This study will investigate the safety and efficacy of the combination of GCS-100 with etoposide and dexamethasone. In vitro data demonstrates potentiation of the killing of lymphoma cells when GCS-100 is combined with dexamethasone or etoposide (Linda Baum, unpublished data; Finbarr Cotter et al, Annals of Oncology, vol 16, 205, Suppl 5.) GCS-100 will be administered in increasing doses to define a maximum tolerated dose (MTD) in combination with these chemotherapeutic agents. When the MTD is defined, the cohort will be expanded to characterize the efficacy of this combination.