GA-67 SCINTIGRAPHY FOR THE EVALUATION OF RECURRENCES AND RESIDUAL MASSES IN PATIENTS WITH LYMPHOMA

Ga-67 scintigraphy has proven to be of value in the evaluation of pati ents with lymphoma, especially in their management after treatment. In this study, computed tomography (CT) and Ga-67 scans were compared in 53 patients with lymphoma who had previously been treated. Twenty-eig ht were patients in continuous clinical remission in whom recurrence w as suspected. The remaining 25 patients were studied between 1 and 3 m onths post-treatment to assess a residual mass. The sensitivity for th e detection of lymphoma recurrence was 88% for Ga-67, with two false-n egative results, and 59% for CT, with seven false-negative results. In the diagnosis of recurrence, the specificity of Ga-67 was 100% and th at of CT 72%, with three false-positive results. Therapeutic response was assessed in 25 patients and the ability to predict response to tre atment resulted in a specificity of 86% for Ga-67 and 81% for CT. Trea tment failed in four patients, as detected by Ga-67 scan, whereas CT d id not detect any of these. In the remaining 21 patients who showed go od response to treatment, there were three false-positive results for Ga-67 and four for CT. Ga-67 scintigraphy can detect relapse more accu rately and much earlier than CT, as well as diagnose complete remissio n after treatment. Therefore, Ga-67 scintigraphy should be used routin ely in monitoring response to treatment in lymphoma.