A 34-year-old man comes to the physician because of a left testicular swelling. He has no pain. He appears healthy. His vital signs are within normal limits. Examination shows an enlarged, nontender left testicle. A scrotal ultrasound reveals a suspicious, partially necrotic mass. Serum lactate dehydrogenase and alpha-fetoprotein levels are markedly elevated. The patient undergoes a left radical inguinal orchiectomy. Which of the following is the most likely histologic diagnosis?

Question

A 34-year-old man comes to the physician because of a left testicular swelling. He has no pain. He appears healthy. His vital signs are within normal limits. Examination shows an enlarged, nontender left testicle. A scrotal ultrasound reveals a suspicious, partially necrotic mass.  Serum lactate dehydrogenase and alpha-fetoprotein levels are markedly elevated.  The patient undergoes a left radical inguinal orchiectomy.  Which of the following is the most likely histologic diagnosis?

Quizplus · Accepted Answer

Eductional Objective: Most cases of testicular cancer are either seminomatous or nonseminomatous germ cell tumors.  Nonseminomatous germ cell tumors are composed of partially differentiated germ cells, which often retain the ability to secrete human chorionic growth hormone and alpha-fetoprotein (serum tumor markers).  Serum lactate dehydrogenase, a marker of tissue injury and cell turnover, is also frequently increased.

A 34-Year-Old Man Comes to the Physician Because of a Left