Testicular cancers are the most common malignancy in men between the ages of 20 and 34 years.

Epidemiology

Testicular cancer is uncommon, accounting for less than 1% of all internal organ malignancies ².

The commonest histology of the tumor varies with the age of affected individuals. Over 90% of all tumors of the testes are primary germ cell tumors, and as such young adults are the overall most frequently involved group:

• 1^st decade: yolk sac tumor and testicular teratoma

• 2^nd decade: choriocarcinoma

• 3^rd decade: embryonal cell carcinoma

• 4^th decade: seminoma

• ≥7^th decade: lymphoma (usually non-Hodgkin lymphoma) and spermatocytic seminoma

Risk factors

• cryptorchidism

• family history

• radiation

• previous history of contralateral testicular tumor

• infections: HIV, mumps, etc.

• microlithiasis

• hypospadia

See: risk factors for testicular germ cell tumors

Clinical presentation

In a large case-control study, the commonest symptoms associated with a diagnosis of testicular cancer were a swollen testis/scrotum and/or a lump ⁴. 

Pathology

Classification

• primary tumor: 94% of all tumors

  • testicular germ cell tumor: 90% of primary tumors

    • testicular seminoma: 40% of germ cell tumors ¹

      • classic

      • anaplastic

      • spermatocytic

    • non-seminomatous germ cell tumor (NSGCT): 60% of germ cell tumors

      • testicular mixed germ cell tumor: (~33%, typically one or more NSGCTs and seminoma) ²

      • testicular embryonal cell carcinoma (~10%)

      • testicular teratoma (~4%)

      • testicular yolk sac tumor (~1%)

      • testicular choriocarcinoma (~0.3%)

  • testicular non-germ cell tumor: 10% of primary tumors

    • Sertoli cell tumor

    • Leydig cell tumor

    • granulosa cell tumor of the testis

    • fibroma-thecoma of the testis

  • primary testicular lymphoma

• secondary tumor: 6% of all tumors

  • secondary testicular lymphoma

  • testicular leukemia

  • metastasis to testis

Regional lymph nodes

The following retroperitoneal lymph node stations are considered regional:

• aortocaval

• para-aortic

• paracaval

• preaortic

• precaval

• retroaortic

• retrocaval

The left and right testes have differing lymphatic drainage. The left testis primarily drains through the para-aortic lymph nodes. The right testis primarily drains through the aortocaval nodes.

Metastatic sites

Metastases from testicular tumors most commonly occur to the lymphatic system followed by lung, liver and bone, and other visceral sites.

Staging

• testicular cancer staging

Radiographic features

See the individual articles.

See also

• unilateral testicular lesions

• bilateral testicular lesions

• paratesticular lesions