Metastasis
Seminomas do not metastasize until they are of a considerable size, and then they invade the para-aortic lymph nodes and the iliac lymph nodes. Hematogenous spread of seminomas is rare. On the other hand, non-seminomas can spread by hematogenous as well as by lymphatic routes. Signs of metastasis include respiratory symptoms, gastrointestinal symptoms, anemia, neck masses, headaches, jaundice with liver metastasis, pedal edema due to an inferior vena cava obstruction, and back pain.
Liver involvement and lung involvement is due to the hematogenous spread of the tumor (spread through the blood). Liver involvement can lead to multiple problems because the liver is the main metabolization organ of the body, causing symptoms such as jaundice, clotting factors deficiency (bleeding disorders), oncotic protein deficiency, such as globulin and albumin (loss of oncotic pressure of blood leads to edema).
Kidney involvement can also lead to multiple problems such as anemia (erythropoietin deficiency), hypertension (due to derangement of electrolyte metabolism, and loss of Renin angiotensin aldosterone system), hydronephrosis (pressure on ureters). Finally, lung metastasis and mediastinal lymphadenopathy can cause respiratory symptoms explained earlier.