Background: A residual mediastinal mass is common after treatment for bulky mediastinal lymphoma and represents a difficult diagnostic problem.
Patients and methods: 19 patients with bulky mediastinal masses due to malignant lymphoma had computed tomography (CT), magnetic resonance imaging (MRI) and 67Gallium scan (67Ga) before treatment, after four cycles of chemotherapy, and two, six and twelve months after end of treatment.
Results: MRI and 67Ga showed active tumor in all patients before treatment. Twelve months after treatment full consistency was found between the results of the two techniques. During treatment and the first six months after treatment, the two techniques were not in accord in some patients, partly due to later normalization of MRI compared with 67Ga.
Conclusion: Both MRI and 67Ga are useful in assessing tumor activity in lymphoma mediastinal masses.