The risk for the development of germ cell tumors is an important factor to deal with in the management of patients with disorders of sex development (DSD). However, this risk is often hard to predict. Recently, major progress has been made in identifying gene-products related to germ cell tumor development (testis-specific protein-Y encoded and octamer binding transcription factor 3/4) and in recognizing early changes of germ cells (maturation delay, preneoplastic lesions, and in situ neoplasia). The newly recognized “undifferentiated gonadal tissue” has been identified as a gonadal differentiation pattern bearing a high risk for the development of gonadoblastoma. It is expected that the combination of these findings will allow for estimation of the risk for tumor development in the individual patient (high risk/intermediate risk/low risk). This article reviews the recent literature regarding the prevalence of germ cell tumors in patients with DSD. Some major limitations regarding this topic, including a confusing terminology referring to the different forms of intersex disorders and unclear criteria for the diagnosis of malignant germ cells at an early age (maturation delay vs. early steps in malignant transformation) are discussed. Thereafter, an overview of the recent advances that have been made in our knowledge of germ cell tumor development and the correct diagnosis of early neoplastic lesions in this patient population is provided. A new classification system for patients with DSD is proposed as a tool to refine our insight in the prevalence of germ cell tumors in specific diagnostic groups.

The term differences of sex development (DSDs; also known as disorders of sex development) refers to a heterogeneous group of congenital conditions affecting human sex determination and differentiation. Several reports highlighting suboptimal physical and psychosexual outcomes in individuals who have a DSD led to a radical revision of nomenclature and management a decade ago. Whereas the resulting recommendations for holistic, multidisciplinary care seem to have been implemented rapidly in specialized paediatric services around the world, adolescents often experience difficulties in finding access to expert adult care and gradually or abruptly cease medical follow-up. Many adults with a DSD have health-related questions that remain unanswered owing to a lack of evidence pertaining to the natural evolution of the various conditions in later life stages. This Consensus Statement, developed by a European multidisciplinary group of experts, including patient representatives, summarizes evidence-based and experience-based recommendations for lifelong care and data collection in individuals with a DSD across ages and highlights clinical research priorities. By doing so, we hope to contribute to improving understanding and management of these conditions by involved medical professionals. In addition, we hope to give impetus to multicentre studies that will shed light on outcomes and comorbidities of DSD conditions across the lifespan.

Disorders of sex development (DSD) are congenital conditions in which chromosomal, gonadal, or phenotypic sex is atypical. Clinical management of DSD is often difficult and currently only 13% of patients receive an accurate clinical genetic diagnosis. To address this we have developed a massively parallel sequencing targeted DSD gene panel which allows us to sequence all 64 known diagnostic DSD genes and candidate genes simultaneously. We analyzed DNA from the largest reported international cohort of patients with DSD (278 patients with 46,XY DSD and 48 with 46,XX DSD). Our targeted gene panel compares favorably with other sequencing platforms. We found a total of 28 diagnostic genes that are implicated in DSD, highlighting the genetic spectrum of this disorder. Sequencing revealed 93 previously unreported DSD gene variants. Overall, we identified a likely genetic diagnosis in 43% of patients with 46,XY DSD. In patients with 46,XY disorders of androgen synthesis and action the genetic diagnosis rate reached 60%. Surprisingly, little difference in diagnostic rate was observed between singletons and trios. In many cases our findings are informative as to the likely cause of the DSD, which will facilitate clinical management. Our massively parallel sequencing targeted DSD gene panel represents an economical means of improving the genetic diagnostic capability for patients affected by DSD. Implementation of this panel in a large cohort of patients has expanded our understanding of the underlying genetic etiology of DSD. The inclusion of research candidate genes also provides an invaluable resource for future identification of novel genes.

In women with vaginal hypoplasia, such as in Mayer–Rokitansky–Küster–Hauser syndrome (MRKH) and in Complete Androgen Insensitivity Syndrome (CAIS), surgical vaginoplasty and non-surgical self-dilation treatments are available to lengthen the vagina and facilitate sexual intercourse, but the best treatment remains controversial. Vaginal dilation has been recommended as a first-line treatment, because of its less invasive character and high success rate. However, the exploration of factors associated with compliance and long-term outcome is incomplete, including whether psychological counselling needs to be embedded in treatment to maximize efficacy. It is not known if failed vaginal dilation therapy jeopardizes further surgical success outcomes, especially because in a number of these procedures ongoing vaginal dilation is required. In addition, if surgery is needed, there is a lack of evidence to inform physicians regarding the optimum surgical technique to use. Also, it is unclear whether maintenance dilation therapy in case of sexual inactivity is crucial to ensure functional success. In view of this ongoing debate, we performed a search of all published literature (English language only) restricted to the management of vaginal hypoplasia in patients with MRKH or CAIS from 1898 to March 2013 using Pubmed, Cochrane Library and Web of Science. Of the 6700 articles initially identified, a total of 190 studies are analysed. More specifically, by establishing the risk/efficacy profile (vaginal capacity, complications and long-term durability in terms of sexual function) of the different surgical and non-surgical reconstruction techniques, we evaluate if vaginal dilation proposed as the first-line technique is justified based on the evidence. When anatomical success was defined as a length of ≥7 cm and functional success as coitus, all vaginoplasty techniques yielded significantly higher success rates (>90 versus 75% after vaginal dilation), irrespective of underlying diagnosis or start vaginal length. When functional success was defined as ‘satisfaction with sex’, including non-genital sex, differences disappeared. Failed dilation therapy does not preclude anatomical (nor functional) success if vaginoplasty afterwards is necessary. Traction vaginoplasty seems to have the highest anatomical (99%) and functional success rates (96%), whereas both split- and full-thickness skin graft procedures and intestinal procedures have the lowest successful outcomes (83–95%). Overall, complication rates were significantly lower within the vaginal dilation groups when compared with the different vaginoplasty techniques. Although no randomized control data exist regarding maintenance dilation, the available evidence suggests that continued dilation is needed to maintain patency in periods of coital inactivity. Despite the expectancy that the probability of further positive outcomes is maximized with psychological counselling, this could not be confirmed. As the medical literature lacks high-quality comparative outcome studies and prospective, longitudinal studies are scarce, no evidence-based treatment guidelines can be provided. However, because of the physically low complication rate and an overall success chance of 75%, vaginal dilation as first choice treatment seems to be justified. Overall, the laparoscopic Vecchietti procedure, becoming more and more available in specialized centres, is considered an appropriate surgical option in patients who are poorly compliant and failed dilation therapy, or for those who do not want to start with vaginal dilation therapy. Future approaches need to raise a wider range of psychosexually oriented questions, elucidate the relationship between vaginal depth and satisfactory outcomes and gain additional experience concerning the format of acceptable and efficient psychological care.

The purpose of the study was to define the histological origin of gonadoblastomas, allowing the identification of high-risk patients. Sixty paraffin-embedded gonadectomy or gonadal biopsy samples of 43 patients with gonadal dysgenesis were selected from our archives. We studied the morphology and immunohistochemical properties of the germ cells in 40 samples without neoplastic transformation and compared these findings with the morphological and immunohistochemical characteristics of 20 samples containing gonadoblastoma/dysgerminoma. The overall incidence of germ cell tumors in our patient series was 35%. In dysgenetic gonads without germ cell neoplasia, besides the presence of areas with testicular and/or ovarian differentiation, areas of undifferentiated gonadal tissue were identified in 13 of 40 samples (32.5%). A subpopulation of germ cells within these undifferentiated areas stained positive for octamer binding transcription factor (OCT)3/4, the stem cell factor receptor, placental-like alkaline phosphatase, and testis-specific protein-Y encoded. Gonadoblastoma germ cells display identical staining results. Moreover, in gonads containing gonadoblastoma, adjacent to this lesion, areas of undifferentiated gonadal tissue with identical immunohistochemical characteristics were identified in 10 of 20 samples (50%). No adjacent tissue was available in five cases, whereas in the five remaining cases, it consisted of streak tissue. In three cases, an accumulation of OCT3/4-positive germ cells in the proximity of the malignant lesions was found, suggesting clonal expansion and final organization into gonadoblastoma nests. Based on these observations, we hypothesize that gonadoblastomas originate from surviving OCT3/4-positive germ cells in areas of undifferentiated gonadal tissue within the dysgenetic gonad. Supportive evidence was obtained that carcinoma in situ arises in regions with testicular differentiation.