title: Correlation of the findings of thallium-201 chloride scans with those of other imaging modalities and histology following therapy in patients with bone and soft tissue sarcomas.
abstract: We performed a retrospective [corrected] study to evaluate the imaging potential of thallium-201 as compared with other imaging modalities in differentiating residual/recurrent tumors from post-therapy changes in patients with musculoskeletal sarcomas. 201Tl scans, magnetic resonance imaging (17), X-ray computed tomography (6) or contrast angiography (6) studies in 29 patients previously treated for musculoskeletal sarcomas were correlated with either histopathologic findings (26 patients) or 2-year clinical follow-up (three patients). All imaging studies were acquired within 2 weeks. Ratios of 201Tl tumor uptake to the contralateral (28 patients) or adjacent region of interest were calculated. When qualitative interpretation was in doubt, only those cases with a ratio of 1.5 or more were considered suggestive of recurrent of residual viable tumor tissue. Residual or recurrent tumor tissue was verified in 21 patients by biopsy. All had true-positive 201Tl scans while the other imaging modalities were true-positive in 20 and equivocal in one. In eight patients, there was no evidence of viable tumor tissue as proven by biopsy in five and long-term clinical follow-up in three. 201Tl scan was false-positive (ratio 1.5) in one patient and true-negative in seven while the other imaging modalities had four false-positives. The average 201Tl ratios were 2.8+/-1.1 in the true-positive cases and 1.3+/-0.3 in the true-negative cases. The percentage sensitivities, specificities, and accuracy for 201Tl were 100%, 87.5%, and 96.5% versus 95%, 50%, and 82.7% respectively for other imaging modalities. These results indicate that 201Tl scintigraphy is more accurate than other imaging modalities in differentiating residual/recurrent musculoskeletal sarcomas from post-therapy changes.
authors.affiliation: Nuclear Medicine Service, Memorial Sloan-Kettering Cancer Center, New York, USA.
authors.forename: L
authors.initials: L
authors.lastname: Kostakoglu
authors.forename: D M
authors.initials: DM
authors.lastname: Panicek
authors.forename: C R
authors.initials: CR
authors.lastname: Divgi
authors.forename: J
authors.initials: J
authors.lastname: Botet
authors.forename: J
authors.initials: J
authors.lastname: Healey
authors.forename: S M
authors.initials: SM
authors.lastname: Larson
authors.forename: H M
authors.initials: HM
authors.lastname: Abdel-Dayem
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D009364:Neoplasm Recurrence, Local; D018365:Neoplasm, Residual; D011446:Prospective Studies; D012509:Sarcoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012680:Sensitivity and Specificity; D013793:Thallium; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D013794:Thallium Radioisotopes; C027549:thallium chloride; D013793:Thallium