Chapter 092. Testicular Cancer (Part 2) The regional draining lymph nodes for the testis are in the retroperitoneum, and the vascular supply originates from the great vessels (for the right testis) or the renal vessels (for the left testis). As a result, the lymph nodes that are involved first by a right testicular tumor are the interaortocaval lymph nodes just below the renal vessels. For a left testicular tumor, the first involved lymph nodes are lateral to the aorta (para-aortic) and below the left renal vessels. In both cases, further nodal spread is inferior, contralateral, and, less commonly, above the renal hilum. Lymphatic involvement can extend cephalad to the retrocrural, posterior mediastinal, and supraclavicular lymph nodes. Treatment is determined by tumor histology (seminoma versus nonseminoma) and clinical stage (Table 92-1). Table 92-1 Germ Cell Tumor Staging and Treatment Treatment Stage Extent of Disease Seminoma Nonseminoma IA Testis only, no vascular/lymphatic invasion (T1) Radiation therapy RPLND or observation IB Testis only, with vascular/lymphatic invasion (T2), or extension through tunica albuginea (T2), or involvement of spermatic cord (T3) or scrotum (T4) Radiation therapy RPLND IIA Nodes < 2 cm Radiation RPLND or chemotherapy often therapy followed by RPLND IIB Nodes 2–5 cm Radiation therapy RPLND +/– adjuvant chemotherapy or chemotherapy followed by RPLND IIC Nodes > 5 cm Chemotherapy Chemotherapy, often followed by RPLND III Distant metastases Chemotherapy Chemotherapy, often followed by surgery (biopsy or resection) Note: RPLND, retroperitoneal lymph node dissection. Pathology GCTs are divided into nonseminoma and seminoma subtypes. Nonseminomatous GCTs are most frequent in the third decade of life and can display the full spectrum of embryonic and adult cellular differentiation. This entity comprises four histologies: embryonal carcinoma, teratoma, choriocarcinoma, and endodermal sinus (yolk sac) tumor. Choriocarcinoma, consisting of both cytotrophoblasts and syncytiophoblasts, represents malignant trophoblastic differentiation and is invariably associated with secretion of hCG. Endodermal sinus tumor is the malignant counterpart of the fetal yolk sac and is associated with secretion of AFP. Pure embryonal carcinoma may secrete AFP or hCG, or both; this pattern is biochemical evidence of differentiation. Teratoma is composed of somatic cell types derived from two or more germ layers (ectoderm, mesoderm, or endoderm). Each of these histologies may be present alone or in combination with others. Nonseminomatous GCTs tend to metastasize early to sites such as the retroperitoneal lymph nodes and lung parenchyma. One-third of patients present with disease limited to the testis (stage I), one-third with retroperitoneal metastases (stage II), and one-third with more extensive supradiaphragmatic nodal or visceral metastases (stage III). Seminoma represents about 50% of all GCTs, has a median age in the fourth decade, and generally follows a more indolent clinical course. Most patients (70%) present with stage I disease, about 20% with stage II disease, and 10% with stage III disease; lung or other visceral metastases are rare. Radiation therapy is the treatment of choice in patients with stage I disease and stage II disease where the nodes are <5 cm in maximum diameter. When a tumor contains both seminoma and nonseminoma components, patient management is directed by the more aggressive nonseminoma component. . Chapter 092. Testicular Cancer (Part 2) The regional draining lymph nodes for the testis are in the retroperitoneum,. lymph nodes that are involved first by a right testicular tumor are the interaortocaval lymph nodes just below the renal vessels. For a left testicular tumor, the first involved lymph nodes. or observation IB Testis only, with vascular/lymphatic invasion (T2), or extension through tunica albuginea (T2), or involvement of spermatic cord (T3) or scrotum (T4) Radiation therapy