Primary Malignancy in a Supernumerary Testicle Presenting as a Large Pelvic Mass.

Area of Science:

• Urology
• Oncology

Background:

• Polyorchidism (supernumerary testis) is a rare congenital anomaly.
• Seminoma is the most common type of testicular germ cell tumor.

Observation:

• A 35-year-old male presented with abdominal pain and an abdominal mass.
• Physical examination revealed a palpable, undescended left testicle in the inguinal canal, diagnosed as seminoma.

Findings:

• The undescended testicle was surgically removed, and the patient received chemotherapy.
• This case represents an unusual presentation of polyorchidism with the supernumerary testis affected by seminoma.

Implications:

• Consider malignancy in an extranumerary testicle when testicular cancer is suspected but not found in palpable testes.
• This case underscores the importance of thorough evaluation in suspected testicular cancer, including rare anomalies like polyorchidism.