ESPE Abstracts

Introduction: Testicular regression syndrome (TRS) also called vanishing testes syndrome is a rare developmental disorder that represents less than 5% of cryptorchidism cases. It is characterized by the absence of one or both testicles with partial or complete absence of testicular tissue. TRS phenotypes are various depending on the extent and timing of the intrauterine accident during fetal sexual development.

Material and Methods: Our study will concern 4 cases of TRS treated in Mohamed VI universitary hospital between 2015 and 2019.

The mean age at diagnosis was 41 months (2 months - 11 years). Clinical examination noted bilateral cryptorchidism in all ours patients, 3 of them presented with micropenis and only one had gynecomastia. All our patients carried a male karyotype (46XY). The average AMH and testostérone values were respectively 2.4 ng/ml and 0.12 ng/ml. Pelvic ultrasound and pelvic MRI findings showed total absence of testicular tissues in three cases, while one of them presented a hypotrophic unilateral testicle. Three patients had an exploratory laparoscopy with a benign pathological study and all of them were treated by androgen replacement therapy and were followed up in our department.

Discussion/Conclusion: The descent of the testes appears to be under the control of several hormonal and mechanical factors, but no specific factor has yet been identified for the pathogenesis of undescended or non palpable testis. TRS is thought to be the result of late antenatal or perinatal vascular thrombosis or torsion or more unlikely an endocrinopathy.

Theoretically, TRS carries a potential for malignant degeneration in the long term outcome and therefore removal of any remnant tissue is a common practice to eliminate this risk. However, no case series has reported germinal dysplasia or intratubular germ cell neoplasia in any of the specimens taken from these patients and there is still controversy regarding the optimal management of the testicular remnant in cases of TRS. Reason why the management of TRS cases has to be discussed in multidisciplinary concertation meetings.