The objectives of our study were to determine whether central tumor photopenia on thallium-201 (201Tl) scintigraphy of primary osteosarcoma results from central tumor necrosis or dense central tumor ossification and to determine the relation of this finding to tumor response to chemotherapy and to patient survival.
Department of Radiological Sciences, Division of Diagnostic Imaging, St. Jude Children's Research Hospital, 332 N Lauderdale St., Memphis, TN 38105-2974, USA. Beth.McCarville@stjude.org