Gonadoblastoma in Turner syndrome and Y-chromosome-derived material

Challenges in the management of Turner syndrome with Y chromosome material: a case report of prophylactic gonadectomy revealing dysgerminoma

Turner syndrome (TS) patients with Y chromosome material face an increased risk of gonadal germ cell tumors (GCTs). This case report discusses the challenges in decision-making regarding prophylactic gonadectomy, considering the risk of malignancy and the desire to preserve fertility. We report a case of a 12-year-old female with mosaic TS and Y chromosome material who initially presented with short stature and obesity. Karyotype analysis showed a mixed cell line (45X and 46XY). Counseling about the increased risk of developing GCT and preservation of gonadal function was provided, and we decided to delay gonadectomy until the age of 12. Prophylactic bilateral gonadectomy revealed dysgerminoma associated with GB at the age of 12. Fortunately, the patient was asymptomatic, with no additional therapy required due to the early stage of the disease. The case highlights the dilemma in managing TS patients with Y chromosome material, where the risk of GCT varies depending on the type of difference in sex development and gonadal function. The decision to delay gonadectomy reflects the emphasis on preservation of ovarian, although it poses a risk of malignancy. This case underscores the importance of individualized care in TS patients with Y chromosome material, balancing the risk of malignancy against preservation of ovarian. It emphasizes the need for timely and personalized decision-making in prophylactic gonadectomy.

The Use of Fluorescence In situ Hybridisation in the Diagnosis of Hidden Mosaicism in Egyptian Patients with Turner Syndrome

Background

Turner syndrome (TS) is the most common chromosomal abnormality in females. The diagnosis of TS is based on karyotyping of 30 blood lymphocytes. This technique does not rule out tissue mosaicism or low-grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome.

Aims

This study was set to determine the value of additional genetic studies such as fluorescent in situ hybridisation and the inclusion of buccal cells in search for mosaicism in TS patients.

Settings and Design

This cross-sectional, descriptive study was performed in Human Genetics Department, Medical Research Institute, Alexandria University.

Materials and Methods

Fluorescence in situ hybridisation technique was applied to lymphocyte cultures as well as buccal smears using centromeric probes for X and Y chromosomes. Genotype phenotype correlation was also evaluated.

Statistical Analysis Used

Descriptive study where categorical variables were described using number and percentage and continuous variables were described using mean and standard deviation.

Results

Fluorescence in situ hybridisation technique study detected hidden mosaicism in 60% of studied patients; 20% of patients had a cell line containing Y material, while 40% had variable degrees of X, XX mosaicism, and in the remaining 40% no second cell line was detected. Fluorescence in situ hybridisation study helped identify the origin of the marker to be Y in all patients. The introduction of an additional cell line helped in identifying mosaicism in patients with monosomy X. Virilisation signs were only observed among TS patients with Y cell line mosaicism. The clinical manifestations were more severe in patients with monosomy X than other mosaic cases.

Conclusions

Molecular cytogenetic investigation for all suspected cases of TS should be considered for appropriate treatment plan and genetic counselling.

Comprehensive analysis of three female patients with different types of X/Y translocations and literature review

BACKGROUND

X/Y translocations are highly heterogeneity in terms of clinical genetic effects, and most patients lack complete pedigree analysis for clinical and genetic characterization.

RESULTS

This study comprehensively analyzed the clinical and genetic characteristics of three new patients with X/Y translocations. Furthermore, cases with X/Y translocations reported in the literature and studies exploring the clinical genetic effects in patients with X/Y translocations were reviewed. All three female patients were carriers of X/Y translocations with different phenotypes. The karyotype for patient 1 was 46,X,der(X)t(X;Y)(p22.33;q12)mat, patient 2 was 46,X,der(X)t(X;Y)(q21.2;q11.2)dn, and patient 3 was 46,X,der(X)t(X;Y)(q28;q11.223)t(Y;Y)(q12;q11.223)mat. C-banding analysis of all three patients revealed a large heterochromatin region in the terminal region of the X chromosome. All patients underwent chromosomal microarray analysis, which revealed the precise copy number loss or gain. Data on 128 patients with X/Y translocations were retrieved from 81 studies; the phenotype of these patients was related to the breakpoint of the chromosome, size of the deleted region, and their sex. We reclassified the X/Y translocations into new types based on the breakpoints of the X and Y chromosomes.

CONCLUSION

X/Y translocations have substantial phenotypic diversity, and the genetic classification standards are not unified. With the development of molecular cytogenetics, it is necessary to combine multiple genetic methods to obtain an accurate and reasonable classification. Thus, clarifying their genetic causes and effects promptly will help in genetic counseling, prenatal diagnosis, preimplantation genetic testing, and improvement in clinical treatment strategies.

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.

New insights into the comorbid conditions of Turner syndrome: results from a long-term monocentric cohort study

PURPOSE

Many questions concerning Turner syndrome (TS) remain unresolved, such as the long-term complications and, therefore, the optimal care setting for adults. The primary aim of this long-term cohort study was to estimate the incidence of comorbid conditions along the life course.

METHODS

A total of 160 Italian patients with TS diagnosed from 1967 to 2010 were regularly and structurally monitored from the diagnosis to December 2019 at the University Hospital of Bologna using a structured multidisciplinary monitoring protocol.

RESULTS

The study cohort was followed up for a median of 27 years (IQR 12-42). Autoimmune diseases were the comorbid condition with the highest incidence (61.2%), followed by osteoporosis and hypertension (23.8%), type 2 diabetes (16.2%) and tumours (15.1%). Median age of onset ranged from 22 years for autoimmune diseases to 39 years for type 2 diabetes. Malignant tumours were the most prominent type of neoplasm, with a cumulative incidence of 11.9%. Papillary thyroid carcinoma was the most common form of cancer, followed by skin cancer and cancer of the central nervous system. Only one major cardiovascular event (acute aortic dissection) was observed during follow-up. No cases of ischaemic heart disease, heart failure, stroke or death were recorded.

CONCLUSIONS

This cohort study confirms the need for continuous, structured and multidisciplinary lifelong monitoring of TS, thus ensuring the early diagnosis of important comorbid conditions, including cancer, and their appropriate and timely treatment. In addition, these data highlight the need for the increased surveillance of specific types of cancer in TS, including thyroid carcinoma.

Population Prevalence, Cancer Risk, and Mortality Risk of Turner Syndrome in South Korean Women Based on National Health Insurance Service Data

PURPOSE

In South Korea, investigations into Turner syndrome (TS) prevalence and TS-associated cancer and mortality are lacking. Accurate data were estimated from the National Health Insurance Service (NHIS) and the Rare Diseases Registry (RDR) records.

MATERIALS AND METHODS

Data on patients with TS who were registered in the RDR between 2007 and 2017 were collected. To estimate TS-associated cancer and mortality risk, the data were compared with data of 1:3 age-matched controls.

RESULTS

In 2017, 2054 patients with TS were identified from a total population of 26186952 South Korean women; therefore, the prevalence was 7.84 per 100000 persons. TS prevalence across 10-year interval age groups were 11.82, 23.17, 18.37, 10.49, 4.09, and 0.38 for age under 10 years, teenagers, 20s, 30s, 40s, and older than 50, respectively (per 100000 persons). The cancer risk in patients with TS was higher than that of age-matched controls over 5.3 person-years [hazard ratio (HR)=1.82, 95% confidence interval (CI) 1.01-3.27, p=0.045]. Among different types of cancer, thyroid cancer risk in patients with TS was significantly higher than that of age-matched controls (HR=2.78, 95% CI 1.06-7.26, p=0.037). We also observed that TS-associated all-cause mortality risk was higher than that of age-matched controls (HR=3.36, 95% CI 1.59-7.10, p=0.002).

CONCLUSION

National prevalence of TS was suggested, and an increased risk of TS-associated thyroid cancer and mortality were observed in this study.

The Care of Adolescents and Young Adults with Turner Syndrome: A Pediatric and Adolescent Gynecology Perspective

Turner syndrome (TS) is caused by the absence of a part or whole X chromosome in a phenotypic female and has an estimated prevalence of 25-50/100,000 live-born females. The primary gynecologic manifestation of TS is primary ovarian insufficiency (POI), and the resulting hypoestrogenism and infertility are experienced by most individuals with TS. In this review, we summarize the recommendations for the care of adolescents and young adults with TS, with a focus on primary ovarian insufficiency in TS, hormone replacement therapy, fertility preservation, and pregnancy in TS.

Added value of buccal cell FISH analysis in the diagnosis and management of Turner syndrome

STUDY QUESTION

Is there an added diagnosis value of buccal cell FISH analysis compared with blood lymphocyte chromosomal investigations in patients with Turner syndrome (TS)?

SUMMARY ANSWER

Buccal cell FISH analysis, a non-invasive technique, modified the chromosomal results obtained with the blood karyotype in 17 patients (12%) of our cohort.

WHAT IS KNOWN ALREADY

Few studies have evaluated buccal cell FISH analysis and compared them with blood karyotype in patients with TS.

STUDY DESIGN, SIZE, DURATION

A prospective, monocentric cohort study was conducted in a rare diseases centre (CMERC) between July 2017 and August 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 142 adult patients with TS, and at least 5% 45,X cells in a previous blood karyotype, were recruited. All the patients' files were included in the CEMARA database. This national database has been declared to the French data protection agency (CNIL approval number 1187326). In compliance with French law, consent regarding non-opposition to collect and use the data was obtained from each patient. A FISH analysis on a buccal smear was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

The percentage of 45,X cells was identical between the two tissues in only 32.4% of cases. The discrepancy was higher than 41% for 12% of the cohort. The percentage of 45,X cells was higher in blood in 53 (37.3%) patients, and higher in buccal cells in 43 (30.3%) of cases. In 17 (12%) cases, the blood karyotype had to be reconsidered in regard to the buccal cell analysis.

LIMITATIONS, REASONS FOR CAUTION

It would have been interesting to evaluate karyotypes in cells from other tissues such as cells from skin biopsy or from the urinary tract and even from blood vessels or gonads in case of surgery and to compare them with each patient's phenotype. However, most of the time, these tissues are not available.

WIDER IMPLICATIONS OF THE FINDINGS

Although blood lymphocyte karyotype remains the gold standard for the diagnosis of TS, buccal cell FISH analysis is an efficient tool to evaluate the global chromosomal constitution in these patients, thus allowing them to have better care and follow-up. For instance, identifying a Y chromosome can prevent the occurrence of a gonadoblastoma, as gonadectomy should be discussed. On the other hand, finding normal XX cells in a patient with a previous diagnosis of homogenous 45,X TS, may be psychologically helpful and relevant for gynaecological care.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was sought for the study. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

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.

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.

Dysgerminoma in a 10-Year Old with 45X/46XY Turner Syndrome Mosaicism

BACKGROUND

Turner syndrome is a genetic disorder resulting from the absence of or structural abnormality of one X chromosome. The presence of Y chromosome material in girls with Turner syndrome confers an increased risk of benign and malignant germ cell tumor and prophylactic bilateral gonadectomy is recommended.

CASE

A 10-year-old Turner mosaic syndrome (45X/46XY) patient underwent prophylactic gonadectomy after unremarkable preoperative pelvic imaging. Histopathology showed a streak right gonad, and left gonad with gonadoblastoma with limited degree of infiltrating germinoma.

SUMMARYAND CONCLUSION

Gonadoblastoma and dysgerminoma have been reported in girls with Turner mosaic who carry Y chromosome material. Prophylactic gonadectomy should be considered in these girls without delay.

Recognition and management of adults with Turner syndrome: From the transition of adolescence through the senior years

Turner syndrome is recognized now as a syndrome familiar not only to pediatricians and pediatric specialists, medical geneticists, adult endocrinologists, and cardiologists, but also increasingly to primary care providers, internal medicine specialists, obstetricians, and reproductive medicine specialists. In addition, the care of women with Turner syndrome may involve social services, and various educational and neuropsychologic therapies. This article focuses on the recognition and management of Turner syndrome from adolescents in transition, through adulthood, and into another transition as older women. It can be viewed as an interpretation of recent international guidelines, complementary to those recommendations, and in some instances, an update. An attempt was made to provide an international perspective. Finally, the women and families who live with Turner syndrome and who inspired several sections, are themselves part of the broad readership that may benefit from this review.

Detection of the SRY gene in patients with Turner Syndrome

BACKGROUND

If turner syndrome (TS) patients have a Y-containing cell line, they have an increased risk for gonadal tumors. TS patients are therefore screened for Y-chromosome and Y-specific sequences, such as SRY, DYZ1, DYZ3, DYS132, ZFY, TSPY, etc. In addition, since the dysgenetic gonad may include the stroma and granulosa/sertoli cells, which produce androgens, virilization can seen in girls with Y-chromosomal material. Prophylactic gonadectomy may therefore be required for optimal management in such patients. Our aim is to discuss our observations in the follow-up of TS patients.

METHODS

SRY was investigated in 71 out of 85 TS cases (aged 3 months-27 years) between 2005 and 2017. Fluorescent in situ hybridization (FISH) was used until 2014, after which SRY analysis was performed using the polymerase chain reaction (PCR) method. SRY analysis was performed a second time using PCR in 25 cases previously investigated with FISH.

RESULTS

We identified no positive cases. No pathological findings in terms of virilization, clitoromegaly, or posterior labial adhesions were also determined in our TS cases. Further studies were not required since no pathological findings also were detected at ultrasonography.

CONCLUSION

If Y-chromosome material has not been detected by conventional cytogenetic methods in TS patients with masculine features, further techniques should be applied to prevent the risk of invasive tumors, such as multiple sequences beside the Y centromere. This approach will prevent overtreatment.

Early Bilateral Gonadoblastoma in a Young Child with Mosaicism for Turner Syndrome and Trisomy 18 with Y Chromosome

Mosaic Turner syndrome (TSM) commonly occurs in the form of 45,X/46,XX and 45,X/46,X,i(X)(q10). Mosaicism for a Y chromosome, 45,X/46,XY, has been well documented and is associated with increased risk of gonadoblastoma (GB). To date, there are only six reported cases of TSM with a trisomy 18 karyotype, and only two of these were phenotypically female with 45,X/47,XY,+18 karyotype. We present the case of a phenotypically female infant born with dysmorphic features. G-banded karyotype and interphase FISH of blood showed 45,X in 95% and 47,XY,+18 (trisomy 18) in 5% of cells analysed. However, interphase FISH of buccal cells showed only the presence of the 45,X cell line. Due to the presence of Y chromosome material, elective gonadectomy was performed at 13 months of age. There were bilateral streak ovaries with early evidence of GB bilaterally, a rudimentary uterus and bilateral fallopian tubes with unilateral ectopic adrenal tissue identified histologically. Interphase FISH of the gonadal tissue was similar to the blood findings with 45,X in 86% of cells and 47,XY,+18 in 14% of cells analysed. This case highlights a rare karyotype of TSM and trisomy 18 in the same patient and is the first reporting the associated finding of bilateral GB.

Perspectives in Pediatric Pathology, Chapter 25. Testicular and Paratesticular Tumors in the Pediatric Age Group

Testicular tumors in the prepubertal age are relatively rare, representing only 9.4% of the total testicular and paratesticular specimens from a 20-year review performed at a large pediatric hospital [ 1 ]. They account for 1% to 2% of all solid tumors in the pediatric age group, with an annual incidence between 0.5/100 000 and 2/100 000 boys according to Coppes et al [ 2 ] and data from the Prepubertal Testicular Tumor Registry [ 3 ]. Similar to other neoplasms afflicting children, a bimodal age distribution is observed. The first peak is between birth and 3 years of age, and a second one occurs at the onset of puberty, extending to the fourth decade. Reports on their frequency vary because some investigators include the adolescent period, while others do not [ 4 ]. The vast majority of testicular tumors are germ cell neoplasms, accounting for 95% across all ages [ 5 ]. In children, germ cell tumors also predominate, representing 71% of all testicular neoplasms. These include yolk sac tumors (49%), teratomas (13%), seminomas and mixed germ cell tumors (9%), and sex-cord stromal tumors (29%). Malignant potential is significantly lower (less than 70%) in the pediatric age group compared to adults (90%) [ 6 ]. According to Pohl et al, 74% of prepubertal testicular tumors are benign [ 7 ].

Prevalence and Physical Distribution of SRY in the Gonads of a Woman with Turner Syndrome: Phenotypic Presentation, Tubal Formation, and Malignancy Risk

Although monosomy X is the most common karyotype in patients with Turner syndrome, the presence of Y chromosome material has been observed in about 10% of patients. Y chromosome material in patients with Turner syndrome poses an increased risk of gonadoblastoma and malignant transformation. We report a woman with a diagnosis of Turner syndrome at 12 years of age, without signs of virilization, and karyotype reported as 46,X,del(X)(q13). At 26 years, cytogenetic studies indicated the patient to be mosaic for monosomy X and a cell line that contained a du-plicated Yq chromosome. Bilateral gonadectomy was performed and revealed streak gonads, without evidence of gonadoblastoma. Histological analysis showed ovarian stromal cells with few primordial tubal structures. FISH performed on streak gonadal tissue showed a heterogeneous distribution of SRY, with exclusive localization to the primordial tubal structures. DNA extraction from the gonadal tissue showed a 6.5% prevalence of SRY by microarray analysis, contrasting the 86% prevalence in the peripheral blood sample. This indicates that the overall gonadal sex appears to be determined by the majority gonosome complement in gonadal tissue in cases of sex chromosome mosaicism. This case also raises questions regarding malignancy risk associated with Y prevalence and tubal structures in gonadal tissue.

Whole-Exome Sequencing for Diagnosis of Turner Syndrome: Toward Next-Generation Sequencing and Newborn Screening

CONTEXT

Turner syndrome (TS) is due to a complete or partial loss of an X chromosome in female patients and is not currently part of newborn screening (NBS). Diagnosis is often delayed, resulting in missed crucial diagnostic and therapeutic opportunities.

OBJECTIVES

This study sought to determine if whole-exome sequencing (WES) as part of a potential NBS program could be used to diagnose TS.

DESIGN, SETTING, PATIENTS

Karyotype, chromosomal microarray, and WES were performed on blood samples from women with TS (n = 27) enrolled in the Personalized Genomic Research study at the National Institutes of Health. Female control subjects (n = 37) and male subjects (n = 27) also underwent WES. Copy number variation was evaluated using EXCAVATOR2 and B allele frequency was calculated from informative single nucleotide polymorphisms. Simulated WES data were generated for detection of low-level mosaicism and complex structural chromosome abnormalities.

RESULTS

We detected monosomy for chromosome X in all 27 TS samples, including 1 mosaic for 45,X/46,XX and another with previously unreported material on chromosome Y. Sensitivity and specificity were both 100% for the diagnosis of TS with no false-positive or false-negative results. Using simulated WES data, we detected isochromosome Xq and low-level mosaicism as low as 5%.

CONCLUSION

We present an accurate method of diagnosing TS using WES, including cases with low-level mosaicism, isochromosome Xq, and cryptic Y-chromosome material. Given the potential use of next-generation sequencing for NBS in many different diseases and syndromes, we propose WES can be used as a screening test for TS in newborns.

Gonadoblastoma in patients with 45,X/46,XY mosaicism: A 16-year experience

BACKGROUND

It is recognised that individuals with a 45,X/46,XY karyotype, known as Turner mosaic syndrome with Y chromosome material (TMSY), have an increased risk of developing gonadoblastoma (GB), which may then devolve into one of a number of germ cell malignancies. Hence, children with TMSY are usually recommended to undergo prophylactic gonadectomy.

OBJECTIVE

We designed this study to describe the phenotypic features of our series of children with TMSY who underwent prophylactic gonadectomy in order to evaluate the prevalence of GB and germ cell malignancies in their resected specimens.

STUDY DESIGN

This is a retrospective case series wherein we comprehensively reviewed the clinical, histological, and cytogenetic features of all patients who underwent prophylactic gonadectomy at three tertiary paediatric referral centres over 16 years. Cases were identified from surgical logbooks and through the institutional histopathology database. Data were collected with particular reference to clinical phenotype, predominant karyotype cell line, operative management, anatomical findings and the presence of neoplastic changes.

RESULTS

Fourteen children ranging in age at the time of surgery from 2 weeks to 17 years were included in the series. Eleven children were reared as females. The three children who were reared as males had severe penoscrotal hypospadias. The 46,XY cell line was the predominant cell line in seven (50%) cases in blood lymphocytes. The resected specimens from four patients (28.6%) contained GB, with three patients having bilateral GB. This sub-group of patients with GB were aged 5 months, 48 months, 71 months, and 13 years. GB arose in one patient with and three patients without genital virilisation. There was no focus of invasive germ cell tumour in any specimen.

DISCUSSION

GB may be present in infants with TMSY as young as 5 months, even with low levels of Y chromosome material. The prevalence of GB in prophylactic gonadectomy specimens is similar to many previously reported series, although the absence of dysgerminoma in our series is reassuring. The exclusive presence of GB in intra-abdominal gonads is in keeping with the findings of several other series.

CONCLUSION

Owing to the presence of gonadoblastoma in the gonads of children with TMSY as young as 5 months, we recommend that all patients with intra-abdominal gonads in the context of TMSY should duly undergo prophylactic gonadectomy, although the timing of such surgery can be discussed with parents during counselling regarding the risk of malignancy.

Tumor risk of children with 45,X/46,XY gonadal dysgenesis in relation to their clinical presentations: Further insights into the gonadal management

OBJECTIVE

To investigate the risk of gonadal germ cell neoplasms (GCN) in children with 45,X/46,XY gonadal dysgenesis and its relation to the clinical presentations.

METHODS

We conducted a retrospective study reviewing the clinical and gonadal features of all consecutive children with 45,X/46,XY gonadal dysgenesis who received gonadal management in a tertiary center from 1985 to 2015. Study subjects were divided into Group I(significant genitalia anomaly), Group II(female phenotype) and Group III(male phenotype).

RESULTS

21 children were studied (Group I=8; Group II=11; Group III=2). All 19 children of Group I and II eventually underwent bilateral gonadectomy. One patient of Group III underwent gonadal biopsy which showed increase in fibrous tissue in the testes without any GCN. 3/8(37.5%) and 6/11(54.5%) of patients in Group I and II respectively had either gonadoblastoma (GB) or carcinoma-in-situ (CIS) or both affecting one or both gonads. Among Group I patients, the 4 dysgenetic testes affected by CIS in 3 patients were intraabdominal (n=1), inguinal (n=1) and scrotal (n=2) in positions. Among Group II patients, 6/20 streak gonads had GB and 2/2 dysgenetic testes had GB or CIS.

CONCLUSIONS

45,X/46,XY children with significant genitalia anomaly or female phenotype are both at high risk of gonadal GCN.

Identification of Y-Chromosome Sequences in Turner Syndrome

OBJECTIVES

To investigate the presence of Y-chromosome sequences and determine their frequency in patients with Turner syndrome.

METHODS

The study included 23 patients with Turner syndrome from Brazil, who gave written informed consent for participating in the study. Cytogenetic analyses were performed in peripheral blood lymphocytes, with 100 metaphases per patient. Genomic DNA was also extracted from peripheral blood lymphocytes, and gene sequences DYZ1, DYZ3, ZFY and SRY were amplified by Polymerase Chain Reaction.

RESULTS

The cytogenetic analysis showed a 45,X karyotype in 9 patients (39.2 %) and a mosaic pattern in 14 (60.8 %). In 8.7 % (2 out of 23) of the patients, Y-chromosome sequences were found. This prevalence is very similar to those reported previously. The initial karyotype analysis of these patients did not reveal Y-chromosome material, but they were found positive for Y-specific sequences in the lymphocyte DNA analysis.

CONCLUSION

The PCR technique showed that 2 (8.7 %) of the patients with Turner syndrome had Y-chromosome sequences, both presenting marker chromosomes on cytogenetic analysis.

Neoplasia in Turner syndrome. The importance of clinical and screening practices during follow-up

AIM OF THE STUDY

Turmer syndrome (TS) patients show increased morbidity due to metabolic, autoimmune and cardiovascular disorders. A risk of neoplasia is also reported. Here, we review the prevalence of neoplasia in a cohort of Turner patients.

METHODS

We retrospectively evaluated 87 TS women. Follow-up included periodic ultrasound of the neck, abdominal and pelvic organs, dermatologic evaluation and fecal occult blood test. Karyotype was 45,X in 46 patients. During follow-up, 63 girls were treated with growth hormone, 65 with estro-progestin replacement therapy and 20 with L-thyroxine. Autoimmune diseases were present in 29 TS.

RESULTS

A total of 17 neoplasms in 14 out of 87 patients were found. Six skin neoplasia, 3 central nervous system tumors, 3 gonadal neoplasia, 2 breast tumors, 1 hepatocarcinoma, 1 carcinoma of the pancreas and 1 follicular thyroid cancer were detected. Age at tumor diagnosis was higher in 45,X pts than in those with other karyotypes (p = 0.003). Adenomioma gallbladdder (AG) was detected in 15.3% of the patients, with a lower age in girls at diagnosis with an associated neoplasia in comparison with TS without tumors (p = 0.017). No correlation between genetic make up, treatment, associated autoimmune diseases and neoplastia was found.

CONCLUSION

In our TS population an increased neoplasia prevalence was reported. A high prevalence of AG was also noted and it might be indicative of a predisposition to neoplasia. Further studies are needed to define the overall risk for neoplasia, and to determine the role of the loss of the X-chromosome and hormonal therapies.

[Prevalence of Y-chromosome sequences and gonadoblastoma in Turner syndrome]

OBJECTIVE

To assess the prevalence of Y-chromosome sequences and gonadoblastoma in patients with Turner syndrome using molecular techniques.

DATA SOURCE

A literature search was performed in Pubmed, limiting the period of time to the years 2005 to 2014 and using the descriptors: Turner syndrome and Y sequences (n=26), and Turner syndrome and Y-chromosome material (n=27). The inclusion criteria were: articles directly related to the subject and published in English or Portuguese. Articles which did not meet these criteria and review articles were excluded. After applying these criteria, 14 papers were left.

DATA SYNTHESIS

the main results regarding the prevalence of Y-chromosome sequences in Turner syndrome were: 1-about 60% of the studies were conducted by Brazilian researchers; 2-the prevalence varied from 4.6 to 60%; 3-the most frequently investigated genes were SRY, DYZ3 and TSPY; 4-seven studies used only PCR, while in the remaining seven it was associated with FISH. Nine of the 14 studies reported gonadectomy and gonadoblastoma. The highest prevalence of gonadoblastoma (33%) was found in two studies. In five out of the nine papers evaluated the prevalence of gonadoblastoma was 10 to 25%; in two of them it was zero.

CONCLUSIONS

according to these data, molecular analysis to detect Y-chromosome sequences in TS patients is indicated, regardless of their karyotype. In patients who test positive for these sequences, gonadoblastoma needs to be investigated.

Y chromosome in Turner syndrome: detection of hidden mosaicism and the report of a rare X;Y translocation case

Turner syndrome (TS) is a common genetic disorder in females associated with the absence of complete or parts of a second sex chromosome. In 5-12% of patients, mosaicism for a cell line with a normal or structurally abnormal Y chromosome is identified. The presence of Y-chromosome material is of medical importance because it results in an increased risk of developing gonadal tumours and virilisation. Molecular study and fluorescence in situ hybridisation approaches were used to study 74 Brazilian TS patients in order to determine the frequency of hidden Y-chromosome mosaicism, and to infer the potential risk of developing malignancies. Additionally, we describe one TS girl with a very uncommon karyotype 46,X,der(X)t(X;Y)(p22.3?2;q11.23) comprising a partial monosomy of Xp22.3?2 together with a partial monosomy of Yq11.23. The presence of cryptic Y-chromosome-specific sequences was detected in 2.7% of the cases. All patients with Y-chromosome-positive sequences showed normal female genitalia with no signs of virilisation. Indeed, the clinical data from Y-chromosome-positive patients was very similar to those with Y-negative results. Therefore, we recommend that the search for hidden Y-chromosome mosaicism should be carried out in all TS cases and not be limited to virilised patients or carriers of a specific karyotype.

Occurrence of Gonadoblastoma in Patients with 45,X/46,XY Mosaicism

STUDY OBJECTIVE

To estimate the overall frequency of gonadal tumors in patients with 45,X/46,XY mosaicism who underwent gonadectomy and to determine whether the degree of external masculinization or the location of gonads were associated with the presence of gonadal tumor.

DESIGN

Retrospective study of patients with karyotype of 45,X/46,XY or variant who received care at the study institution between 1995 and 2012.

SETTING

University of Michigan Health System (Ann Arbor, Michigan), a tertiary care academic center.

PARTICIPANTS

Sixteen patients with karyotype of 45,X/46,XY who underwent gonadectomy.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

Presence of pathology-confirmed gonadal tumor.

RESULTS

In patients who underwent bilateral gonadectomy, gonadoblastomas were detected in 36.4% (4 of 11), and all were identified in patients with normal female external genitalia (4 of 8 [50.0%]). Abdominal gonads were associated with a nonsignificant increase in rate of gonadal tumor compared with inguinal or scrotal gonads. No malignant tumors were identified.

CONCLUSION

The overall rate of gonadoblastoma was higher than previously reported. The high rate of gonadoblastoma in patients with female external genitalia and the lack of gonadal function support continuing the standard of care of practice of prophylactic gonadectomy in this patient population.

Oophorectomy versus salpingo-oophorectomy in Turner syndrome patients with Y-chromosome material: clinical experience and current practice patterns assessment

BACKGROUND/PURPOSE

Gonadectomy is recommended in Turner syndrome (TS) patients with Y-chromosome material due to high risk of tumor in the dysgenetic gonads. No recommendations exist on whether concurrent salpingectomy should be performed.

METHODS

A retrospective chart review of surgical procedure and histopathology in TS patients with Y-chromosome enrolled in a TS database was undertaken at Cincinnati Children's Hospital Medical Center. An electronic survey was sent to members of the International Pediatric Endosurgery Group to assess prevalent practice patterns and attitudes on gonadectomy and concurrent salpingectomy in this population.

RESULTS

In March 2011, 12/158 (8%) TS girls (mean age 6.6 years) enrolled in the database had TS with Y-chromosome. Gonadoblastoma was identified in 4/12 (33%) patients and 2/4 had malignant transformation to dysgerminoma and teratoma. Approach to gonadectomy was varied and 3/12 had concurrent salpingectomy. Fifty-four laparoscopic surgeons responded to the survey with no clear consensus on whether salpingectomy should be concurrently performed.

CONCLUSIONS

TS patients with Y-chromosome have an increased risk of gonadal tumor development and gonadectomy is recommended. While there is no consensus among pediatric laparoscopic surgeons on concurrent salpingectomy, it is reasonable to consider this combination procedure.

Current controversies in turner syndrome: Genetic testing, assisted reproduction, and cardiovascular risks

Patients with Turner syndrome (TS) require close medical follow-up and management for cardiac abnormalities, growth and reproductive issues. This review summarizes current controversies in this condition, including: 1) the optimal genetic testing for Turner syndrome patients, particularly with respect to identification of Y chromosome material that may increase the patient's risk of gonadoblastoma and dysgerminoma, 2) which patients should be referred for bilateral gonadectomy and the recommended timing of such referral, 3) options for assisted reproduction in these patients and associated risks, 4) the increased risk of mortality associated with pregnancy in this population, and 5) how best to assess and monitor cardiovascular risks.

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.

Buccal cell FISH and blood PCR-Y detect high rates of X chromosomal mosaicism and Y chromosomal derivatives in patients with Turner syndrome

Turner syndrome (TS) is the result of (partial) X chromosome monosomy. In general, the diagnosis is based on karyotyping of 30 blood lymphocytes. This technique, however, does not rule out tissue mosaicism or low grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome. We investigated different approaches to improve the detection of mosaicisms in 162 adult women with TS (mean age 29.9 ± 10.3). Standard karyotyping identified 75 patients (46.3%) with a non-mosaic monosomy 45,X. Of these 75 patients, 63 underwent additional investigations including FISH on buccal cells with X- and Y-specific probes and PCR-Y on blood. FISH analysis of buccal cells revealed a mosaicism in 19 of the 63 patients (30.2%). In five patients the additional cell lines contained a (derivative) Y chromosome. With sensitive real-time PCR we confirmed the presence of this Y chromosome in blood in three of the five cases. Although Y chromosome material was established in ovarian tissue in two patients, no gonadoblastoma was found. Our results confirm the notion that TS patients with 45,X on conventional karyotyping often have tissue specific mosaicisms, some of which include a Y chromosome. Although further investigations are needed to estimate the risk of gonadoblastoma in patients with Y chromosome material in buccal cells, we conclude that FISH or real-time PCR on buccal cells should be considered in TS patients with 45,X on standard karyotyping.

Update on Turner and Noonan syndromes

Turner syndrome (TS) and Noonan syndrome (NS) have short stature as a constant feature; however, both conditions can present clinicians with a challenging array of genetic, cardiovascular, developmental, and psychosocial issues. In recent years, important advances have been achieved in each of these areas. This article reviews these two syndromes and provides updates on recent developments in diagnostic evaluation, growth and development, psychological issues, and treatment options for patients with TS and NS.

Molecular detection of cryptic Y-chromosomal material in patients with Turner syndrome

A systematic search for a hidden Y-chromosome mosaicism, in Turner syndrome (TS) patients is justified by the evaluation of the risk of development of germ cell tumors. In this study, we analyzed cryptic Y-chromosome derivatives by polymerase chain reaction (PCR) coupled with fluorescence in situ hybridization (FISH) using Y-specific sequences in patients with TS, and validated this methodology. Unrelated patients with TS (n=32) of Mexican mestizo ethnic origin were diagnosed using cytogenetic analysis. Clinical assessment, endocrine evaluation, karyotyping, FISH and PCR analysis of the Y-chromosomal loci were performed. We found that 9.4% (3 out of 32) patients with TS had Y-chromosome material. Two patients showed Y-chromosome by conventional cytogenetics. One patient had no Y-chromosome by initial karyotyping (45, X) but was positive by lymphocyte PCR DNA analysis of the Y-sequence-specific sex-determining region Y (SRY) gene. Our results suggest that the detection of the Y-chromosome material using sensitive methods, such as PCR coupled with FISH, should be carried out in all patients with TS and should not be limited to TS patients with cytogenetically identifiable Y-chromosome and/or virilization.

[The inclusion of new techniques of chromosome analysis has improved the cytogenetic profile of Turner syndrome]

OBJECTIVE

To evaluate the effect of the improvement of chromosome analysis on the cytogenetic findings of Turner syndrome (TS) patients.

METHODS

Retrospective study of the results of the karyotypes of 260 patients with TS, regarding banding techniques, number of cells analyzed and results of investigation of Y-chromosome sequences. According to karyotype, divided in 45,X; sex chromosome mosaicism without Y; structural aberrations of sex chromosomes with or without mosaicism; sex chromosome mosaicism with Y.

RESULTS

45,X was the most frequent karyotype (108), followed by structural aberrations (88) and mosaics (58 without Y and 6 with Y). Introduction of banding techniques and increase in the number of cells analyzed resulted in progressive decrease of 45,X karyotype and increase of structural aberrations. The study of Y-chromosome sequences was performed in 96 cases of which 10 resulted positive.

CONCLUSIONS

Improvement of chromosome analysis over the years has modified the cytogenetic profile of TS.

Y-chromosome markers in Turner syndrome: Screening of 130 patients

BACKGROUND

The presence of Y-chromosome material in patients with Turner syndrome (TS) is a risk factor for the development of gonadoblastoma. Cytogenetic analysis detects Y-chromosome mosaicism in about 5% of Turner patients. However, if Y-chromosome sequences are present in only a few cells, they may be missed by routine analysis. The use of molecular techniques to detect the presence of Y-chromosome fragments in such patients is becoming increasingly important.

AIM

The objective of our study was to analyze cryptic Y-chromosome derivatives in Hungarian TS patient population by real-time PCR (RT-PCR).

SUBJECTS AND METHODS

Cytogenetic and RT-PCR methods were used to examine peripheral blood DNA of 130 Hungarian patients with TS for the presence of Y-chromosome. With RT-PCR, 4 regions throughout the Y-chromosome were analyzed.

RESULTS

Initial cytogenetic karyotyping assessing 10-50 metaphases revealed 3 patients with Y-chromosome positivity. RT-PCR revealed further 6 patients with Y-chromosome, who were initially considered as Y-negatives by standard kayotyping. The consecutive cytogenetic analysis of a large number (about 100) of metaphases (in 5 patients) and/or FISH (in 6 patients) however, also confirmed the presence of the Y-chromosome in these patients. Prophylactic gonadectomy was carried out in all 9 patients and 1 of them was diagnosed as having bilateral gonadoblastoma without clinical symptoms.

CONCLUSIONS

We recommend a routine molecular screening for hidden Y-chromosome sequences in Turner patients, who are negative for Y-chromosome by conventional cytogenetic analysis, in order to calculate the future risk of developing gonadoblastoma.

Approach to the patient with Turner syndrome

Turner syndrome (TS) occurs in about 1:4000 live births and describes females with a broad constellation of problems associated with loss of an entire sex chromosome or a portion of the X chromosome containing the tip of its short arm. TS is associated with an astounding array of potential abnormalities, most of them thought to be caused by haploinsufficiency of genes that are normally expressed by both X chromosomes. A health care checklist is provided that suggests screening tests at specific ages and intervals for problems such as strabismus, hearing loss, and autoimmune thyroid disease. Four areas of major concern in TS are discussed: growth failure, cardiovascular disease, gonadal failure, and learning disabilities. GH therapy should generally begin as soon as growth failure occurs, allowing for rapid normalization of height. Cardiac imaging, preferably magnetic resonance imaging, should be performed at diagnosis and repeated at 5- to 10-yr intervals to assess for congenital heart abnormalities and the emergence of aortic dilatation, a precursor to aortic dissection. Hypertension should be aggressively treated. For those with gonadal dysgenesis, hormonal replacement therapy should begin at a normal pubertal age and be continued until the age of 50 yr. Transdermal estradiol provides the most physiological replacement. Finally, nonverbal learning disabilities marked by deficits in visual-spatial-organizational skills, complex psychomotor skills, and social skills are common in TS. Neuropsychological testing should be routine and families given support in obtaining appropriate therapy, including special accommodations at school.

Morphology and immunophenotyping of a monolateral ovotestis in a 46,XderY/45,X mosaic individual with ambiguous genitalia

Disorders of sexual development represent a pathologic and clinical challenge. Many different clinical syndromes exist, and several classifications have been proposed in relation to different risks for malignant degeneration. The morphology, cytogenetics, and immunophenotype of a monolateral ovotestis in a 3-month-old individual with ambiguous genitalia and right inguinal mass are reported. The inguinal mass consisted of a tiny female genital tract with a hermaphroditic gonad with focal placental-like alkaline phosphatase-stained gonocytes; chromosome analysis disclosed a mosaic constitution: 46,XderY/45,X with a rearranged Y chromosome. A sharp morphologic distinction between true hermaphroditism and mixed gonadal dysgenesis probably does not exist, and cytogenetic characterization is mandatory. The presence of placental-like alkaline phosphatase-stained gonocytes indicates a high risk of malignant transformation, and justifies the surgical removal of the dysgenetic gonad. Fertility is unlikely.

Insights into selected genetic diseases affecting the female reproductive tract and their implication for pathologic evaluation of gynecologic specimens

CONTEXT

Recent advances in the understanding of genetic conditions involving the female genital tract and mechanisms of carcinogenesis in this setting affect patient management and thus necessitate appropriate pathologic evaluation of specimens. In the past, specimens from prophylactic surgery were a rarity; however, they are now more frequently encountered and often require a significant variation from routine processing methods. Pathologists also receive more specimens requiring prospective workup for possible underlying genetic conditions such as microsatellite instability.

OBJECTIVE

To summarize the current knowledge of important genetic and hereditary conditions affecting the female reproductive organs while highlighting the resulting practical significance for specimen handling, "grossing," and microscopic evaluation in gynecologic pathology.

DATA SOURCES

This update is based on a review of recent peer-reviewed literature and the experience with cases at the parent institutions.

CONCLUSIONS

Gynecologic specimens received from patients with certain genetic conditions require specific clinicopathologic knowledge for appropriate pathologic examination. The evaluation of prophylactic resection specimens focuses on the detection of cancer precursors and possible occult disease, which may require a more thorough and detailed examination than an obvious carcinoma. Standardized protocols for handling prophylactic gynecologic resection specimens are available for some, but not all, types of specimens. The prospective evaluation of a gynecologic pathology specimen for potential genetic conditions such as microsatellite instability is a very recent subject. Currently, well-established protocols are not available; however, as clinical and prognostic significance has become more clearly elucidated, familiarity with this evolving field is increasingly important to properly assess these pathologic specimens.

Molecular identification of chromosome Y sequences in Brazilian patients with Turner syndrome

The investigation of Y-specific sequences in patients with Turner Syndrome (TS) with karyotype 45,X or mosaic, has a fundamental role in the clinical management of these patients. The relationship between the presence of Y chromosome fragments and a higher risk of gonadoblastoma in TS has already been established. The aim of the study was to investigate the presence of Y-chromosome fragments in a population of 42 female Brazilian patients with TS from Mato Grosso state. Cytogenetic analysis has shown the karyotypes 45,X in 27 of them (64.3%) and mosaic in 15 (35.7%). The presence of the Y-primers SRY, DYZ3, ZFY, DYZ1, DYS1 and PABY was investigated in all patients. These markers were amplified by polymerase chain reaction (PCR) technique, using DNA genomic from peripheral blood lymphocytes. None of these patients had shown any Y-chromosome fragments when they were analysed only by the classic cytogenetic technique. The PCR analysis with the Y-specific sequences ZFY and DYZ3 were identified in two different patients (4.8%), both with karyotype 45,X. It was concluded that PCR is efficient in the investigation of hidden Y-fragments in TS patients. Therefore, this method should be included in the routine assistance of these patients.

Mosaicism for r(X) and der(X)del(X)(p11.23)dup(X)(p11.21p11.22) provides insight into the possible mechanism of rearrangement

We report a patient with a unique and complex cytogenetic abnormality involving mosaicism for a small ring X and deleted Xp derivative chromosome with tandem duplication at the break point. The patient presented with failure to thrive, muscular hypotonia, and minor facial anatomic anomalies, all concerning for Turner syndrome. Brain MRI revealed mild thinning of the corpus callosum, an apparent decrease in ventricular white matter volume, and an asymmetric myelination pattern. Array comparative genome hybridization analysis revealed mosaicism for the X chromosome, deletion of the short arm of an X chromosome, and a duplication of chromosome region Xp11.21-p11.22. G-banded chromosome and FISH analyses revealed three abnormal cell lines: 46,X,der(X)del(X)(p11.23)dup(X)(p11.21p11.22)/46,X,r(X)(q11.1q13.1)/45,X. The small ring X chromosome was estimated to be 5.2 Mb in size and encompassed the centromere and Xq pericentromeric region. X chromosome inactivation (XCI) studies demonstrated a skewed pattern suggesting that the ring X remained active, likely contributing to the observed clinical features of brain dysmyelination. We hypothesize that a prezygotic asymmetric crossing over within a loop formed during meiosis in an X chromosome with a paracentric inversion resulted in an intermediate dicentric chromosome. An uneven breakage of the dicentric chromosome in the early postzygotic period might have resulted in the formation of one cell line with the X chromosome carrying a terminal deletion and pericentromeric duplication of the short arm and the second cell line with the X chromosome carrying a complete deletion of Xp. The cell line carrying the deletion of Xp could have then stabilized through self-circularization and formation of the ring X chromosome.

Recent Advances in the Pathology and Classification of Gonadal Neoplasms Composed of Germ Cells and Sex Cord Derivatives

In recent years, our understanding of neoplasms composed of germ cells and sex cord derivatives has increased. In this review, advances in the classification and pathology of ovarian germ cell-sex cord-stromal tumors are discussed. Only 2 neoplasms, each with a distinctive pathogenesis and clinicopathologic features, are included in this category. Gonadoblastoma is a tumor that usually occurs in the dysgenetic gonads of intersex patients that have a Y chromosome, whereas mixed germ cell-sex cord-stromal tumor arises in normal gonads in patients without sex chromosomal abnormalities. Ovarian mixed germ cell-sex cord-stromal tumors differ from their testicular counterparts in their histological appearance, immunohistochemical staining reactions, and biological behavior probably because the latter show a greater degree of maturity of their germ cell component. The introduction of cisplatin-based chemotherapy and the application of tumor markers have dramatically improved the clinical outlook for those patients who develop secondary malignant germ cell neoplasms.

Detection of Y chromosomal material in patients with a 45,X karyotype by PCR method

A 45,X karyotype is one of the common chromosomal abnormalities characterized by short stature, lack of development of secondary sexual characteristics, webbed neck and cubitus valgus. This phenotype was described by Turner in 1938 and was called Turner syndrome (TS). About 40-60% of the patients with TS phenotype have a 45,X karyotype, the rest either have a structurally abnormal X or Y chromosome or mosaicism with a second cell line. Determination of Y chromosome derivatives in patients with a 45,X karyotype is important for the management of these patients due to increased risk of gonadoblastoma. Low level mosaicism of Y chromosome may be missed by cytogenetic methods. The aim of our study is to analyze cryptic Y chromosome derivatives using Y specific sequences in 40 Turkish patients with a pure 45,X karyotype. Fourteen different Y specific sequences along the Y chromosome were selected for the detection of cryptic Y chromosome material by PCR analysis. The present study demonstrated that 2 patients with a 45,X karyotype (5%) have Y specific sequences except sex related region Y (SRY). One of them had displayed enhanced virilisation whereas other showed no virilisation. In conclusion, it has been found by PCR analysis that 5% of patients with a 45,X karyotype have Y chromosome sequences in the absence of any marker chromosome by cytogenetic analysis. The data also suggest that the patients with a 45,X karyotype should be analyzed for the presence of Y chromosome derivatives by sensitive methods, such as PCR, in order to calculate the future risk of developing gonadoblastoma.

The Y-encoded TSPY protein: a significant marker potentially plays a role in the pathogenesis of testicular germ cell tumors

The testis-specific protein Y-encoded (TSPY) gene is the putative gene for the gonadoblastoma locus on the Y chromosome (GBY) that predisposes dysgenetic gonads of intersex patients to gonadoblastoma development. TSPY is expressed at high levels in gonadoblastoma tissues, supporting its possible oncogenic function in this type of germ cell tumors. To explore the possibility that this Y chromosome gene is also involved in pathogenesis of the more common testicular germ cell tumors (TGCTs), we have conducted various expression studies using immunohistochemistry, Western blotting, and reverse transcription-polymerase chain reaction analysis on 171 cases of TGCTs and selected normal testis controls. Our results demonstrated that TSPY protein is abundantly expressed in the precursor, carcinoma in situ or intratubular germ cell neoplasia unclassified, and seminoma, but only minimally or not expressed in various types of nonseminomas. TSPY coexpresses with established germ cell tumor markers (such as placental-like alkaline phosphatase, c-KIT, OCT4) and proliferative markers (such as Ki-67 and cyclin B1) in the same tumor cells at both RNA and protein levels. Ectopic TSPY expression in cultured cells up-regulates progrowth genes, including those at chromosome 12p13, frequently gained/amplified in TGCTs. Our results suggest that TSPY, in combination with other markers, could be an important marker for diagnosis and subclassification of TGCTs and support its role in the pathogenesis of both gonadoblastoma and TGCTs.

Testis-specific protein Y-encoded gene is expressed in early and late stages of gonadoblastoma and testicular carcinoma in situ

The testis-specific protein Y-encoded gene (TSPY) is a tandem repeat gene located at the critical region for the gonadoblastoma locus on Y chromosome that predisposes the dysgenetic gonads of intersex individuals to oncogenesis. The expression and molecular properties of TSPY suggest that it is the putative gene for the gonadoblastoma locus on Y chromosome. In this study, we examined the expression of TSPY and other germ cell tumor markers in 4 cases of gonadoblastoma using immunostaining techniques. Our results showed that TSPY expression was closely associated with initiation and various stages of gonadoblastoma development. TSPY protein localized with established germ cell tumor markers, such as the placental alkaline phosphatase, c-KIT, and OCT3/4, in the same tumor cells of both gonadoblastoma and adjacent carcinoma in situ, the precursor for germ cell tumors. These findings support the candidacy of TSPY as the gene for the gonadoblastoma locus on Y chromosome and suggest that TSPY could be a significant marker for these types of germ cell tumors.

Neoplasms and pathology of sexual developmental disorders (intersex)

Continuing new insights into the biology of sexual development and advances in chromosome analysis have led to early identification and prompt treatment of the intersexual patient, the results of which facilitate a more normal life for affected individuals. Based on these advances, a classification of abnormal sexual development has been developed and refined that correlates the gonadal and genital anatomy with the chromosomal findings and specific genetic or metabolic defects. In a shift from a classification anchored on whether the intersex revolves about a specific gene or whole chromosomal abnormality, the current classification is organised by broader categories into which the intersexual disorders are divided into 'abnormalities of genital differentiation', due largely to the abnormal production or sensitivity of a single hormone, or 'abnormalities in sex determination', due to abnormal gonadal differentiation, usually testicular, with or without chromosomal aberration. The current classification is an integrated approach to this complex group of disorders and is organised according to the manner by which patients present as well as on the pathophysiological basis of the defect. The classification also groups patients who are at high risk for development of gonadal neoplasia.