Purpose: To evaluate the utility of periodic gallium (67Ga) scans in the management of patients with Hodgkin's disease.
Patients and methods: From 1990 to 1994, 101 patients treated for Hodgkin's disease (stage I to II, n = 67; stage III to IV, n = 34) had a positive 67Ga scan at the time of diagnosis. Treatment included chemotherapy in 27 patients, radiation therapy in 28, and combined modality therapy in 46. All patients underwent 67Ga scans at the time of diagnosis, near the end or just after treatment, and at periodic follow-up evaluation.
Results: After treatment, the 67Ga scan remained positive in four patients and was interpreted as negative in 97. Among the four patients with positive scans, two died of progressive disease and two relapsed. Among the remaining 97 patients with negative 67Ga scans, 16 patients relapsed, including five with stage I to II (7.5%) and 11 with stage III to IV (34.4%) disease. The negative predictive value of posttherapy 67Ga scan was 83.5% for all patients; however, when calculated according to stage, it was 92.4% for patients with stage I to II disease and 64.5% for patients with stage III to IV disease (P < .01).
Conclusion: A positive 67Ga scan at the end of therapy is rarely seen in patients with Hodgkin's disease and should be considered a manifestation of gross residual disease. However, a negative 67Ga scan after therapy had a significantly lower predictive value in patients with stage III to IV disease compared with stage I to II disease. The predictive value of 67Ga scans, as well as newer imaging studies, should be analyzed according to pretreatment stage.