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Testicle Cancer

Testicle cancer is the most common solid tumor in men between the ages of 20 and 35 years. There are three modal peaks: infancy, ages 25 to 40, and about age 60. A solid testicular mass in a man aged 50 or greater is usually a lymphoma. An estimated 6000 new cases and 350 deaths due to testicle cancer occured in the United States in 1995. The lifetime probability of developing a GCT is approximately 0.2% for an American Caucasian male. The incidence of testis cancer varies significantly according to geographic area. The reported incidence is highest in Scandinavia, Switzerland, Germany, and New Zealand; intermediate in the United States and Great Britain; and lowest in Africa and Asia. The worldwide incidence of testis GCT has more than doubled in the past 40 years testicular cancer.

EPIDEMIOLOGY

GCTs are seen principally in young Caucasians, rarely in African-Americans. The published ratio between Caucasian and African-American patients is approximately 4 to 5:1, although it was closer to 40:1 ratio in the US Military. In African-Americans, GCT behaves similarly.

The cause of GCT is unknown. Hypotheses implicating an endocrine-driven, pituitary stimulation.

CRYPTORCHIDISM

The risk of GCT occurring in the cryptorchid testis is several times the risk in normally descended testes. Between 5% and 20% of patients with a history of cryptorchidism develop a tumor.

INITIAL PRESENTATION AND MANAGEMENT

SYMPTOMS AND SIGNS

The pathognomonic presentation of a primary testicular tumor is a painless testicular mass that may range in size from a few millimeters to several centimeters. However, the painless testicular mass occurs in only a minority of patients. The majority present with more diffuse testicular pain, swelling, hardness, or some combination of these findings. Because infectious epididymitis or orchitis.

DIAGNOSIS

A radical inguinal orchiectomy, using an inguinal incision with early high ligation of the spermatic cord at the deep inguinal ring, minimizes local tumor recurrence and aberrant lymphatic spread and is the only acceptable therapeutic and diagnostic procedure. The vasal and vascular components are doubly clamped and divided separately; their respective stumps are pushed into the retroperitoneal space to facilitate future removal of the gonadal vessels at the time of retroperitoneal lymph node dissection (RPLND). The testicle and spermatic cord are removed en bloc, avoiding any spillage, and meticulous hemostasis is achieved. The testis embryologically originates in the genital ridge, and descends during fetal life through the abdomen and inguinal canal into the scrotum. Therefore, the primary lymphatic and vascular drainage of the testis is to the retroperitoneal lymph nodes and the renal or great vessels.

Extragonadal GCTs comprise fewer than 10% of all GCT presentations. The mediastinum and retroperitoneum are the most common primary sites. Pineal tumors, occurring most frequently in children, are usually GCT. Because of their unique access to the meninges, the metastatic pattern of pineal germ GCT includes intradural sites along the neuraxis and is infrequently systemic.

HISTOLOGY

CARCINOMA IN SITU

Carcinoma in situ (CIS) (intratubular germ cell neoplasia) precedes invasive testicular GCT in virtually all cases of typical and anaplastic seminoma and all nonseminomatous histologies in the adult.

SEMINOMA

Seminoma accounts for approximately 50% of all GCT and most frequently appears in the fourth.

NONSEMINOMATOUS GERM CELL TUMORS

Nonseminomatous histology comprises about 50% of all GCTs.

Embryonal Carcinoma

Embryonal carcinoma is the most undifferentiated somatic cell type. Individual cells are epithelioid.

Choriocarcinoma

By definition, choriocarcinoma consists of both cytotrophoblasts and syncytiotrophoblasts. If cytotrophoblasts are not present, then the diagnosis of choriocarcinoma cannot be made. Pure choriocarcinoma is an extremely rare presentation usually associated with widespread hematogenous prognostic value by themselves.

Yolk Sac Tumor

Yolk sac tumor (endodermal sinus tumor) is often confused with a glandular form of embryonal carcinoma. This tumor mimics the yolk sac of the embryo and produces alpha-fetoprotein (AFP).

Teratoma

A teratoma is composed of somatic cell types derived from two or more germ layers (ectoderm, mesoderm, or endoderm). Mature teratoma consists of adult-type differentiated elements such as cartilage, glandular epithelium, nerve tissue, or other differentiated cell types. Immature teratoma generally refers to a tumor with partial somatic differentiation, similar to that seen in a fetus.

MANAGEMENT OF CLINICAL STAGE I DISEASE

SEMINOMA

Radiation Therapy

The management of clinical stage I seminoma has not changed significantly in the last 20 years. Radiation therapy remains the treatment of choice. The ipsilateral hemiscrotum does not require therapy.

NONSEMINOMATOUS GERM CELL TUMORS

Nonseminomatous GCT is relatively radioresistant. Therefore, radiation therapy plays no role in its initial management. If a patient has clinical stage I disease at the conclusion of initial staging.

Retroperitoneal Lymph Node Dissection

Because of predictable lymphatic metastatic spread, the conventional approach to patients with clinical stage I nonseminomatous GCT has been the modified, bilateral RPLND.

Despite refinement of radiologic imaging, 15% to 40% of patients are clinically understaged. Retroperitoneal metastases will be found in about 30% of patients judged preoperatively to be clinical stage I. Retroperitoneal relapse will occur in about 20% to 25% of patients on clinical stage I.

Chemotherapy

There are few data regarding chemotherapy as initial treatment of clinical stage I disease when the risk of retroperitoneal disease is high. In three reports of patients receiving two cycles of cisplatin-based chemotherapy, fewer than 5% relapsed and about 1% died of GCT.

MANAGEMENT OF CLINICAL STAGE II (LOW TUMOR BURDEN)

SEMINOMA

Low tumor burden stage II seminoma includes all patients with retroperitoneal metastases measuring 5 cm or smaller in maximum transverse diameter. This encompasses both clinical stages IIA and IIB.

NONSEMINOMATOUS GERM CELL TUMORS

Low tumor burden clinical stage II nonseminomatous GCT encompasses disease ipsilateral to the primary tumor, at or below the renal hilum, not associated with tumor-related back pain, and limited.

Retroperitoneal Lymph Node Dissection

The standard approach to patients with clinical stage IIA and some IIB tumors has been RPLND.

Adjuvant Chemotherapy

Early studies showed a lower risk of relapse when fewer than six nodes were involved and no node was 2 cm; and higher when 6 nodes or more were involved, any node was larger than 2 cm, or extranodal extension was present.

Surveillance is a treatment choice for compliant patients with fewer than six involved nodes.