Bilateral seminomas in a 45X/46XY mosaic with Turner's phenotype: an unusual case of mixed gonadal dysgenesis

Gonadoblastoma in a patient with 45,X/46XY mosaicism

45,X/46,XY mosaicism is a sex development disorder with an estimated incidence of less than 1 in 15,000 live births. Various studies have shown there is an increased risk of germ cell tumours forming in Mosaic Turner syndrome. This includes gonadoblastoma, a clinically benign mixed germ-stromal cell tumour. However, this can later develop into one or several malignant germ cell neoplasms, for which early prophylactic gonadectomy is often recommended in patients with 45,X/46,XY mosaicism. The study presents the case of an 11-year-old patient diagnosed with a Mosaic Turner syndrome karyotype, who underwent prophylactic bilateral gonadectomy.

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.

[Azoospermia and 45,X/46,XY chromosomal mosaicism: a case report]

Chromosomal abnormalities are common in patients with oligozoospermia or azoospermia. We report the case of a 32-year patient, with male phenotype, and without hormonal or morphological abnormalities, with a severely reduced spermatogenesis. It was revealed a 45,X/46,XY gonadal dysgenesis. We have reviewed the various problems inherent in the discovery of this rare gonadal dysgenesis, including genetic, cancer and fertility risks.

Ectopically located gonads in a patient with mixed gonadal dysgenesis: detection by diffusion-weighted MRI

We report a case of mixed gonadal dysgenesis in which diffusion-weighted magnetic resonance imaging played a major role in the detection of ectopically located gonads. Magnetic resonance imaging may have a potential in detecting ectopically located gonads and may provide important information for the management of patients with mixed gonadal dysgenesis.