"Hot" spleen on Tc-99m sulfur colloid images

In routine Tc-99m sulfur colloid (SC) liver-spleen imaging, relatively increased splenic uptake when compared with liver uptake is frequently seen. Commonly this is due to decreased hepatic uptake secondary to liver disease, but often it is because of increased uptake in the hyperfunctioning spleen. Reported is a case of lymphoma of the tonsil, with a "hot" spleen which was free of tumor. Possible etiology of the "hot" spleen is discussed and the known causes listed according to their prevalence.