Testicular Abnormality in a Young Man

A 21-year-old man presents with a "swelling" in the testicle that he first noticed about 1 month earlier while showering. He does not recall any previous scrotal tenderness; because he has been frequently palpating the lesion, he cannot say for certain whether it is currently tender. He is sexually active but denies any symptoms of sexually transmitted disease: specifically, urethral discharge, penile lesions, or vesicles. He is otherwise healthy and takes no long-term medications.

PHYSICAL EXAMINATION AND LABORATORY RESULTS

The patient is anxious but appears well. Lymph nodes at all sites are normal. There is no gynecomastia. His chest is clear and his heart is normal. No enlarged masses or organs are noted in the abdomen. Examination of the testicles reveals a nontender 5- to 6-cm hard mass in the left testicle. The remainder of the genitalia, including the epididymis, is normal.

A hemogram and results of a chemistry profile and urinalysis are all normal.

Which of the following statements concerning this patient is most accurate?

A.

He requires an immediate trans-scrotal testicular biopsy.

B.

The most likely pathological diagnosis here is choriocarcinoma.

C.

Serum tumor marker levels should be measured because they figure in the staging of his disease.

D.

The prognosis is uniformly poor.

(Answer on next page.)

CORRECT ANSWER: C

An essentially painless scrotal mass in a young man is almost certainly a testicular germ cell tumor. Germ cell tumors account for 95% of testicular tumors; lymphomas account for most of the rest. In men between the ages of 17 and 35 years, germ cell tumors are the most common solid tumor. The incidence is significantly higher in white men than in African American men. Although a cryptorchid testis is a well-known risk factor for testicular cancer, only a small minority of affected patients have a history of cryptorchidism.¹ Thus, it is reasonable to assume that this young man has testicular cancer.

Diagnosis of a suspected testicular germ cell tumor. Although tissue biopsy is required to make the diagnosis, initially ultrasonography is used to confirm that the mass is intratesticular and to determine whether it is solid or has a mixed solid and cystic structure. This study excludes nontesticular lesions such as hernia, varicocele, and scrotal hematoma from trauma. Demonstration of a normal epididymis excludes epididymitis.

Once an ultrasound scan has confirmed a solid (or mixed) intratesticular mass, the procedure of choice is a radical orchiectomy with ligation of the spermatic cord at the inguinal ring. Trans-scrotal biopsy (choice A) and orchiectomy are contraindicated because both leave intact the inguinal portion of the cord (the embryological origin of the testis), thus predisposing the patient to metastases of the scrotal skin or inguinal or pelvic lymph node.²

Identification of tumor type and disease staging. Coincident with obtaining tissue, order tests for serum tumor markers and CT imaging of the abdomen, pelvis, and chest. CT determines whether lymph node metastasis is present anywhere from the retroperitoneal area to the chest. Lymph node metastasis is common in germ cell tumors, and its presence and extent affect the determination of clinical stage, prognosis, and therapy.

Serum tumor marker levels are extremely important in germ cell tumors. They are used in conjunction with biopsy results to determine tumor type. Elevated a-fetoprotein (AFP) levels indicate the presence of a nonseminomatous tumor (embryonal and/or yolk sac). Elevated b-human chorionic gonadotropin (b-HCG) levels may be associated with seminoma and yolk sac tumors.

The levels of these tumor markers are also key factors in the staging of early germ cell tumors (choice C). Normal levels without lymph node involvement indicate stage IA or stage IB disease (depending on tumor size), while elevated levels of AFP (but less than 1000 ng/mL) and b-HCG (but less than 5000 mIU) along with lymph node involvement define stages IIA and IIB. Tumor marker levels that are extremely high (more than 1000 ng/mL for AFP, and more than 5000 mIU for b-HCG) usually indicate metastatic disease.^2,3

Epidemiology of tumor types. Incidences of the various types of germ cell tumors are seminomas, 50%; mixed nonseminomatous germ cell tumors, 35%; and pure nonseminomatous germ cell tumors, 15% (with embryonal, 10%; teratoma, 3% to 5%; and the uncommon pure yolk sac tumor and choriocarcinoma, 1% each).³ In a young man, seminoma is the most likely tumor type; choriocarcinoma (choice B) is the least likely.

Prognosis. The treatment of germ cell tumors is one of the triumphs of oncology; results are excellent in most patients. Effective therapy has significantly improved the prognosis for patients with this once frequently lethal condition. Thus, choice D is incorrect. Patients with stage I or stage II disease (about 75% of all patients) have a 5-year survival rate of 92% overall, 89% disease-free. Those with highly elevated tumor marker levels have a 5-year survivorship of 80% overall, 75% disease-free. Even patients with ultrahigh tumor marker levels and visceral metastases have a 5-year overall survivorship of 48%; disease-free, 41%.

Management depends on stage and histological findings; therapies include surgery (radical retroperitoneal lymph node dissection) and combination chemotherapy.

Outcome of this case. Testicular ultrasonography confirmed a 5-cm intratesticular solid mass. A radical orchiectomy revealed a pure embryonal cell carcinoma. A CT scan was negative for lung nodules and lymphade-nopathy. The AFP level was 11 ng/mL; the b-HCG level and the lactose dehydrogenase level were normal. Two weeks after surgery, all tumor marker levels were normal. The patient is currently being followed up with chest films and strict active surveillance of tumor marker levels.

References:

REFERENCES:

1.

Devesa SS, Blot WJ, Stone BJ, et al. Recent cancer trends in the United States.

J Natl Cancer Inst.

1995;87:175-182.

2.

Bosl GJ, Motzer RJ. Testicular germ-cell cancer.

N Engl J Med.

1997;337:242-253.

3.

Kaufman DS, Saksena MA, Young RH, Tabatabaei S. Case records of the Massachusetts General Hospital. Case 6-2007. A 28-year-old-man with a mass in the testis.

N Engl J Med.

2007;356:842-849.