Disorders of sex development: update on the genetic background, terminology and risk for the development of germ cell tumors

Pure 46, XY gonadal dysgenesis and 46, XY complete androgen insensitivity syndrome: A case report

BACKGROUND

Disorders of sex development (DSD) are congenital conditions characterized by atypical development of chromosomal, gonadal, and phenotypic sex. 46, XY DSD can result from disorders of testicular development or androgen synthesis.

METHODS

We present 2 rare cases of 46, XY DSD, specifically XY pure gonadal dysgenesis and complete androgen insensitivity syndrome.

RESULTS

Both cases underwent prophylactic gonadectomy due to the elevated risk of gonadal malignancy. Bilateral gonadoblastoma and dysgerminoma were diagnosed on one side, while Leydig cell hyperplasia and only Sertoli cells were diagnosed in the seminiferous tubules on both sides. The normal menstruation for the pure gonadal dysgenesis patient only as CAIS patients never menstruate. Estrogen replacement therapy was administered periodically to promote the development of secondary sexual characteristics and menstruation in pure gonadal dysgenesis case, as well as to prevent osteoporosis. Follow-up examinations revealed no tumor recurrence, and the patient with Swyer syndrome had regular menstrual cycles.

CONCLUSION

Laparoscopic bilateral prophylactic gonadectomy and long-term hormone therapy with patient counseling and support are recommended.

Adolescent and Young Adult Germ Cell Tumors: Epidemiology, Genomics, Treatment, and Survivorship

Innovations in the care of adolescent and young adult (AYA) germ cell tumors (GCTs) are needed for one of the most common AYA cancers for which treatment has not significantly changed for several decades. Testicular GCTs (TGCTs) are the most common cancers in 15- to 39-year-old men, and ovarian GCTs (OvGCTs) are the leading gynecologic malignancies in women younger than 25 years. Excellent outcomes, even in widely metastatic disease using cisplatin-based chemotherapy, can be achieved since Einhorn and Donohue's landmark 1977 study in TGCT. However, as the severity of accompanying late effects (ototoxicity, neurotoxicity, cardiovascular disease, second malignant neoplasms, nephrotoxicity, and others) has emerged, efforts to deintensity treatment and find alternatives to cisplatin have taken on new urgency. Current innovations include the collaborative design of clinical trials that accrue GCTs across all ages and both sexes, including adolescents (previously on pediatric trials), and OvGCT (previously on gynecologic-only trials). Joint trials accrue larger sample sizes at a faster rate and therefore evaluate new approaches more rapidly. These joint trials also allow for biospecimen collection to further probe GCT etiology and underlying mechanisms of tumor growth, thus providing new therapeutic options. This AYA approach has been fostered by The Malignant Germ Cell International Consortium, which includes over 115 GCT disease experts from pediatric, gynecologic, and genitourinary oncologies in 16 countries. Trials in development incorporate, to our knowledge, for the first time, molecular risk stratification and precision oncology approaches on the basis of specific GCT biology. This collaborative AYA approach pioneering successfully in GCT could serve as a model for impactful research for other AYA cancer types.

Workflow for Management of Gonadal Neoplasm in 2 Patients with Differences of Sex Development Enrolled in an Experimental Gonadal Tissue Cryopreservation Protocol

OBJECTIVE

To outline our experimental gonadal tissue cryopreservation (GTC) protocol that does not disrupt the standard of care in medically-indicated gonadectomy for patients with differences of sex development, including highlighting the multidisciplinary collaborative protocol for when neoplasm is discovered in these cases.

METHODS

Two patients with complete gonadal dysgenesis who were undergoing medically-indicated prophylactic bilateral gonadectomy elected to pursue GTC. Both were found to have germ cell neoplasia in situ on initial pathologic analysis, requiring recall of the gonadal tissue, which had been cryopreserved.

RESULTS

Cryopreserved gonadal tissue was successfully thawed and transferred to pathology for complete analysis. No germ cells were identified in either patient nor were found to have malignancy, so further treatment beyond gonadectomy was not indicated. Pathologic information was communicated to each family, including that long-term GTC was no longer possible.

CONCLUSION

Organizational planning and coordination between the clinical care teams, GTC laboratory, and pathology were key to handling these cases with neoplasia. Processes that anticipated the possibility of discovering neoplasia within tissue sent to pathology and the potential need to recall GTC tissue to complete staging included (1) documenting the orientation and anatomical position of tissue processed for GTC, (2) defining parameters in which tissue will be recalled, (3) efficiently thawing and transferring GTC tissue to pathology, and (4) coordinating release of pathology results with verbal communication from the clinician to provide context. GTC is desired by many families and at the time of gonadectomy and is (1) feasible for patients with DSD, and (2) did not inhibit patient care in 2 patients with GCNIS.

Yolk sac tumor and dysgerminoma in the left gonad following gonadoblastoma in the right gonad in a 46,XY DSD with a novel SRY missense mutation: a case report

BACKGROUND

Approximately 10-15% of 46,XY disorders of sex development (DSDs) have an SRY mutation residing in the high mobility group (HMG) domain. Here, we present a case of 46,XY DSD caused by a novel missense mutation in the HMG region of SRY rapidly progressing to germ cell tumors (GCTs).

CASE PRESENTATION

An adolescent female (15 years old) exhibiting primary amenorrhea was later diagnosed as a 46,XY female with bilateral gonadal dysplasia on the basis of peripheral lymphocyte karyotype 46,XY and a novel missense mutation in SRY (c.281 T > G, p.L94R). The novel missense mutation (c.281 T > G, p.L94R) and its adjacent region were conserved. Protein structure analysis showed that the mutant site was located in the middle of the HMG domain, and the mutant protein had a diminished ability to bind to DNA. Imaging examination revealed an adolescent female with a naive uterus. Laparoscopy and initial pathological examination revealed left gonadal dysplasia and right gonadal dysplasia with gonadoblastoma (GB). Right gonadectomy by laparoscopy was performed upon consent from the patient's parents. Less than 1 year postoperatively, the left gonadal gland deteriorated as observed by the findings of a mass in the left adnexal region by pelvic MRI and serum AFP > 1000 ng/ml by serological tests, and then total hysterectomy and adnexal and left gonadectomy by laparoscopy were performed. The GCT stage was classified as stage Ic according to FIGO. At this time, pathologic examination showed that the left gonad had progressed to yolk sac tumor and dysgerminoma. The patient underwent chemotherapy post-operatively but developed type III myelosuppression and tumor recurrence several months later.

CONCLUSIONS

The patient initially presented with right gonadoblastoma but chose only right gonadectomy by laparoscopy to preserve the female sex characteristics, which resulted in rapid deterioration of the left gonad and poor treatment outcomes. This case demonstrates the importance of early genetic diagnosis and treatment of 46,XY female DSD.

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.

Spectrum of Germ Cell Tumor (GCT): 5 Years' Experience in a Tertiary Care Center and Utility of OCT4 as a Diagnostic Adjunct

Germ cell tumors (GCT) are an intriguing group of neoplasm having myriad clinical and morphological presentation. More and more transcription factors are being evaluated for identification of same. To study the spectrum of GCTs in a tertiary care center and the use of a stem cell marker OCT4 as a diagnostic adjunct, a retrospective 5-year (2008-2013) study was carried out. Immunohistochemistry (IHC) with OCT4 was performed on all cases and IHC for α feto protein (AFP), CD30, and epithelial membrane antigen (EMA) as per requirement. Cohort included 73 cases (23 males and 50 females). Testicular and ovarian GCTs accounted for 95.83% and 35.71% respectively. In males, seminoma was the commonest (34.78%) followed by mixed GCT (26%). 17.85% of ovarian GCTs were malignant mostly constituted by dysgerminoma (18%). Benign mature cystic teratoma (MCT) constituted 50% of ovarian GCTs. OCT4 immunoexpression was seen in all cases of seminoma/dysgerminoma, embryonal carcinoma, immature teratoma, and seminomatous/embryomatous component of mixed GCTs. Pure yolk sac tumor (YST) and MCT were consistently negative. OCT4 was especially helpful in identification of mixed GCT. A panel of immunohistochemical markers would be a more ideal way to identify and clarify the components because correct identification of the components is important for therapeutic intervention and prognostication. OCT4 being a primordial germ cell marker predicts aggressive behavior and targeted therapy against this should be investigated.

AZFa candidate gene UTY and its X homologue UTX are expressed in human germ cells

The Ubiquitous Transcribed Y (UTY a.k.a. KDM6C) AZFa candidate gene on the human Y chromosome and its paralog on the X chromosome, UTX (a.k.a. KDM6A), encode a histone lysine demethylase removing chromatin H3K27 methylation marks at genes transcriptional start sites for activation. Both proteins harbour the conserved Jumonji C (JmjC) domain, functional in chromatin metabolism, and an extended N-terminal tetratricopeptide repeat (TPR) block involved in specific protein interactions. Specific antisera for human UTY and UTX proteins were developed to distinguish the expression of both proteins in human germ cells by immunohistochemical experiments on appropriate tissue sections. In the male germ line, UTY was expressed in the fraction of A spermatogonia located at the basal membrane, probably including spermatogonia stem cells. UTX expression was more spread in all spermatogonia and in early spermatids. In female germ line, UTX expression was found in the primordial germ cells of the ovary. UTY was also expressed during fetal male germ cell development, whereas UTX expression was visible only at distinct gestation weeks. Based on these results and the conserved neighboured location of UTY and DDX3Y in Yq11 found in mammals of distinct lineages, we conclude that UTY, such as DDX3Y, is part of the Azoospermia factor a (AZFa) locus functioning in human spermatogonia to support the balance of their proliferation-differentiation rate before meiosis. Comparable UTY and DDX3Y expression was also found in gonadoblastoma and dysgerminoma cells found in germ cell nests of the dysgenetic gonads of individuals with disorders of sexual development and a Y chromosome in karyotype (DSD-XY). This confirms that AZFa overlaps with GBY, the Gonadoblastoma susceptibility Y locus, and includes the UTY gene.

Leydig Cell Tumor in a Patient with 46,XX Disorder of Sex Development (DSD), Ovotesticular: A Case Report and a Review of the Literature

Disorder of sex development (DSD) is a rare condition with atypical development of chromosomal, gonadal, or anatomical sex. It is classified in different subgroups based on the patient's karyotype, gonadal dysgenesis, and the appearance of the internal and external genitalia. Within the subgroups, the risk for developing neoplasms varies a lot. Here, we report the case of a 41-year-old patient with disorder of sex development, showing a 46,XX karyotype with an ovotestis and the simultaneous manifestation of a Leydig cell tumor in the ovotestis. The patient initially presented with infertility, and a suspicious lesion of the left testicle was noted on MRI-Scan. Upon resection, a Leydig cell tumor and an ovotestis were diagnosed. Nongerm call tumors are rare in patients with DSD. We report a nongerm cell tumor in a patient with 46,XX DSD, ovotesticular. This shows that although 46,XX DSD, ovotesticular is known to have a low potential for germ cell neoplasia, nongerm cell tumors can develop and should be into account for the management of those patients.

Disorders/Differences of Sex Development Presenting in the Newborn With 46,XY Karyotype

Differences/disorders of sex development (DSD) are a heterogeneous group of congenital conditions, resulting in discordance between an individual's sex chromosomes, gonads, and/or anatomic sex. The management of a newborn with suspected 46,XY DSD remains challenging. Newborns with 46,XY DSD may present with several phenotypes ranging from babies with atypical genitalia or girls with inguinal herniae to boys with micropenis and cryptorchidism. A mismatch between prenatal karyotype and female phenotype is an increasing reason for presentation. Gender assignment should be avoided prior to expert evaluation and possibly until molecular diagnosis. The classic diagnostic approach is time and cost-consuming. Today, a different approach may be considered. The first line of investigations must exclude rare life-threatening diseases related to salt wasting crises. Then, the new genetic tests should be performed, yielding increased diagnostic performance. Focused imaging or endocrine studies should be performed on the basis of genetic results in order to reduce repeated and invasive investigations for a small baby. The challenge for health professionals will lie in integrating specific genetic information with better defined clinical and endocrine phenotypes and in terms of long-term evolution. Such advances will permit optimization of counseling of parents and sex assignment. In this regard, society has significantly changed its attitude to the acceptance and expansion beyond strict binary male and female sexes, at least in some countries or cultures. These management advances should result in better personalized care and better long-term quality of life of babies born with 46,XY DSD.

17β-hydroxysteroid dehydrogenase type 3 deficiency: female sex assignment and follow-up

BACKGROUND

Deficiency of 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is a rare autosomal recessive 46,XY disorder of sex development (DSD). It is due to pathogenetic variants in the HSD17B3 gene. Mutated genes encode an abnormal enzyme with absent or reduced ability to convert Δ4-androstenedione (Δ4-A) to testosterone (T) in the fetal testis. Affected individuals are usually raised as females and diagnosis is made at puberty, when they show virilization.

METHODS

A girl with a presumptive diagnosis of complete androgen insensitivity syndrome underwent endocrine and genetic assessment. Long-term follow-up was reported.

RESULTS

The diagnosis of 17β-HSD3 deficiency was made (stimulated T/Δ4-A ratio: 0.15; HSD17B3 gene analysis: c.277+4A>T in intron 3/c.640_645del (p.Glu214_Glu215del) in exon 9. After extensive information, parents decided to maintain female sex. Gonadal removal was performed and histological evaluation demonstrated deep fibrosis of testicular tissue. Follow-up till 8.5 years of age showed somatic and neuro-psychological development fitting with the female sex.

CONCLUSIONS

Management of a child with the rare 17β-HSD3 deficiency remains challenging. Any decision must be carefully evaluated with parents. Long-term follow-up must be warranted by a multidisciplinary DSD team to evaluate the adequacy of the choices made on quality of life in later life.

5α-Reductase-2 deficiency: is gender assignment recommended in infancy? Two case-reports and review of the literature

PURPOSE

Gender assignment represents one of the most controversial aspects of the clinical management of individuals with Differences of Sex Development, including 5α-Reductase-2 deficiency (SRD5A2). Given the predominant female appearance of external genitalia in individuals with SRD5A2 deficiency, most of them were assigned to the female sex at birth. However, in the last years the high rate of gender role shift from female to male led to recommend a male gender assignment.

METHODS

We here describe two cases of subjects with SRD5A2 deficiency assigned as females at birth, reporting their clinical histories and psychometric evaluations (Body Uneasiness Test, Utrecht Gender Dysphoria Scale, Bem Sex-Role Inventory, Female Sexual Distress Scale Revised, visual analogue scale for gender identity and sexual orientation) performed at the time of referral at the Florence Gender Clinic.

RESULTS

Both patients underwent early surgical interventions without being included in the decision-making process. They had to conform to a binary feminine gender role because of social/familiar pressure, with a significant impact on their psychological well-being. Psychometric evaluations identified clinically significant body uneasiness and gender incongruence in both subjects. No sexually related distress and undifferentiated gender role resulted in the first subject and sexually related distress and androgynous gender role resulted in the second subject.

CONCLUSIONS

The reported cases suggest the possibility to consider a new approach for gender assignment in these individuals, involving them directly in the decision-making process and allowing them to explore their gender identity, also with the help of GnRH analogues to delay pubertal modifications.

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.

Novel Mutations Segregating with Complete Androgen Insensitivity Syndrome and their Molecular Characteristics

We analyzed three cases of Complete Androgen Insensitivity Syndrome (CAIS) and report three hitherto undisclosed causes of the disease. RNA-Seq, Real-timePCR, Western immunoblotting, and immunohistochemistry were performed with the aim of characterizing the disease-causing variants. In case No.1, we have identified a novel androgen receptor (AR) mutation (c.840delT) within the first exon in the N-terminal transactivation domain. This thymine deletion resulted in a frameshift and thus introduced a premature stop codon at amino acid 282. In case No.2, we observed a nonsynonymous mutation in the ligand-binding domain (c.2491C>T). Case No.3 did not reveal AR mutation; however, we have found a heterozygous mutation in CYP11A1 gene, which has a role in steroid hormone biosynthesis. Comparative RNA-Seq analysis of CAIS and control revealed 4293 significantly deregulated genes. In patients with CAIS, we observed a significant increase in the expression levels of PLCXD3, TM4SF18, CFI, GPX8, and SFRP4, and a significant decrease in the expression of SPATA16, TSACC, TCP10L, and DPY19L2 genes (more than 10-fold, p < 0.05). Our findings will be helpful in molecular diagnostics of patients with CAIS, as well as the identified genes could be also potential biomarkers for the germ cells differentiation process.

Gonadal Tissue Cryopreservation for a Girl With Partial Androgen Insensitivity Syndrome

Individuals with differences/disorders of sex development (DSD) have increased rates of infertility. For children and youth undergoing prophylactic gonadectomy for malignancy risk, our institution offers gonadal tissue cryopreservation, an experimental technique to preserve fertility cryopotential. An 11-year-old girl with partial androgen insensitivity syndrome presented for evaluation for fertility preservation in the setting of a planned bilateral gonadectomy at an outside institution. At presentation, the patient had begun puberty with an elevated serum androgen level and was experiencing undesired virilization. She expressed a strong female gender identity, an understanding of the various treatment options, and a preference for gonadectomy to prevent further virilization. After thorough counseling with the patient and family in our institution's multidisciplinary DSD clinic, she underwent bilateral gonadectomy with gonadal tissue cryopreservation. Her gonadal pathologic examination demonstrated well-developed peripubertal testes, with present, albeit decreased, numbers of spermatogonial germ cells, decreased Leydig cells, and nonspecific degenerative changes. The patient and her family chose to maintain the cryopreserved tissue for the patient's potential future use. To the best of our knowledge, the present case is the first reported case of gonadal tissue cryopreservation in a patient with partial androgen insensitivity syndrome. Storage of gonadal tissue is a feasible method of germ cell preservation in patients with DSD undergoing gonadectomy, although further research advances are required to facilitate development of this tissue into mature gametes capable of biological fertility.

Early development of a gonadal tumor in a patient with mixed gonadal dysgenesis

A gonadal tumor was diagnosed in the first months of life in a patient with genital ambiguity, a 45,X/46,XY karyotype, and mixed gonadal dysgenesis. Gonadal biopsies at the age of 3 months revealed dysgenetic testes and a gonadoblastoma on the right testis. Even though gonadal tumors are rare in childhood, this case indicates that prophylactic removal of dysgenetic gonads should be performed as early as possible, especially when the female sex is assigned to a patient with a Y-chromosome sequence.

45,X/46,XY ovotesticular disorder of sex development revisited: undifferentiated gonadal tissue may be mistaken as ovarian tissue

BACKGROUND

The 45,X/46,XY karyotype has been associated with mixed gonadal dysgenesis (MGD) and ovotesticular disorder of sex development (DSD). Our aim was to revise the diagnosis of ovotesticular DSD in two patients in the context of a retrospective study of 45,X/46,XY subjects with genital ambiguity.

CASE PRESENTATION

Patient 1 had a left streak gonad; the right one was considered an ovotestis. Patient 2 had a right testis; the left gonad was considered an ovary. Revision of the histological sections was performed. Both the "ovarian" part of the right gonad of patient 1 and the left "ovary" of patient 2 contained ovarian-type stroma with clusters of sex-cordlike structures and rare germ cells, compatible with undifferentiated gonadal tissue (UGT). Misdiagnosis of ovarian tissue in patients with 45,X/46,XY mosaicism or its variants could also be found in six published case reports.

CONCLUSIONS

A distinction between 45,X/46,XY ovotesticular DSD and MGD should be made on past and future cases keeping in mind that UGT may be mistaken as ovarian tissue.

Fluidity models in ancient Greece and current practices of sex assignment

Disorders of sexual differentiation such as androgen insensitivity and gonadal dysgenesis can involve an intrinsic fluidity at different levels, from the anatomical and biological to the social (gender) that must be considered in the context of social constraints. Sex assignment models based on George Engel's biopsychosocial aspects model of biology accept fluidity of gender as a central concept and therefore help establish expectations within the uncertainty of sex assignment and anticipate potential changes. The biology underlying the fluidity inherent to these disorders should be presented to parents at diagnosis, an approach that the gender medicine field should embrace as good practice. Greek mythology provides many accepted archetypes of change, and the ancient Greek appreciation of metamorphosis can be used as context with these patients. Our goal is to inform expertise and optimal approaches, knowing that this fluidity may eventually necessitate sex reassignment. Physicians should provide sex assignment education based on different components of sexual differentiation, prepare parents for future hormone-triggered changes in their children, and establish a sex-assignment algorithm.

The biology of germ cell tumors in disorders of sex development

Development of a malignant germ cell tumor, i.e., germ cell cancer (GCC) in individuals with disorders of sex development (DSD) depends on a number of (epi-)genetic factors related to early gonadal- and germ cell development, possibly related to genetic susceptibility. Fetal development of germ cells is orchestrated by strict processes involving specification, migration and the development of a proper gonadal niche. In this review we will discuss the early (epi-)genetic events in normal and aberrant germ cell and gonadal development. Focus will be on the formation of the precursor lesions of GCC in individuals who have DSD. In our view, expression of the different embryonic markers in, and epigenetic profile of the precursor lesions reflects the developmental stage in which these cells are blocked in their maturation. Therefore, these are not a primary pathogenetic driving force. Progression later in life towards a full blown cancer likely depends on additional factors such as a changed endocrine environment in a susceptible individual. Genetic susceptibility is, as evidenced by the presence of specific risk genetic variants (SNPs) in patients with a testicular GCC, related to genes involved in early germ cell and gonadal development.

Gender identity, gender assignment and reassignment in individuals with disorders of sex development: a major of dilemma

INTRODUCTION

Disorders of Sex Development (DSD) are a wide range of congenital conditions characterized by an incongruence of components involved in sexual differentiation, including gender psychosexual development. The management of such disorders is complex, and one of the most crucial decision is represented by gender assignment. In fact, the primary goal in DSD is to have a gender assignment consistent with the underlying gender identity in order to prevent the distress related to a forthcoming Gender Dysphoria. Historically, gender assignment was based essentially on surgical outcomes, assuming the neutrality of gender identity at birth. This policy has been challenged in the past decade refocusing on the importance of prenatal and postnatal hormonal and genetic influences on psychosexual development.

AIMS

(1) to update the main psychological and medical issues that surround DSD, in particular regarding gender identity and gender assignment; (2) to report specific clinical recommendations according to the different diagnosis.

METHODS

A systematic search of published evidence was performed using Medline (from 1972 to March 2016). Review of the relevant literature and recommendations was based on authors' expertise.

RESULTS

A review of gender identity and assignment in DSD is provided as well as clinical recommendations for the management of individuals with DSD.

CONCLUSIONS

Given the complexity of this management, DSD individuals and their families need to be supported by a specialized multidisciplinary team, which has been universally recognized as the best practice for intersexual conditions. In case of juvenile GD in DSD, the prescription of gonadotropin-releasing hormone analogues, following the World Professional Association for Transgender Health and the Endocrine Society guidelines, should be considered. It should always be taken into account that every DSD person is unique and has to be treated with individualized care. In this perspective, international registries are crucial to improve the understanding of these challenging conditions and clinical practice, in providing a better prediction of gender identity.

A novel morphological approach to gonads in disorders of sex development

Disorders of sex development are defined as congenital conditions with discordance between the phenotype, the genotype, the karyotype, and the hormonal profile. The disorders of sex development consensus classification established in 2005 are mainly based on chromosomal and biological data. However, histological anomalies are not considered. The aims of this study were to define the specific pathological features of gonads in various groups of disorders of sex development in order to clarify the nosology of histological findings and to evaluate the tumor risk in case of a conservative approach. One hundred and seventy-five samples from 86 patients with disorders of sex development were analyzed following a strict histological reading protocol. The term 'gonadal dysgenesis' for the histological analysis was found confusing and therefore excluded. The concept of 'dysplasia' was subsequently introduced in order to describe the architectural disorganization of the gonad (various degrees of irregular seminiferous tubules, thin albuginea, fibrous interstitium). Five histological types were identified: normal gonad, hypoplastic testis, dysplastic testis, streak gonad, and ovotestis. The analysis showed an association between undifferentiated gonadal tissue, a potential precursor of gonadoblastoma, and dysplasia. Dysplasia and undifferentiated gonadal tissue were only encountered in cases of genetic or chromosomal abnormality ('dysgenesis' groups in the disorders of sex development consensus classification). 'Dysgenetic testes', related to an embryonic malformation of the gonad, have variable histological presentations, from normal to streak. Conversely, gonads associated with hormonal deficiencies always display a normal architecture. A loss of expression of AMH and α-inhibin was identified in dysplastic areas. Foci of abnormal expression of the CD117 and OCT4 immature germ cells markers in dysplasia and undifferentiated gonadal tissue were associated with an increased risk of neoplasia. This morphological analysis aims at clarifying the histological classification and gives an indication of tumor risk of gonads in disorders of sex development.

Androgen insensitivity syndrome

Androgen insensitivity syndrome (AIS) results from androgen receptor dysfunction and is a common cause of disorder of sex development. The AIS phenotype largely depends on the degree of residual androgen receptor (AR) activity. This review describes the molecular action of androgens and the range of androgen receptor gene mutations, essential knowledge to understand the pathogenesis of the complete and partial forms of this syndrome. A multidisciplinary approach is recommended for clinical management from infancy through to adulthood. Hormone replacement therapy is needed following gonadectomy. Patients who choose to retain the gonads are at risk of developing germ cell tumors for which sensitive circulating tumor markers may soon become available. Whilst the contribution of AR dysfunction to complete AIS is well understood, the involvement of the AR and associated proteins as contributors to partial AIS is an area of active research. Disorders of sex development such as AIS which are related to AR dysfunction offer a breadth of manifestations for the clinician to manage and opportunities for further research on the mechanism of androgen action.

Disorders of sexual development

Disorders of sexual development (DSDs) are a group of disorders in which there is discordance between anatomic or hormonal sex and sex chromosome complement. These disorders present with ambiguity in the newborn period and require prompt evaluation to determine the underlying cause for treatment and appropriate sex assignment of the infant. Neonatologists should confer with a multidisciplinary team for the diagnostic evaluation and management of patients with DSDs. This article provides a review of normal sexual development, algorithms used for evaluating infants with ambiguous genitalia, and conditions that can present with ambiguous genitalia in the newborn period.

Magnetic resonance imaging of pediatric pelvic masses

Both benign and malignant pelvic masses are encountered in the pediatric population. Although ultrasonography remains the modality of choice for initial evaluation of a pediatric pelvic mass, in selected cases magnetic resonance (MR) imaging can add important diagnostic information. MR imaging has several advantages over ultrasonography and computed tomography, including superior contrast resolution and an ability to characterize abnormalities based on unique tissue characteristics. MR evaluation assists in lesion characterization, presurgical planning, and staging when a malignancy is suspected. MR imaging also offers a nonionizing imaging modality for long-term follow-up of patients undergoing therapy for malignant pelvic masses.

Management of children with disorders of sex development: 20-year experience in southern Thailand

BACKGROUND

Disorders of sex development (DSD) is a group of sexual differentiation disorders resulting in genital anomalies with defects in gonadal hormone synthesis and/or incomplete genital development. These conditions result in problems concerning the sex assignment of the child. This study aims to describe the clinical features, diagnosis and management of children with DSD in southern Thailand.

METHODS

The medical records of 117 pediatric patients diagnosed with DSD during the period of 1991-2011 were retrospectively reviewed.

RESULTS

Disorders of sex development were categorized into 3 groups: sex chromosome abnormalities (53.0%), 46,XX DSD (29.9%) and 46,XY DSD (17.1%). The two most common etiologies of DSD were Turner syndrome (36.8%) and congenital adrenal hyperplasia (29.9%). Ambiguous genitalia/intersex was the main problem in 46,XX DSD (94%) and 46,XY DSD (100%). Sex reassignment was done in 5 children (4.3%) at age of 3-5 years: from male to female in 4 children (1 patient with congenital adrenal hyperplasia, 1 patient with 45,X/46,XY DSD, and 2 patients with 46,XX ovotesticular DSD) and from female to male in 1 patient with 46,XX ovotesticular DSD. Of the total 20 children with 46,XY DSD, 16 (80%) were raised as females.

CONCLUSION

Management of DSD children has many aspects of concern. Sex assignment/reassignment depends on the phenotype (phallus size) of the external genitalia rather than the sex chromosome.

State of the art review in gonadal dysgenesis: challenges in diagnosis and management

Gonadal dysgenesis, a condition in which gonadal development is interrupted leading to gonadal dysfunction, is a unique subset of disorders of sexual development (DSD) that encompasses a wide spectrum of phenotypes ranging from normally virilized males to slightly undervirilized males, ambiguous phenotype, and normal phenotypic females. It presents specific challenges in diagnostic work-up and management. In XY gonadal dysgenesis, the presence of a Y chromosome or Y-chromosome material renders the patient at increased risk for developing gonadal malignancy. No universally accepted guidelines exist for identifying the risk of developing a malignancy or for determining either the timing or necessity of performing a gonadectomy in patients with XY gonadal dysgenesis. Our goal was to evaluate the literature and develop evidence-based medicine guidelines with respect to the diagnostic work-up and management of patients with XY gonadal dysgenesis. We reviewed the published literature and used the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) system when appropriate to grade the evidence and to provide recommendations for the diagnostic work-up, malignancy risk stratification, timing or necessity of gonadectomy, role of gonadal biopsy, and ethical considerations for performing a gonadectomy. Individualized health care is needed for patients with XY gonadal dysgenesis, and the decisions regarding gonadectomy should be tailored to each patient based on the underlying diagnosis and risk of malignancy. Our recommendations, based on the evidence available, add an important component to the diagnostic and management armament of physicians who treat patients with these conditions.

Molecular characteristics of malignant ovarian germ cell tumors and comparison with testicular counterparts: implications for pathogenesis

This review focuses on the molecular characteristics and development of rare malignant ovarian germ cell tumors (mOGCTs). We provide an overview of the genomic aberrations assessed by ploidy, cytogenetic banding, and comparative genomic hybridization. We summarize and discuss the transcriptome profiles of mRNA and microRNA (miRNA), and biomarkers (DNA methylation, gene mutation, individual protein expression) for each mOGCT histological subtype. Parallels between the origin of mOGCT and their male counterpart testicular GCT (TGCT) are discussed from the perspective of germ cell development, endocrinological influences, and pathogenesis, as is the GCT origin in patients with disorders of sex development. Integrated molecular profiles of the 3 main histological subtypes, dysgerminoma (DG), yolk sac tumor (YST), and immature teratoma (IT), are presented. DGs show genomic aberrations comparable to TGCT. In contrast, the genome profiles of YST and IT are different both from each other and from DG/TGCT. Differences between DG and YST are underlined by their miRNA/mRNA expression patterns, suggesting preferential involvement of the WNT/β-catenin and TGF-β/bone morphogenetic protein signaling pathways among YSTs. Characteristic protein expression patterns are observed in DG, YST and IT. We propose that mOGCT develop through different developmental pathways, including one that is likely shared with TGCT and involves insufficient sexual differentiation of the germ cell niche. The molecular features of the mOGCTs underline their similarity to pluripotent precursor cells (primordial germ cells, PGCs) and other stem cells. This similarity combined with the process of ovary development, explain why mOGCTs present so early in life, and with greater histological complexity, than most somatic solid tumors.

Clinical and gonadal features and early surgical management of 45,X/46,XY and 45,X/47,XYY chromosomal mosaicism presenting with genital anomalies

OBJECTIVE

The 45,X/46,XY and 45,X/47,XYY group of patients includes some of those previously diagnosed with 'mixed gonadal dysgenesis'. Our aim was to establish the clinical and gonadal spectrum, and early surgical management, of patients with chromosomal mosaicism presenting with genital anomalies.

PATIENTS AND METHODS

We performed a retrospective review of patients with 45,X/46,XY or 45,X/47,XYY mosaicism presenting with genital ambiguity between 1988 and 2009. At least one gonadal biopsy or gonadectomy specimen was available for each patient. Gonadal histology was re-evaluated by a paediatric pathologist.

RESULTS

Of 31 patients with 45,X/46,XY (n = 28) or 45,X/47,XYY (n = 3) mosaicism and genital anomalies, 19 (61%) were raised male. Histology of 46 gonads was available from patients who had undergone a gonadectomy or gonadal biopsy, at a median age of 9.5 months. 18 gonads were palpable at presentation, including 5 (28%) histologically unremarkable testes, 2 streak gonads, and 1 dysgenetic gonad with distinct areas of testicular and ovarian stroma but no oocytes. All intra-abdominal gonads were found to be dysgenetic testes (of which 2 were noted to have pre-malignant changes) or streaks, apart from 1 histologically unremarkable testis. 15 (48%) patients had other anomalies, most commonly cardiac and renal; 4 (13%) had a Turner phenotype.

CONCLUSION

The anatomy and gonadal histology of 45,X/46,XY and 45,X/47,XYY individuals with genital ambiguity do not conform to a set pattern, and hence management of each patient should be individualized according to detailed anatomical and histological assessment.

The rise of testicular germ cell tumours: the search for causes, risk factors and novel therapeutic targets

Since the beginning of the 20th century there has been a decline in the reproductive vitality of men within the Western world. The declining sperm quantity and quality has been associated with increased overt disorders of sexual development including hypospadias, undescended testes and type II testicular germ cell tumours (TGCTs). The increase in TGCTs cannot be accounted for by genetic changes in the population. Therefore exposure to environmental toxicants appears to be a major contributor to the aetiology of TGCTs and men with a genetic predisposition are particularly vulnerable. In particular, Type II TGCTs have been identified to arise from a precursor lesion Carcinoma in situ (CIS), identified as a dysfunctional gonocyte; however, the exact triggers for CIS development are currently unknown. Therefore the transition from gonocytes into spermatogonia is key to those studying TGCTs. Recently we have identified seven miRNA molecules (including members of the miR-290 family and miR-136, 463* and 743a) to be significantly changed over this transition period. These miRNA molecules are predicted to have targets within the CXCR4, PTEN, DHH, RAC and PDGF pathways, all of which have important roles in germ cell migration, proliferation and homing to the spermatogonial stem cell niche. Given the plethora of potential targets affected by each miRNA molecule, subtle changes in miRNA expression could have significant consequences e.g. tumourigenesis. The role of non-traditional oncogenes and tumour suppressors such as miRNA in TGCT is highlighted by the fact that the majority of these tumours express wild type p53, a pivotal tumour suppressor usually inactivated in cancer. While treatment of TGCTs is highly successful, the impact of these treatments on fertility means that identification of exact triggers, earlier diagnosis and alternate treatments are essential. This review examines the genetic factors and possible triggers of type II TGCT to highlight target areas for potential new treatments.

Gender Development in 46,XY DSD: Influences of Chromosomes, Hormones, and Interactions with Parents and Healthcare Professionals

Variables that impact gender development in humans are difficult to evaluate. This difficulty exists because it is not usually possible to tease apart biological influences on gender from social variables. People with disorders of sex development, or DSD, provide important opportunities to study gender within individuals for whom biologic components of sex can be discordant with social components of gender. While most studies of gender development in people with 46,XY DSD have historically emphasized the importance of genes and hormones on gender identity and gender role, more recent evidence for a significant role for socialization exists and is considered here. For example, the influence of parents' perceptions of, and reactions to, DSD are considered. Additionally, the impact of treatments for DSD such as receiving gonadal surgeries or genitoplasty to reduce genital ambiguity on the psychological development of people with 46,XY DSD is presented. Finally, the role of multi-disciplinary care including access to peer support for advancing medical, surgical and psychosexual outcomes of children and adults with 46,XY DSD, regardless of sex of rearing, is discussed.

Estrogens promote proliferation of the seminoma-like TCam-2 cell line through a GPER-dependent ERα36 induction

Seminoma, originated from carcinoma in situ cells (CIS), is one of the main causes of cancer in young men. Postpubertal development of these testicular germ cell tumors suggests a hormone-sensitive way of CIS cell proliferation induction. Using the unique seminoma TCam-2 cell line, we demonstrate that both estradiol and testosterone can stimulate TCam-2 cell proliferation in the absence of the estradiol receptor ERα. We establish that estradiol can activate GPER-cAMP/PKA signalling pathway. TCam-2 cells express ERα36, a truncated isoform of the canonical ERα receptor, the expression of which is rapidly induced after estrogen treatment in a GPER-dependent manner. ERα36 knockdown indicates that ERα36 is (i) a downstream target of E(2)-activated GPER/PKA/CREB pathway, (ii) required for estradiol-dependent EGFR expression, (iii) necessary for cell proliferation. Colocalization of ERα36 with cytoskeleton microfilaments suggests a role of estrogens in cell motility. Our results highlight the functional role of ERα36 in context of seminoma cell proliferation and the importance of testing ERα36 in vivo as a possible future prognostic marker.

A model of delivering multi-disciplinary care to people with 46 XY DSD

In 2006, a consensus statement was jointly produced by the Lawson Wilkins Pediatric Endocrine Society (LWPES) and the European Society of Paediatric Endocrinology (ESPE) concerning the management of disorders of sex development (DSD) [1]. A recommendation provided by this consensus was that evaluation and long-term care for people affected by DSD should be performed at medical centers with multi-disciplinary teams experienced in such conditions. Here we provide our team's interpretation of the 2006 consensus statement recommendations and its translation into a clinical protocol for individuals affected by 46 XY DSD with either female, or ambiguous, genitalia at birth. Options for medical and surgical management, transitioning of care, and the use of mental health services and peer support groups are discussed. Finally, we provide preliminary data to support the application of our model for delivering multi-disciplinary care and support to patients and their families.

Undifferentiated gonadal tissue, Y chromosome instability, and tumors in XY gonadal dysgenesis

Patients with XY gonadal dysgenesis are at increased risk of developing gonadal tumors. The etiology of several cases of XY gonadal dysgenesis remains unknown, but X/XY gonadal mosaicism has been hypothesized to play a role. At the histologic level, the presence of persistent primitive sex cords containing immature germ cells in dysgenetic gonads (an entity called undifferentiated gonadal tissue, or UGT) was recently described, and these immature germ cells are thought to be at risk of neoplastic transformation. To further investigate both these aspects, we retrospectively studied the gonads from 30 patients with pure (22) and mixed (8) gonadal dysgenesis. Cytogenetic analyses performed on 35 gonads revealed that structurally abnormal Y chromosomes were lost in a majority of cells from the gonads, explaining the gonadal dysgenesis of patients bearing a rearranged Y chromosome. On the other hand, normal Y chromosomes were less often lost in gonads of patients with gonadal dysgenesis. At the histologic level, 43 of the 51 gonads presented areas characteristic of a streak; 13 of these streak gonads also presented areas of UGT. Structures resembling sex cords but without germ cells were found in many of the streaks not containing UGT, suggesting that UGT was initially present. Of the 13 gonads containing both UGT and a streak, 9 developed a tumor. The proximity of UGT with the tumors as well as the immunostaining patterns (PLAP+, OCT3/4+, and CD117/KIT+) suggests that germ cells found in UGT are a risk factor for gonadal tumors.

Imaging of pediatric ovarian neoplasms

We review the clinical and imaging characteristics of the most common ovarian neoplasms in children and adolescents. Because of the widespread use of diagnostic imaging, incidental ovarian neoplasms might be encountered during the evaluation of abdominal pain, trauma or other indications and might pose a diagnostic dilemma. Conducting adequate imaging studies under these conditions is important, as management strategies differ according to the size and appearance of the lesion as well as the age of the patient. US dominates in gynecological imaging because of its excellent visualization, absence of ionizing radiation and sedation risks and comparatively low cost. For further examination of indeterminate lesions found using US, MRI is being used more progressively in this field, particularly for the evaluation of complex pelvic masses with the aim of distinguishing benign and malignant conditions and conditions requiring surgical intervention. CT is reserved primarily for tumor staging and follow-up and for emergency situations.

Gonadal development and tumor formation at the crossroads of male and female sex determination

Malignant germ cell tumor (GCT) formation is a well-known complication in the management of patients with a disorder of sex development (DSD). DSDs are defined as congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. DSD patients in whom the karyotype - at least at the gonadal level - contains (a part of) the Y chromosome are at increased risk for neoplastic transformation of germ cells, leading to the development of the so-called 'type II germ cell tumors'. However, tumor risk in the various forms of DSD varies considerably between the different diagnostic groups. This contribution integrates our actual knowledge on the pathophysiology of tumor development in DSDs, recent findings on gonadal (mal)development in DSD patients, and possible correlations between the patient's phenotype and his/her risk for germ cell tumor development.

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

CONTEXT

Gonadectomy is avoided whenever possible in boys with 45,X/46,XY. However, no clinical markers are currently available to guide clinicians in predicting gonadal tumor risk or hormone production.

OBJECTIVE

The objective of the study was to test the hypothesis that gonadal histology and risk for development of a malignant germ cell tumor are reflected by the clinical presentation of a 45,X/46,XY individual.

DESIGN

The design of the study was the correlation of clinical data [external masculinization score (EMS), pubertal outcome] with pathology data (gonadal phenotype, tumor risk).

SETTING

This was a multicenter study involving two multidisciplinary disorder of sex development teams.

PATIENTS

Patients included genetically proven 45,X/46,XY (and variants) cases, of whom at least one gonadal biopsy or gonadectomy specimen was available, together with clinical details.

INTERVENTIONS

Patients (n = 48) were divided into three groups, based on the EMS. Gonadal histology and tumor risk were assessed on paraffin-embedded samples (n = 87) by morphology and immunohistochemistry on the basis of established criteria.

MAIN OUTCOME MEASURES

Gonadal differentiation and tumor risk in the three clinical groups were measured. Clinical outcome in patients with at least one preserved gonad was also measured.

RESULTS

Tumor risk in the three groups was significantly related to the gonadal differentiation pattern (P < 0.001). In boys, hormone production was sufficient and was not predicted by the EMS.

CONCLUSIONS

The EMS reflects gonadal differentiation and tumor risk in patients with 45,X/46,XY. In boys, testosterone production is often sufficient, but strict follow-up is warranted because of malignancy risk, which appears inversely related to EMS. In girls, tumor risk is limited but gonads are not functional, making gonadectomy the most reasonable option.

Clinical and genetic characterization of complete androgen insensitivity syndrome in a Chinese family

We studied a family with two cousins who were diagnosed with complete androgen insensitivity syndrome, an X-linked disorder caused by mutations in the androgen receptor gene. A pedigree analysis and a molecular study using PCR and DNA sequencing clarified each female family member's androgen receptor status and revealed a mutation consisting of the deletion of exon 2 and surrounding introns of the androgen receptor gene. Based on the relative nucleotide positions, we concluded that the deletion mutation in exon 2 and its surrounding introns was approximately 6000 to 7000 bp. This mutation, never previously fully characterized using DNA sequencing, was responsible for complete androgen insensitivity syndrome in this family. Pedigree analysis with a molecular study of the androgen receptor gene in affected families facilitates genetic counseling provided to family members.

Gonadal tumours and DSD

Disorders of sex development (DSD), previously referred to as intersex, has been recognised as one of the main risk factors for development of type II germ cell tumours (GCTs), that is, seminomas/dysgerminomas and non-seminomas (e.g., embryonal carcinoma, yolk sac tumour, choriocarcinoma and teratoma). Within the testis, this type of cancer is the most frequent malignancy in adolescent and young adult Caucasian males. Although these males are not known to have dysgenetic gonads, the similarities in the resulting tumours suggest a common aetiological mechanism(s),--genetically, environmentally or a combination of both. Within the group of DSD patients, being in fact congenital conditions, the risk of malignant transformation of germ cells is highly heterogeneous, depending on a number of parameters, some of which have only recently been identified. Understanding of these recent insights will stimulate further research, with the final aim to develop an informative clinical decision tree for DSD patients, which includes optimal (early) diagnosis without overtreatment, such as prophylactic gonadectomy in the case of a low tumour risk.

Long-term health issues of women with XY karyotype

46XY women is a label that gathers together a number of different conditions for which the natural history in to adult life is still only partially known. A common feature is the difficulty that many women encounter when approaching clinicians. In this review we assemble medical, surgical and psychological literature pertaining adult 46XY women together with our experience gained from an adult DSD clinic. There is increasing awareness for the need for multidisciplinary team involving endocrinologist, gynaecology, nurse specialist and particularly clinical psychologists. Management of adult women with a 46XY karyotype includes several aspects: revising the diagnosis in those with previously incomplete workup; exploring issues of disclosure of details of the diagnosis. Surgery needs to be discussed when the gonads are still in situ and when partial virilisation of genitalia have occurred. To maintain secondary sexual characteristics, for general well being and for bone health, most women require sex steroid replacement continuously until the approximately age of 50 and it is important that the treatment is tailored on individual basis. Women should have access to advice about fertility options involving egg donation and surrogacy.