism, and evaluated potential risk factors for neoplasia development, such as karyotype, metabolic and autoimmune comorbidity, and treatment with growth hormone and/or estrogen replacement.

DESIGN

10-year retrospective cohort study in a tertiary referral centre in Belgium.

RESULTS

105 TS women were included (median age 29; range 2-69). Six malignant tumours were detected in 5 (4.8%) patients (SIR = 0.6, 95% CI 0.2-1.0). In addition, 2 benign meningiomas were observed, resulting in 3 (2.9%) tumours of the central nervous system (CNS; SIR = 19.9, 95% CI 4.0-35.8). No breast cancer was noted. Benign neoplasms occurred in 22 women (21.0%), with skin lesions being the most frequent. All patients with Y chromosome mosaicism (n = 9; 8.6%) underwent prophylactic gonadectomy, but gonadoblastoma/dysgerminoma was not detected. A weak association was found between any tumour type and autoimmune comorbidity (r = 0.24; p = 0.02).

CONCLUSION

The overall malignancy risk was not increased, but a different pattern of occurrence is apparent, with an increased risk of CNS and skin tumours and a decreased breast cancer risk. Gonadoblastoma/dysgerminoma was not reported. There is a need for centralised multidisciplinary care and prospective research to unravel and predict the neoplasia risk.

Case Report: Genetic Analysis of a Small Supernumerary Marker Chromosome in a Unique Case of Mosaic Turner Syndrome

BACKGROUND

The aim of this study was to explore the source and morphology of a small supernumerary marker chromosome (sSMC) from karyotype analysis of a patient with a unique case of mosaic Turner syndrome. The study findings will provide technical reference and genetic counseling for similar cases.

CASE PRESENTATION

A female patient with 46,X,+mar karyotype was diagnosed by genetic karyotype analysis. Genetic methods including fluorescence in situ hybridization (FISH) and copy number variation sequencing (CNV-seq) based on low-depth whole-genome sequencing were used to explore the source and morphology of sSMC. FISH technology showed that 56.5% of the cells were X and 43.5% of the cells were XY. CNV-seq detection found that the sSMC was chrY, implying that the patient's karyotype was mos 45,X[58.6%]/46,XY[41.4%]. Retrospective karyotype analysis indicated that the female patient's sSMC was inherited from her father's small chrY. Customized FISH probe of Yq12 microdeletion was positive, indicating that the sSMC was a del(Y)(q12). Based on the results of genetic diagnosis, the specialist doctor gave a comprehensive genetic consultation and ordered regular follow-up examinations.

CONCLUSIONS

The findings of the current study showed that the chromosome description of the unique Turner case was mos 45,X[56.5%]/46,X,del(Y)(q12)[43.5%]. FISH technology played a key role in diagnosis of mosaicism. The terminal deletion of mosaic chrY provided a scientific and an accurate explanation for masculinity failure and abnormal sexual development of the current case.

Gonadal tumor and malignancy in 118 patients with disorders of sex development with Y chromosome

OBJECTIVE

To provide more information about tumor prevalence and malignant transformation among patients with disorders of sex development (DSD) for further guidance in prophylactic gonadectomies and surveillance.

METHODS

SPSS software (version 20.0) was used for all statistical analyses.

RESULTS

Phenotypically female DSD patients with a Y chromosome have a higher risk of gonadal malignancy.

CONCLUSION

Bilateral gonadal resection is recommended as soon as diagnosis is made for phenotypically female patients with disorders of sex development with a Y chromosome.

Clinical and Reproductive Characteristics of Patients with Mixed Gonadal Dysgenesis (45,X/46, XY)

Introduction

Mixed gonadal dysgenesis (MGD) or 45,X/46,XY mosaicism is a sex chromosomal disorder of sexual development. We aim to characterize the clinical and reproductive features of 45X/46 XY attending tertiary care center in Kerala.

Materials and Method

Retrospective review of clinical records which include clinical presentation, hormonal profile, cytogenetics, psychosexual assessment, and histopathology of gonadectomy specimen of ten cases of 45X/46 XY mosaicism who attended Endocrinology/ OBG out patient department from 2008 to 2020.

Results

The mean ages of all the cases were 12 ± 3.79 years (± 2 SD). Short stature was universally seen. Virilisation was the most common manifestation (80%) followed by delayed puberty (20%). Autoimmune thyroid disease was seen in 40% of cases. We noticed a delayed presentation in our clinical study. 45X/46 XY subjects who wished to continue as female underwent gonadectomy and were feminized with hormone replacement therapy. Male 45X/46 XY who retained their undescended testis is planned for periodic surveillance for malignancy.

Conclusion

45X/46 XY may present like Turner's syndrome in clinical practice. Early counseling and gender assignment by a panel of specialists are crucial. Delayed presentation is less commonly encountered now a day and may pose a clinical challenge. Management in 45X/46 XY is multi-disciplinary which includes Turner's like surveillance, proper sex assignment, timely genital reconstruction surgeries, gonadectomy, gonadal monitoring, and hormonal replacement therapy is needed.

Can Boys Have Turner Syndrome? More than a Question of Semantics

Individuals with 45,X mosaicism with Y chromosome material raised as boys are not diagnosed with Turner syndrome, a label restricted to phenotypic females. We sought to determine if boys with 45,X mosaicism had features consistent with Turner syndrome. Twenty-two patients (14 girls, 8 boys) seen in our Differences of Sex Development (DSD) clinic were identified for review. Standardized height (z-scores) by sex of rearing and results of cardiology, renal, audiology, thyroid, and celiac screenings were recorded. All subjects had heights below the mean for sex. Z-scores were not significantly different between boys and girls (p = 0.185). There were no significant differences in the incidence of cardiac anomalies between boys and girls (p = 0.08). Girls were more likely to have additional screenings (p = 0.042), but there were no significant differences in the number of positive screenings between boys and girls (p = 0.332). Patients with 45,X mosaicism raised as boys appear to have features similar to patients with the same karyotype raised as girls. Routine screening of boys following the Turner Syndrome Clinical Practice Guidelines may allow early recognition of comorbidities. Additionally, obtaining karyotypes on boys with short stature or other features of Turner syndrome may identify unrecognized cases of 45,X mosaicism.

Role of minimally invasive surgery (MIS) in different sexual development (DSD)

Differences/disorders of sex development (DSD) are a heterogeneous group of congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical. Patients usually present during the newborn period but occasionally some cases remain unrecognized until later in infancy or even adolescence. Genital appearance, psychosocial support, sociocultural background, gender identity development, and genetic and biochemical analysis in addition to ethical and legal implications need to be considered when deciding on the appropriate treatment strategy. Surgeons are important members of the multidisciplinary expert teams involved in the initial approach and long-term follow-up. Surgical care of DSD patients is one of the main challenges. Recommendations regarding the opportunity and timing of surgical procedures are still under discussion. Surgical procedures are aimed to reduce urologic problems, prevent the risk of gonadal germ-cell cancer, and facilitate sexual function and reproduction. Providing its excellent visualization, access to pelvic structures and less postoperative adhesion MIS has been an important tool in the diagnosis and treatment of DSD. The role of MIS will be summarized in: 1) Gonadal biopsy / gonadectomy 2) Treatment of urogenital sinus/vaginoplasty 3) Vaginal Replacement 4) Resection / treatment of Mullerian structures.

Growth and relationship of phenotypic characteristics with gonadal pathology and tumour risk in patients with 45, X/46, XY mosaicism

OBJECTIVE

To evaluate the growth data, gonadal functions and tumour risk in children with 45, X/46, XY mosaicism.

DESIGN

We reviewed retrospectively the records of 45 patients with 45, X/46, XY mosaicism or variants presented to our Unit from 1989 to 2019.

RESULTS

The age at diagnosis ranged from 0.03 to 17.5 years. Twenty-eight patients had genital anomaly, 14 patients had female external genitalia and 3 patients had normal male genitalia. Patients showed normal height under 2 years of age. Mean height standard deviation score (HSDS) of 19 patients diagnosed before 2 years of age was -0.9 ± 0.6 and that of 26 patients diagnosed after 2 years of age was -2.6 ± 1.5. Ten patients diagnosed before 2 years of age showed growth deceleration after 2 years of age (HSDS decreasing from -0.6 ± 0.7 to -1.4 ± 0.9). Twenty-one patients reached adult height (AH). Growth hormone (GH) treatment was initiated in 10 patients. Although AHSDS of GH-treated patients was significantly greater than their mean HSDS before GH therapy (p =.013), it was not significantly different from AHSDS of the untreated group. Seventeen (37.8%) patients exhibited phenotypical features of Turner syndrome (TS) other than short stature. Two patients with genital anomaly had gonadoblastoma and germ cell neoplasia in situ, and one patient with female external genitalia had gonadoblastoma.

CONCLUSIONS

GH therapy seems to improve AH of patients. Both patients with genital anomaly and female external genitalia have increased risk of germ cell tumours.

Sex attribution, gender identity and quality of life in disorders of sex development due to 45,X/46,XY mosaicism: methods for clinical and psychosocial assessment

The choice of sex in newborns with genital ambiguity is challenging. Information concerning the satisfaction of subjects with disorders of sex development from childhood to adulthood is required in order to address sex attribution policies. This study focuses on the methods that enable clinicians to investigate the alignment of phenotypes with gender identity and quality of life in people with disorders of this kind. These methods are presented as tools for studying a cohort of ten subjects with 45,X/46,XY mosaicism examined between 1985 and 2014 in the Department of Pediatric Endocrinology, Regina Margherita Children's Hospital, Turin: five children and five young adults, four reared as females and six as males. Clinical outcome was assessed by means of a clinical scoring system considering height, genital appearance, gonads and pubertal development. The Gender Identity Questionnaire for Children and the World Health Organization Quality of Life assessment were adopted. The four male children strongly identified with their assigned sex: male attribution was satisfactory until pubertal age. In young adults the clinical scores ranged between 55–65% for both genders. In the young male, the reduced sexual activity and the poor body image perception strongly affected his quality of life. The clinical scores of the two young female adults (60% for both) were not balanced with their quality of life scores (87.5% and 68.75% respectively): individual traits and social-familial context should be investigated in order to explain these differences. Clinical and psychosocial assessment in people with disorders of sex development is mandatory in order to plan care procedures; a detailed analysis requires adequate tools. Clinical scoring system, Gender Identity Questionnaire for Children and World Health Organization Quality of Life assessment can be used to investigate the alignment of physical phenotype with gender identity and quality of life.

Can the external masculinization score predict the success of genetic testing in 46,XY DSD?

Genetic testing is judiciously applied to individuals with Disorders of Sex Development (DSD) and so it is necessary to identify those most likely to benefit from such testing. We hypothesized that the external masculinization score (EMS) is inversely associated with the likelihood of finding a pathogenic genetic variant. Patients with 46,XY DSD from a single institution evaluated from 1994–2014 were included. Results of advanced cytogenetic and gene sequencing tests were recorded. An EMS score (range 0–12) was assigned to each patient according to the team's initial external genitalia physical examination. During 1994–2011, 44 (40%) patients with 46,XY DSD were evaluated and underwent genetic testing beyond initial karyotype; 23% (10/44) had a genetic diagnosis made by gene sequencing or array. The median EMS score of those with an identified pathogenic variant was significantly different from those in whom no confirmed genetic cause was identified [median 3 (95% CI, 2–6) versus 6 (95% CI, 5–7), respectively (p = 0.02)], but limited to diagnoses of complete or partial androgen insensitivity (8/10) or 5α-reductase deficiency (2/10). In the modern cohort (2012–2014), the difference in median EMS in whom a genetic cause was or was not identified approached significance (p = 0.05, median 3 (95% CI, 0–7) versus 7 (95% CI, 6–9), respectively). When all patients from 1994–2014 are pooled, the EMS is significantly different amongst those with compared to those without a genetic cause (median EMS 3 vs. 6, p < 0.02). We conclude that an EMS of 3 or less may indicate a higher likelihood of identifying a genetic cause of 46,XY DSD and justify genetic screening, especially when androgen insensitivity is suspected.

Mosaic Turner Syndrome With 45,X/46,XY Mosaicism and Apparent Absent Uterus

Turner syndrome (TS) is a relatively common chromosomal abnormality in females. Short stature, gonadal dysgenesis, and somatic dysmorphic features are the characteristic features of the syndrome. The chromosomal abnormalities of TS are highly variable; 45,X/46,XY mosaicism accounts for 10-12% of cases of Turner syndrome. Despite the presence of hypogonadism, affected females typically have a uterus. Here, we report the case of a 22-year-old female who presented at 15 years of age with primary amenorrhea. She was diagnosed with Turner syndrome mosaicism with a karyotype of 45,X/46,XY. Her pelvic imaging showed an absent uterus and ovaries. Due to the presence of a Y chromosome, she underwent prophylactic gonadectomy. Histopathology of her removed gonads confirmed the diagnosis of mixed gonadal disorder. She was started on estrogen replacement. Four years after treatment, she developed her menses. Her repeated pelvic magnetic resonance imaging showed the presence of a small uterus.

Approach to the Virilizing Girl at Puberty

Virilization is the medical term for describing a female who develops characteristics associated with male hormones (androgens) at any age, or when a newborn girl shows signs of prenatal male hormone exposure at birth. In girls, androgen levels are low during pregnancy and childhood. A first physiologic rise of adrenal androgens is observed at the age of 6 to 8 years and reflects functional activation of the zona reticularis of the adrenal cortex at adrenarche, manifesting clinically with first pubic and axillary hairs. Early adrenarche is known as "premature adrenarche." It is mostly idiopathic and of uncertain pathologic relevance but requires the exclusion of other causes of androgen excess (eg, nonclassic congenital adrenal hyperplasia) that might exacerbate clinically into virilization. The second modest physiologic increase of circulating androgens occurs then during pubertal development, which reflects the activation of ovarian steroidogenesis contributing to the peripheral androgen pool. However, at puberty initiation (and beyond), ovarian steroidogenesis is normally devoted to estrogen production for the development of secondary female bodily characteristics (eg, breast development). Serum total testosterone in a young adult woman is therefore about 10- to 20-fold lower than in a young man, whereas midcycle estradiol is about 10- to 20-fold higher. But if androgen production starts too early, progresses rapidly, and in marked excess (usually more than 3 to 5 times above normal), females will manifest with signs of virilization such as masculine habitus, deepening of the voice, severe acne, excessive facial and (male typical) body hair, clitoromegaly, and increased muscle development. Several medical conditions may cause virilization in girls and women, including androgen-producing tumors of the ovaries or adrenal cortex, (non)classical congenital adrenal hyperplasia and, more rarely, other disorders (also referred to as differences) of sex development (DSD). The purpose of this article is to describe the clinical approach to the girl with virilization at puberty, focusing on diagnostic challenges. The review is written from the perspective of the case of an 11.5-year-old girl who was referred to our clinic for progressive, rapid onset clitoromegaly, and was then diagnosed with a complex genetic form of DSD that led to abnormal testosterone production from a dysgenetic gonad at onset of puberty. Her genetic workup revealed a unique translocation of an abnormal duplicated Y-chromosome to a deleted chromosome 9, including the Doublesex and Mab-3 Related Transcription factor 1 (DMRT1) gene.

LEARNING OBJECTIVES

Identify the precise pathophysiologic mechanisms leading to virilization in girls at puberty considering that virilization at puberty may be the first manifestation of an endocrine active tumor or a disorder/difference of sex development (DSD) that remained undiagnosed before and may be life-threatening. Of the DSDs, nonclassical congenital adrenal hyperplasia occurs most often.Provide a step-by-step diagnostic workup plan including repeated and expanded biochemical and genetic tests to solve complex cases.Manage clinical care of a girl virilizing at puberty using an interdisciplinary team approach.Care for complex cases of DSD manifesting at puberty, such as the presented girl with a Turner syndrome-like phenotype and virilization resulting from a complex genetic variation.

Underrepresentation of Phenotypic Variability of 16p13.11 Microduplication Syndrome Assessed With an Online Self-Phenotyping Tool (Phenotypr): Cohort Study

Background

16p13.11 microduplication syndrome has a variable presentation and is characterized primarily by neurodevelopmental and physical phenotypes resulting from copy number variation at chromosome 16p13.11. Given its variability, there may be features that have not yet been reported. The goal of this study was to use a patient “self-phenotyping” survey to collect data directly from patients to further characterize the phenotypes of 16p13.11 microduplication syndrome.

Objective

This study aimed to (1) discover self-identified phenotypes in 16p13.11 microduplication syndrome that have been underrepresented in the scientific literature and (2) demonstrate that self-phenotyping tools are valuable sources of data for the medical and scientific communities.

Methods

As part of a large study to compare and evaluate patient self-phenotyping surveys, an online survey tool, Phenotypr, was developed for patients with rare disorders to self-report phenotypes. Participants with 16p13.11 microduplication syndrome were recruited through the Boston Children's Hospital 16p13.11 Registry. Either the caregiver, parent, or legal guardian of an affected child or the affected person (if aged 18 years or above) completed the survey. Results were securely transferred to a Research Electronic Data Capture database and aggregated for analysis.

Results

A total of 19 participants enrolled in the study. Notably, among the 19 participants, aggression and anxiety were mentioned by 3 (16%) and 4 (21%) participants, respectively, which is an increase over the numbers in previously published literature. Additionally, among the 19 participants, 3 (16%) had asthma and 2 (11%) had other immunological disorders, both of which have not been previously described in the syndrome.

Conclusions

Several phenotypes might be underrepresented in the previous 16p13.11 microduplication literature, and new possible phenotypes have been identified. Whenever possible, patients should continue to be referenced as a source of complete phenotyping data on their condition. Self-phenotyping may lead to a better understanding of the prevalence of phenotypes in genetic disorders and may identify previously unreported phenotypes.

Clinical phenotype and management of individuals with mosaic monosomy X with Y chromosome material stratified by genital phenotype

Individuals mosaic for monosomy X and a cell line with Y chromosome material can have genitalia that appear phenotypical female, male, or ambiguous. Those with this karyotype and typical female genitalia are diagnosed with Turner syndrome; however, this definition specifically excludes those with genitalia other than typical female. There is limited information on whether medical and neurodevelopmental risks are similar among individuals with monosomy X and Y chromosome material across genital phenotypes. This multicenter retrospective study compared comorbidities and clinical management in individuals with monosomy X and Y material and male/ambiguous genitalia to those with typical female genitalia. Electronic medical records for all patients with monosomy X and Y material (n = 76) at two large U.S. pediatric centers were abstracted for predetermined data and outcomes. Logistic regression was used to compare the two phenotypic groups adjusting for site and duration of follow-up. The male/ambiguous genitalia group was just as likely to have congenital heart disease (RR 1.0, 95%CI [0.5-1.9]), autoimmune disease (RR 0.6 [0.2-1.3]), and neurodevelopmental disorders (RR 1.4 [0.8-1.2]) as those with female genitalia. Despite similar risks, they were less likely to receive screening and counseling. In conclusion, individuals with monosomy X and Y chromosome material have similar medical and neurodevelopmental risks relative to individuals with Turner syndrome regardless of genitalia, but there are notable differences in clinical management.

Multidisciplinary Approach to the Child with Sex Chromosomal Mosaicism Including a Y-Containing Cell Line

Children born with sex chromosomal mosaicism including material derived from the Y chromosome may present with a broad phenotypical spectrum. Both boys and girls can present with Turner features and functional health problems typically associated with Turner syndrome, but the presence of Y-chromosomal material can modify some aspects of the condition. We retrospectively analyzed the results of our cohort of 21 individuals (14 boys, 7 girls) with sex chromosomal mosaicism including Y-derived material followed at Ghent University Hospital according to our local multidisciplinary Turner surveillance protocol. Results were compared with literature data, focusing on similarities and differences between girls and boys with this condition. Age at diagnosis was lower in boys compared to girls but the difference was not significant. Short stature is a key feature of the condition both in girls and boys, but skeletal maturation may be different between groups. The effects of growth-hormone therapy remain unclear. Cardiac (33%), ear-nose- throat (ENT) (77.8%) and renal (28.6%) problems were as prevalent in boys as in girls from our cohort, and did not differ from literature data. In line with literature reports, a significant difference in the presence of premalignant germ cell tumors between males (0%) and females (42.9%) was found (p = 0.026). Taken together, this study demonstrates the similarities between girls with Turner syndrome and children with sex chromosomal mosaicism including Y-derived material, regardless of the child’s gender. Nowadays, girls with Turner syndrome are offered a dedicated multidisciplinary follow-up in many centers. We advocate a similar follow-up program for all children who have sex chromosomal mosaicism that includes Y-derived material, with special attention to growth, cardiac and ear-nose-throat problems, gonadal function and malignancies.

45,X/46,XY Mosaicism in an 18-year-old Girl with Primary Amenorrhea : A Case Report

45,X/46,XY mosaicism is a rare disorder with a wide heterogeneity in its manifestations. An 18-year-old girl was referred to the endocrine clinic for investigation of her primary amenorrhea. Clinical examination was unremarkable. Hormonal profile was consistent with primary ovarian insufficiency and human chorionic gonadotropin (hCG) stimulation did not show evidence of active testicular tissue. Karyotyping studies by G-banding revealed a 45,X/46,XY karyotype. She was diagnosed with mosaic Turner syndrome with Y chromosomal material and investigation was performed to identify the presence of male gonads due to the risk of gonadal malignancy. Magnetic resonance imaging (MRI) of the pelvis did not show evidence of gonads. Laparoscopic exploration was proposed but the patient and parents refused opting for conservative management. This case highlights the challenges in the management of this rare condition.

Serum Concentrations and Gonadal Expression of INSL3 in Eighteen Males With 45,X/46,XY Mosaicism

OBJECTIVE

Insulin-like factor 3 (INSL3) is produced in the testes and has been proposed as a circulating biomarker of Leydig cell capacity, but remains undescribed in 45,X/46,XY mosaicism. The aim was to examine serum concentrations and gonadal expression of INSL3 in 45,X/46,XY mosaicism.

METHODS

Retrospectively collected data from medical records, gonadal tissue samples, and prospectively analyzed serum samples from eighteen male patients with 45,X/46,XY mosaicism (one prepubertal, four testosterone-treated, 13 untreated) were included. Biochemical, clinical, and histological outcomes were evaluated according to serum INSL3 concentrations, quantified by LC-MS/MS methodology, and gonadal INSL3 immunohistochemical expression.

RESULTS

Serum INSL3 concentrations spanned from below to above the reference range. In untreated patients, the median serum INSL3 SD score was -0.80 (IQR: -1.65 to 0.55) and no significant difference was observed between INSL3 and testosterone. There was no clear association between serum INSL3 and External Genitalia Score at diagnosis, spontaneous puberty, or sperm concentration. INSL3 and CYP11A1 expression overlapped, except for less pronounced INSL3 expression in areas with severe Leydig cell hyperplasia. No other apparent links between INSL3 expression and histological outcomes were observed.

CONCLUSIONS

In this pilot study, serum INSL3 concentrations ranged and seemed independent of other reproductive hormones and clinical features in males with 45,X/46,XY mosaicism. Discordant expression of INSL3 and CYP11A1 may explain low INSL3 and normal testosterone concentrations in some patients. Further studies are needed to elucidate the divergence between serum INSL3 and testosterone and the potential clinical use of INSL3.

Diagnosis and treatment of the intra-abdominal gonad in the pediatric population: Testes, ovaries, dysgenetic gonads, streaks, and ovotestes

BACKGROUND/PURPOSE

Pediatric surgical specialists are often confronted with the difficult task of identifying, diagnosing and managing intra-abdominal gonads in children. Ranging from the intra-abdominal cryptorchid testis to normal or pathologic ovaries and gonads in disorders of sexual development, all intra-abdominal gonads in the pediatric population pose different diagnosis and management challenges. Understanding the hormonal and fertility potential of the gonad and knowing its potential cancer risk is essential when deciding how to manage these patients. In addition, the ideal surgical management for each one of these patients is often debated.

METHODS

Descriptive literature review.

RESULTS/CONCLUSION

Herein, we reviewed gonadal formation, common etiologies, diagnosis and management of intra-abdominal testes, pathologic ovaries and gonads in disorders of sexual development. Fertility potential and cancer risk for each were also reviewed and how both affect surgical management of the gonad.

TYPE OF STUDY/LEVEL OF EVIDENCE

Review Article, Level V.

Diagnostic cytogenetic testing following positive noninvasive prenatal screening results of sex chromosome abnormalities: Report of five cases and systematic review of evidence

BACKGROUND

Follow-up cytogenetic analysis has been recommended for cases with positive noninvasive prenatal screening (NIPS) results. This study of five cases with numerical and structural sex chromosomal abnormalities (SCA) and a review of large case series of NIPS provided guidance to improve prenatal diagnosis for SCA.

METHODS

Following positive NIPS results for SCA, karyotype analysis, chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH), and locus-specific quantitative PCR were performed on cultured amniocytes, chorionic villi cells, and stimulated lymphocytes. Review of large case series was performed to evaluate the NIPS positive rate, follow-up rate of cytogenetic analysis, positive predictive value (PPV) for major types of SCA, and relative frequencies of subtypes of major SCA.

RESULTS

Of the five cases with positive NIPS for SCA, case 1 showed a mosaic pattern of monosomy X and isodicentric Y; case 2 showed a mosaic pattern of monosomy X confined to the placenta; cases 3 and 4 had an isochromosome of Xq, and case 5 showed a derivative chromosome 14 from a Yq/14p translocation of maternal origin. Review of literature showed that mean positive rate of NIPS for SCA was 0.61%, follow-up rate of cytogenetics analysis was 76%, and mean PPV for SCA was 48%. Mosaic patterns and structural rearrangements involving sex chromosomes were estimated in 3%-20% and 3% of SCA cases, respectively.

CONCLUSION

These five cases further demonstrated the necessity to pursue follow-up cytogenetic analysis to characterize mosaic patterns and structural abnormalities involving sex chromosomes and their value for prenatal genetic counseling. A workflow showing the performance of current NIPS and cytogenetic analysis for SCA was summarized. These results could facilitate an evidence-based approach to guide prenatal diagnosis of SCA.

The External Genitalia Score (EGS): A European Multicenter Validation Study

CONTEXT

Standardized description of external genitalia is needed in the assessment of children with atypical genitalia.

OBJECTIVES

To validate the External Genitalia Score (EGS), to present reference values for preterm and term babies up to 24 months and correlate obtained scores with anogenital distances (AGDs).

DESIGN, SETTING

A European multicenter (n = 8) validation study was conducted from July 2016 to July 2018.

PATIENTS AND METHODS

EGS is based on the external masculinization score but uses a gradual scale from female to male (range, 0-12) and terminology appropriate for both sexes. The reliability of EGS and AGDs was determined by the interclass correlation coefficient (ICC). Cross-sectional data were obtained in 686 term babies (0-24 months) and 181 preterm babies, and 111 babies with atypical genitalia.

RESULTS

The ICC of EGS in typical and atypical genitalia is excellent and good, respectively. Median EGS (10th to 90th centile) in males < 28 weeks gestation is 10 (8.6-11.5); in males 28-32 weeks 11.5 (9.2-12); in males 33-36 weeks 11.5 (10.5-12) and in full-term males 12 (10.5-12). In all female babies, EGS is 0 (0-0). The mean (SD) lower/upper AGD ratio (AGDl/u) is 0.45 (0.1), with significant difference between AGDl/u in males 0.49 (0.1) and females 0.39 (0.1) and intermediate values in differences of sex development (DSDs) 0.43 (0.1). The AGDl/u correlates with EGS in males with typical genitalia and in atypical genitalia.

CONCLUSIONS

EGS is a reliable and valid tool to describe external genitalia in premature and term babies up to 24 months. EGS correlates with AGDl/u in males. It facilitates standardized assessment, clinical decision-making and multicenter research.

High frequency of Y chromosome microdeletions in male infertility patients with 45,X/46,XY mosaicism

The mosaic 45,X/46,XY karyotype is a common sex chromosomal abnormality in infertile men. Males with this mosaic karyotype can benefit from assisted reproductive therapies, but the transmitted abnormalities contain 45,X aneuploidy as well as Y chromosome microdeletions. The aim of this study was to investigate the clinical and genetic characteristics of infertile men diagnosed with 45,X/46,XY mosaicism in China. Of the 734 infertile men found to carry chromosomal abnormalities, 14 patients were carriers of 45,X/46,XY mosaicism or its variants, giving a prevalence of 0.27% (14/5269) and accounting for 1.91% (14/734) of patients with a chromosomal abnormality. There were ten cases (71.43%, 10/14) of 45,X mosaicism exhibiting AZF microdeletions. Case 1 and Case 4 had AZFc deletions, and the other eight cases had AZFb+c deletions. A high frequency of Y chromosome microdeletions were detected in male patients with 45,X/46,XY mosaicism. Preimplantation genetic diagnosis should be offered to men having intracytoplasmic sperm injection for hypospermatogenesis caused by 45,X/46,XY mosaicism, to avoid the risk of transfering AZF microdeletions in addition to X monosomy in male offspring.

Turner Syndrome with Y Chromosome: Spontaneous Thelarche, Menarche, and Risk of Malignancy

STUDY OBJECTIVE

Girls with Turner syndrome with Y-chromosome material (TS + Y) are assumed to have nonfunctional gonads with increased tumor risk, therefore prophylactic gonadectomy is recommended at diagnosis. In this study we aimed to determine rates of spontaneous thelarche (ST) and spontaneous menarche (SM), and prevalence of gonadal tumor and malignancy in girls with TS + Y, to further inform discussions about gonadectomy.

DESIGN

Retrospective review of clinical and pathology data.

SETTING

Multicenter study involving 4 United States children's hospitals.

PARTICIPANTS

Patients included those with a genetically proven diagnosis of TS + Y and phenotypically female genitourinary exam.

INTERVENTIONS

Demographic characteristics, pubertal development, and gonadal pathology data were abstracted from clinical records. Data for ST were analyzed for patients aged 13 years and older and SM for patients older than 15 years.

MAIN OUTCOME MEASURES

ST, SM, prevalence of gonadal tumor, and malignancy.

RESULTS

Forty-four patients met inclusion criteria. Nineteen patients were 13 years or older; 8/19 (42%) had ST and reached Tanner stages 2-4 and 2 (11%) had normal ovarian pathology. Nineteen patients were 15 years or older; 2/19 (11%) had SM. Thirty-seven patients underwent gonadectomy; 35 had available pathology results. Gonadoblastoma was identified in 35/7 patients (19%), 1 in situ germ cell neoplasia, and 1 dysgerminoma (3%). One patient with bilateral gonadoblastoma had ST and SM.

CONCLUSION

In this multicenter cohort, 42% of girls with TS + Y entered puberty spontaneously and 11% had SM, supportive of gonadal function. Risk of tumor was similar to previous reports. To achieve informed decision-making, discussions about gonadectomy should incorporate potential for gonadal function and tumor risk.

Variation of Gonadal Dysgenesis and Tumor Risk in Patients With 45,X/46,XY Mosaicism

OBJECTIVE

To describe the gonadal features of patients with 45,X/46,XY mosaicism, and to evaluate the prevalence of gonadal tumor in different phenotypes.

MATERIALS AND METHODS

The medical records of consecutive patients with 45,X/46,XY karyotype or its variants who had undergone gonadal biopsy or gonadectomy at a single institute between 1996 and 2017 were retrospectively reviewed.

RESULTS

Of 34 patients with 45,X/46,XY mosaicism, a unilateral dysgenetic testis and a contralateral streak gonad was detected in 20 patients (59%), bilateral streak gonads in 9 (26%), and bilateral dysgenetic testes in 5 (15%). A gonad composed of both streak and dysgenetic testicular portions was observed in 7 gonads of 6 patients. All streak gonads were removed, and bilateral gonadectomy was performed in 15 patients raised as girls. Pathologic examination revealed gonadal tumors in 6 of the 34 (18%) patients, including a gonadoblastoma in 7 gonads among 5 patients and an association of dysgerminoma with gonadoblastoma in 1 gonad. All 6 patients who developed gonadal tumor had female genitalia. Postoperative course was uneventful except 1 boy. A seminoma was developed in his soritaly scrotal testis at the age of 16 years.

CONCLUSION

The prevalence of gonadal tumor in patients with 45,X/46,XY mosaicism may vary according to the phenotype, and high in patients with female phenotype. Considering the increased risk of gonadal tumors in such patients, early investigation and individual management, including prophylactic gonadectomy, are recommended. In male patients, a close follow-up of the preserved testes is mandatory until adulthood.

Clinical but Not Histological Outcomes in Males With 45,X/46,XY Mosaicism Vary Depending on Reason for Diagnosis

CONTEXT

Larger studies on outcomes in males with 45,X/46,XY mosaicism are rare.

OBJECTIVE

To compare health outcomes in males with 45,X/46,XY diagnosed as a result of either genital abnormalities at birth or nongenital reasons later in life.

DESIGN

A retrospective, multicenter study.

SETTING

Sixteen tertiary centers.

PATIENTS OR OTHER PARTICIPANTS

Sixty-three males older than 13 years with 45,X/46,XY mosaicism.

MAIN OUTCOME MEASURES

Health outcomes, such as genital phenotype, gonadal function, growth, comorbidities, fertility, and gonadal histology, including risk of neoplasia.

RESULTS

Thirty-five patients were in the genital group and 28 in the nongenital. Eighty percent of all patients experienced spontaneous pubertal onset, significantly more in the nongenital group (P = 0.023). Patients were significantly shorter in the genital group with median adult heights of 156.7 cm and 164.5 cm, respectively (P = 0.016). Twenty-seven percent of patients received recombinant human GH. Forty-four patients had gonadal histology evaluated. Germ cells were detected in 42%. Neoplasia in situ was found in five patients. Twenty-five percent had focal spermatogenesis, and another 25.0% had arrested spermatogenesis. Fourteen out of 17 (82%) with semen analyses were azoospermic; three had motile sperm.

CONCLUSION

Patients diagnosed as a result of genital abnormalities have poorer health outcomes than those diagnosed as a result of nongenital reasons. Most patients, however, have relatively good endocrine gonadal function, but most are also short statured. Patients have a risk of gonadal neoplasia, and most are azoospermic, but almost one-half of patients has germ cells present histologically and up to one-quarter has focal spermatogenesis, providing hope for fertility treatment options.

Clinical management in mixed gonadal dysgenesis with chromosomal mosaicism: Considerations in newborns and adolescents

Individuals born on the spectrum of genetic abnormalities known as mixed gonadal dysgenesis (MGD) have a wide range of anatomical findings and management can be challenging in the newborn and adolescent. Historically, many individuals with MGD have undergone gonadectomy to avert the risk of gonadal malignancy. However, gonadectomy deprives patients of the benefits of their endogenous hormones, potential fertility, and in the case with MGD, has historically been done prior to addressing gender identity. Some patient advocates have proposed a delayed approach to surgical reconstructions and/or gonadectomy in other differences/disorders of sex development (DSD), particularly in patients with congenital adrenal hyperplasia and androgen insensitivity syndrome. In many areas of the world, there continues to be a shift toward delayed reconstructions and hesitancy regarding irreversible gonadectomy. To date, no clinical management protocol addressing these issues from a patient-centered approach has been described. We review what is known about malignancy risk and propose a management protocol for those with MGD that involves shared decision making regarding the gonads and addresses the long-term challenges with regard to gender and anatomy.

Early Bilateral Gonadoblastoma Associated With 45,X/46,XY Mosaicism: The Spectrum of Undifferentiated Gonadal Tissue and Gonadoblastoma in the First Months of Life

45,X/46,XY mosaicism is one of a heterogenous group of congenital conditions known as differences (disorders) of sex development (DSD) that results in abnormal development of internal and external genitalia. Patients with DSD, particularly those with segments of the Y chromosome, are at increased risk for germ cell tumors including gonadoblastoma. Gonadoblastoma is a neoplasm comprised of a mixture of germ cells and elements resembling immature granulosa or Sertoli cells with or without Leydig cells or lutein-type cells in an ovarian type stroma. Gonadoblastoma has an increased prevalence of 15% to 40% in patients with 45,X/46,XY mosaicism and has been previously reported in patients as young as 5 months of age with that karyotype. Herein, we describe a 3-month-old child with 45,X/46,XY karyotype who was referred for the evaluation of asymmetric labia majora. Additional evaluation revealed left streak gonad and right dysplastic/dysgenetic testis. Both gonads contained foci of cells typical for gonadoblastoma as well as undifferentiated gonadal tissue, underscoring the potential for very early infantile gonadoblastoma and the spectrum of developmental anomalies associated with this karyotype.

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.

Growth data and tumour risk of 32 Chinese children and adolescents with 45,X/46,XY mosaicism

BACKGROUND

The aim of this study was to review the growth data, gonadal function and tumour risk of children and adolescents with 45,X/46,XY mosaicism who presented to a single centre in China.

METHODS

We conducted a retrospective review of the records of 32 patients with 45,X/46,XY mosaicism or variants who were hospitalized from August 2005 to September 2018. The main outcomes measured were growth data, genital phenotype, gonadal function, gonadal position, and histological results.

RESULTS

A total of 32 patients were included. The age at diagnosis ranged from 0.6 to 16.3 years. Nineteen patients exhibited ambiguous genitalia, 12 had short stature, and 1 showed a lack of breast development. Seventeen patients were raised as males, and 15 were raised as females. The external masculinisation score (EMS) of patients raised as male was 4.5 (1~12) [median (range)]. The EMS of the females was 0 (0~1.5) [median (range)]. Patients showed normal heights under 2 years old, with a height SDS of 0 (- 1.5~1.4) [median (range)]. Growth appeared to decelerate after age 2 years, with SDS decreased to - 2.8 (- 3.0~ - 0.9) [median (range)]. The percentage of short stature was higher in females than in males (76.9% vs 50.0%). Twenty-five patients had gonadal pathological results. Complete gonadal dysgenesis (CGD) and mixed gonadal dysgenesis (MGD) were the most common pathogenic subtypes, accounting for 48.0 and 36.0%, respectively. Ovotesticular tissue was observed in only 4.0% of patients. Gonadoblastoma and positive OCT3/4 results were found in 18.8% of gonads in children over 2 years of age. Palpable gonads accounted for 50% of these. All patients who had gonadoblastoma were raised as females.

CONCLUSIONS

Patients with 45,X/46,XY might have normal heights until 2 years old. Growth decelerations after 2 years of age were common. Patients who are being raised as females seemed to be shorter than males. CGD and MGD were the most common gonadal pathogenic subtypes. The tumour risk is high in these patients, even in palpable gonads and female patients.

Short Stature on a Boy: Mosaicism with an Isodicentric Y Chromosome

Mosaicism brings great variability into the clinical expression of numerical and structural chromosomal abnormalities. The phenotypic variability of 45,X/46,XY mosaicism extends from Turner syndrome to apparently physically normal males. We present a case of a 14-year-old adolescent with short stature and delayed puberty, who was admitted in a Paediatric Endocrinology outpatient clinic. After a careful investigation, he was found to have a 45,X/46,X,idic(Y)(p11.32) mosaicism. This case report emphasizes the wide range of etiologies that can be involved in short stature and that chromosomal study is an important tool when firstly approaching males with short stature, avoiding unnecessary tests. There is an important clinical need for gonadal follow-up in this situation and for support in the decision about sex of rearing and sex orientation, when justifiable.

[Atypical genital development and tumor risk]

Atypical genital development (AGD), also called disorders of sex development are a set of miscellaneous pathologies who have in common a morphological and/or functional abnormality of the internal and/or external genital organs. The Chicago classification identifies 3 major groups based on karyotype, hormone balance and genetic studies. Some AGD predispose to the occurrence of tumors, mainly malignant germ cell tumors. The tumor risk depends on many factors: the type of AGD, the position of the gonad, the age of the patient, the phenotype, the function of the gonad and the presence of germ cells in the gonad. AGD with the highest tumor risk are those with gonadal dysgenesis, implying an incomplete differentiation of the bipotential gonad (dysplasia). Monitoring of patients with AGD and indication of prophylactic gonadectomies should be individualized according to tumor risk.

The Dilemma of Sex of Rearing: A Case of a 45,X/46,XY Neonate with Hydrocolpos

BACKGROUND

A rare disorder of sex development is 45,X/46,XY mosaicism, which is phenotypically very heterogenous, ranging from normal male (or female) to that of genital ambiguity of varying degrees.

CASE

We report a case of a neonate with 45,X/46,XY mosaicism and hydrocolpos, and we point out the dilemma and the difficulty in gender assignment.

SUMMARY AND CONCLUSION

Gender assignment of cases with frank genital ambiguity is often difficult to be determined, because several factors have to be taken into consideration, such as genital appearance, anticipated urological and sexual function, capacity for future fertility, gonadal malignancy risk, and psychosocial factors. A multidisciplinary approach is definitely needed in the management of such cases.