Metastatic Mixed Germ Cell Tumour in a Patient with Cryptorchidism and Persistent Müllerian Duct Syndrome

Persistent Müllerian duct syndrome (PMDS) is a rare disorder of sexual development characterized by the persistence of Müllerian structures, such as the uterus and fallopian tubes, in phenotypically and genotypically normal males. It is usually identified during surgical interventions for cryptorchidism or inguinal hernias, and rarely during cancer of the ectopic testis.

We present the case of a 32-year-old male with a history of right cryptorchidism and hypospadias who presented with a metastatic germ cell tumour of the testis. Following systemic chemotherapy, the patient underwent midline laparotomy to remove all residual tumours. During the surgery, PMDS was unexpectedly diagnosed. Postoperative karyotyping confirmed a 46, XY genotype with a pathogenic defect in the anti-Müllerian hormone type II receptor (AMHR-II).

Interestingly, germ cell tumours have been reported in up to 33% of patients with PMDS, suggesting that the syndrome may confer an elevated risk of malignant transformation beyond that attributable to cryptorchidism alone. This case highlights the significant clinical association between PMDS and testicular germ cell tumours.

This case emphasizes that clinicians should consider underlying PMDS when cryptorchidism is accompanied by additional anomalies, such as hypospadias, particularly in adults presenting with testicular masses.

The occurrence of a metastatic mixed germ cell tumour in a patient with untreated cryptorchidism, hypospadias, and underlying persistent Müllerian duct syndrome is rare.It is important to consider disorders of sex development when evaluating adult males with testicular malignancy and a history of genitourinary anomalies.A collaborative approach involving urology, oncology, radiology, and genetics is essential for accurate diagnosis and optimal management.