Fig. 1: Axial CT image of the abdomen at the level below the left renal vein shows large matted left paraaortic lymph nodes (arrowheads) in a 32-year-old man.
Fig.2: Testicular ultrasound was performed to search for a primary tumor. Sagittal ultrasound image of the left testis shows a small hypoechoic mass in the testis.
- Can be divided into subgroups based on relationship with aorta and IVC: right lateroaortic (aortocaval, laterocaval, precaval, retrocaval), left lateral aortic, preaortic, retroaortic.
- Paraaortic pathway spread of tumor bypasses lymph nodes in pelvis, most common in ovarian and testicular carcinoma
- From ovaries and testicles, lymphatic vessels follow gonadal vessels to paraaortic or paracaval lymph nodes at the renal hila.
- Search for testicular/ovarian tumors if you see isolated paraaortic lymphadenopathy below the renal hila!
- Two sets of lymph drainage, superficial and deep
- Superficial vessels drain surface of tunica vaginalis
- Deep vessels drain epididymis and testis
- Right testicular tumor can spread across midline, whereas left testicular tumors usually do not
- Occasionally, external iliac nodes drain the testis