EBV and KSHV are associated with a variety of malignancies including some lymphomas, carcinomas and other malignancies. We anticipate that viral TK expression will differ among tumor types and will be adjusted with standard chemotherapies and some investigational agents. This exploratory study is aimed in part at evaluating whether standard regimens or investigational regimens might bring about sufficient activation of the EBV-TK or KSHV-TK in tumors to be therapeutically useful if used in conjunction with FIAU as a radiopharmaceutical.