Residual mediastinal masses are frequently observed in @entity1 with @entity978 ( @entity978 ) after completed therapy, and the discrimination between active @entity5 tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by @entity419 (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight @entity978 @entity1 with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 "subjects." @entity1 were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). @entity5 was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive @entity1 at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an @entity978 @entity1 with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.

Thoracic positron emission tomography using XXXX for the evaluation of residual mediastinal @entity978 .

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients', 'patient'] @entity978 :: ('MESH:D006689', 'Disease') :: ['HD', 'Hodgkin disease'] @entity419 :: ('MESH:D019788', 'Chemical') :: ['18F-fluorodeoxyglucose'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'A PET-negative mediastinal tumor']
@entity419 :: (MESH:D019788,Chemical) :: ['18F-fluorodeoxyglucose']
