Testicular cancer

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A 35-year-old man presents for evaluation of a painless right testicular mass. The patient first noticed the mass 3 weeks ago while showering, and he is not sure if it has been enlarging. Medical history is notable for right-sided cryptorchidism as a child, which was treated via orchiopexy at the age of 1. Temperature is 37.1°C (98.8°F), pulse is 67/min, and blood pressure is 105/77 mmHg. Physical examination reveals a nontender nodule on the right testicle which does not transilluminate or decrease in size when the patient lies flat. After further diagnostic testing is performed, the physician suspects a testicular cancer and schedules an orchiectomy. Gross analysis of the tumor reveals a homogenous mass with no hemorrhage or necrosis. Histological examination reveals the following:



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Which of the serum markers was most likely elevated prior to orchiectomy?

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Testicular cancers are malignant tumors that form in one or both testes. They usually present as a mass that’s often detected in the early stages since they are on an organ that’s easily accessible during physical examination. Thus, they typically have a good prognosis.

The testes are a pair of male reproductive glands the size of small plums, that are located in the scrotum. The testes themselves are covered on the outside by the tunica albuginea, a white, fibrous layer.

If we slice a testis open and look inside, sorry for the cringe moment, we can see septa that partition each testis into lobules. Each lobule contains up to four seminiferous tubules, where sperm is synthesized.

Now let’s zoom in on a single seminiferous tubule, which is the “sperm factory”. A seminiferous tubule has a thick wall of epithelial cells that surround a fluid-filled lumen, a bit like a garden hose.

The wall of the tubule is made up of two kinds of cells: at the periphery, there’s the germ cells known as spermatogonia, which are the primordial sperm cells that begin dividing over and over in puberty, and give rise to male gametes.

Next to them are Sertoli cells which are large cells that extend from the margin all the way to the lumen of the tubule. Sertoli cells are supportive cells that provide nutrients to developing sperm cells, and contribute to the blood-testis barrier by only allowing certain molecules, like testosterone, into the seminiferous tubules.

Outside the tubule, there’s connective tissue with capillaries, as well as Leydig cells - another supportive cell which produces testosterone, which is a hormone necessary for the proper development of sperm.

During fetal development the entire body derives from three layers called germ layers; the ectoderm, mesoderm and endoderm.

Summary

Testicular cancers are malignant tumors that form in one or both testes. They usually present as a mass that's often detected in the early stages. Major types of testicular cancer include germ-cell testicular cancer and non-germ-cell testicular cancer. Germ cell testicular cancers come from germ cells that normally develop into sperm.

Their five main subtypes include seminomas, teratomas, yolk sac tumors or endodermal sinus tumors, choriocarcinoma or placental tissue tumors, and embryonal carcinomas. Non-germ cell testicular cancers come from the Sertoli cells or the Leydig cells which can secrete excess sex hormones. Risk factors for developing testicular cancer include cryptorchidism, Klinefelter syndrome, and in-utero exposure to pesticides and synthetic sex hormones. Treatment of testicular cancer involves surgery, chemotherapy, and radiotherapy.

Sources

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