title: Thallium-201 scintigraphy for assessment of a gallium-67-avid mediastinal mass following therapy for Hodgkin's disease.
abstract: Differentiating thymic rebound from recurrent tumor may be difficult in pediatric patients following chemotherapy for Hodgkin's disease. We present a patient who had both a negative 67Ga scan and computed tomography (CT) of the chest at diagnosis and demonstrated gallium avidity and CT evidence of a new mediastinal mass at the completion of chemotherapy. There was, however, no other clinical or laboratory evidence of disease recurrence. Thallium-201 imaging was subsequently performed and demonstrated no significant radionuclide accumulation within this anterior mediastinal mass. CT shows only the presence of a mass, but not it's nature. Gallium-67 scintigraphy, while used widely as an indicator of tumor viability, may demonstrate increased uptake in cases of thymic rebound. Thallium-201 imaging has previously been shown to demonstrate increased uptake in mediastinal malignancy. Conversely, no significant mediastinal uptake of 201Tl, as in this case, provides additional supportive evidence for a benign mediastinal entity such as thymic rebound.
authors.affiliation: Department of Radiology, Hackensack Medical Center, New Jersey 07601.
authors.forename: E W
authors.initials: EW
authors.lastname: Harris
authors.forename: J I
authors.initials: JI
authors.lastname: Rakow
authors.forename: M
authors.initials: M
authors.lastname: Weiner
authors.forename: H
authors.initials: H
authors.lastname: Agress
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005710:Gallium Radioisotopes; D006689:Hodgkin Disease / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008479:Mediastinal Neoplasms / Q000000981:diagnostic imaging / Q000209:etiology*; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes; D013952:Thymus Hyperplasia / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed
chemical_list: D005710:Gallium Radioisotopes; D013794:Thallium Radioisotopes