Gallium-67 scans as an adjunct to computed tomography scans for the assessment of a residual mediastinal mass in pediatric patients with hodgkin's disease. A pediatric oncology group study

Abstract

This study determines the utility of gallium-67 (Ga-67) scintigraphs as an adjunct to computed tomography (CT) scans for the assessment of residual mediastinal masses in children and adolescents with advanced-stage Hodgkin's disease. At diagnosis 42 patients with CT scan-documented mediastinal disease had a Ga-67 scan performed. Thirty-four of 42 patients (81%) had gallium-avid mediastinal lesions, whereas in eight (19%), the Ga-67 scan was negative. At the completion of eight cycles of therapy of Mustargen (mechlorethamine), Oncovin (vincristine), procarbazine, prednisone (MOPP) alternating with doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD), 21 of 34 patients with initially positive Ga-67 scans had them repeated; 18 of 21 converted to negative results, and three remained positive. In 11 of 18 patients, the loss of gallium avidity was consistent with a negative mediastinal CT scan. In seven, although the gallium scan was negative, the CT scan remained positive; all seven patients had a mediastinal biopsy of suspected residual disease and in all seven the biopsy results were negative for Hodgkin's disease. These preliminary results in a small cohort of patients demonstrate that Ga-67 scans may be of benefit in evaluating residual mediastinal masses in patients with Hodgkin's disease.