[Effectiveness of (67)Ga scintigraphy in the diagnosis of lymphoma relapse]. / Efectividad de la gammagrafía con 67Ga en el diagnóstico de recidiva de linfomas.

PURPOSE: To establish the clinical effectiveness of 67Ga in lymphoma recurrence. PATIENTS AND METHODS: Thirty-nine patients were assessed on 43 occasions (31 for Hodgkin's disease and 12 for non-Hodgkin's lymphoma) either for a suspected recurrence or to monitor the evolution of the disease. A computed tomography (CT) and a 67Ga whole body scan were performed. Independent observers who did not know the definitive diagnosis performed the CT and 67Ga readings. The gold standard was the biopsy results or the follow-up during a 12 months period. RESULTS: Recurrence was confirmed in 17 cases, while 26 continued to have complete remission. Using 67Ga resulted in true positive (TP), 24 true negative (TN), 2 false positive (FP) and 2 false negative (FN) results with a sensitivity of 0.88 (15/17), specificity of 0.92 (24/26), positive predictive value (PPV) of 0.88 (15/17) and negative predictive value (NPV) of 0.92 (24/26), while CT produced 12 TP, 20 TN, 6 FP and 5 FN, with a sensitivity of 0.7 (12/17), specificity of 0.77 (20/26), PPV of 0.88 (12/18) and NPV of 0.92 (20/25). CONCLUSIONS: 67Ga is a useful indicator and has better diagnostic effectiveness than CT for both the confirmation and exclusion of lymphoma recurrence.