The primary symptom of cancer in the spleen is a significant enlargement in size, according to WebMD. The spleen is usually the size of a fist, but cancer is one disease that potentially makes it swell many times the normal size.
Just because the spleen expands in size does not automatically mean that the patient has spleen cancer. In some cases, the spleen has simply been overactive and has expanded in size. One example would involve excess activity in eradicating blood cells, a condition known as hypersplenism, notes WebMD.
Viral, parasitic and bacterial infections such as mononucleosis and endocarditis are also common causes of enlargement in the spleen. Cirrhosis, other liver conditions, blood diseases, issues with the lymph system and inflammatory diseases also can cause a change in size. Both leukemia, a cancer involving the displacement of normal blood cells with white blood cells, and lymphoma, a cancer of the lymph tissue, sometimes cause the spleen to enlarge. If cancer has metastasized to the spleen from elsewhere in the body, the spleen sometimes grows in size. Cysts, abscesses and injury sometimes cause this change. The possible causes make spleen enlargement a cause for concern and a reason to visit the doctor, states WebMD.