Ovary
Gonadal dysgenesis
Gonadal dysgenesis-general
Author: Mohiedean Ghofrani, M.D.
Last author update: 1 November 2011
Last staff update: 14 October 2020
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Gonadal dysgenesis [title] ovary
Table of Contents
Definition / general | Terminology | Etiology | Clinical features | Prognostic factors | Treatment | Molecular / cytogenetics descriptionCite this page: Ghofrani M Gonadal dysgenesis-general. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/ovarynontumorgonadaldysgenesis.html. Accessed June 5th, 2023.
Definition / general
- Disorder of sex development (DSD) in which one or both gonad(s) is / are undeveloped (streak gonad)
- Disorders of sex development are either female pseudohermaphroditism (46XX with 2 ovaries), male pseudohermaphroditism (46XY with two testes), true hermaphroditism (ovotestis present) or gonadal dysgenesis (either pure with normal 46XX or 46XY chromosomes and bilateral streak gonads or mixed with streak gonad)
Terminology
- Pure gonadal dysgenesis (PGD): both gonads are streak gonads (i.e. dysfunctional gonads without germ cells)
- Mixed gonadal dysgenesis (MGD): patient has a testis on one side and a streak gonad on the other
Etiology
- Chromosomal abnormality: may be 46XX, 46XY or 45XO
Clinical features
- Patients with pure gonadal dysgenesis have underdeveloped Müllerian organs (sexual infantilism), sometimes with clitoromegaly, while patients with mixed gonadal dysgenesis have ambiguous or female genitalia
- 46XX and 46XY patients present with primary amenorrhea and delayed secondary sexual development; 45XO present with typical Turner syndrome features
Prognostic factors
- Patients with pure gonadal dysgenesis are raised as female since there is no sexual ambiguity at birth; however, gender assignment in patients with mixed gonadal dysgenesis is variable and depends on the degree of virilization
- Approximately 20% of patients with gonadal dysgenesis develop a gonadal neoplasm within the first two decades of life, usually gonadoblastoma; almost all cases of gonadoblastoma have been reported in patients with pure or mixed gonadal dysgenesis or male pseudohermaphroditism
- Other neoplasms include seminomatous germ cell tumors such as seminoma and dysgerminoma, nonseminomatous germ cell tumors such as embryonal carcinoma and choriocarcinoma, as well as nongerm cell tumors such as Wilms tumor
Treatment
- Given the higher risk of malignancy in dysgenetic gonads, early surgical removal is indicated
Molecular / cytogenetics description
- Pure gonadal dysgenesis: 46XX, 46XY or 45XO
- Mixed gonadal dysgenesis: 45XY / 45XO (mosaic)
