[Torsion of a testicular cancer in cryptorchidism prolapsing out of the inguinal canal: a case report].

A 47-year-old man visited our hospital suffering from intensive pain of the swelling mass in his left inguinal region. He had never recognized the left testis in his scrotum, and felt the left inguinal mass growing slowly since a year ago. Computed tomography and Doppler uitrasonography revealed a mass approximately 5 cm in diameter separating from intestines in the abdominal cavity and not supplied sufficient blood flow. We suspected that the mass was a testicular cancer in cryptorchidism with testicular torsion and performed orchiectomy. At the time of the operation, the mass and the spermatic cord were twisted and prolapsed out of the aponeurosis of external abdominal oblique muscle. Histopathologically, malignant degeneration was demonstrated in the undescended testis, and the cell type was seminoma. We definitely diagnosed the mass as torsion of a testicular cancer in cryptorchidism prolapsing out of the inguinal canal.