Routes of lymphatic spread of testicular cancer
The lymphatic drainage of the testicles follows the gonadal venous drainage, with the left side draining to the pre-aortic or left para-aortic retroperitoneal lymph nodes near the renal hilum and the right side draining to the aortocaval or pericaval retroperitoneal lymph nodes. As such, testicular cancer tends to first spread via the lymphatics to these regional lymph nodes, skipping the pelvic lymph nodes.
Epididymal lymphatic drainage not only follows the gonadal venous drainage to the retroperitoneum, but also goes to the external iliac nodes. Lymphatic drainage from the scrotal skin is typically to the inguinal nodes. Therefore, pelvic lymphadenopathy may occur when there is tumor invasion of the epididymis or scrotal wall or when there has been prior scrotal or inguinal surgery.