The negative predictive value (PV-) and positive predictive value (PV+) of gallium-67 scintigraphy and computed tomography (CT) were compared after treatment in 43 patients with Hodgkin disease and in 56 patients with non-Hodgkin lymphoma. The usefulness of these studies in predicting survival was also evaluated. In patients with Hodgkin disease, the PV- of Ga-67 scintigraphy was 0.84 and of CT was 0.88. The PV+ was 0.80 for Ga-67 studies and only 0.29 for CT. In patients with non-Hodgkin lymphoma, the PV- of Ga-67 scintigraphy was 0.84 and of CT was 0.80. The PV+ was 0.73 and 0.35, respectively. For both groups, the differences in disease-free survival between patients with negative and positive Ga-67 studies were significant (P less than .05 in Hodgkin disease and P less than .001 in non-Hodgkin lymphoma), but the differences were not significant for CT. These data show that, after treatment of patients with lymphoma, Ga-67 scintigraphy is a good predictor of clinical outcome and can be used beneficially in patient treatment.