title: Thallium-201 scintigraphy to assess effect of chemotherapy in osteosarcoma.
abstract: Imaging results in patients with high-grade osteosarcoma of the extremities were reviewed to determine whether scintigraphic appearance correlated with histologic response to preoperative chemotherapy.
  
  
  METHODS
  Histologically, the percent tumor necrosis in specimens from 30 patients were classified into three grades: grade 1 = necrosis less than 60%, grade 2 = 60%-89% necrosis and grade 3 = diffuse necrosis greater than 90% based upon whole transverse sections. Scintigraphically, we analyzed 201TI uptake before and after preoperative chemotherapy. The changes in the tumor-to-background ratio were defined by an alteration ratio.
  
  
  RESULTS
  Of the 11 patients with a grade 1 response, the ratio showed -67.1% +/- 45.4% (mean +/- s.d.). Of the 9 patients with a grade 2 response, the ratio showed 37.9% +/- 29.9% of the 10 patients with a grade 3 response the ratio showed 105.5% +/- 12.4%. The ratios correlated well with the histologic grades (p < 0.0001; analysis of variance).
  
  
  CONCLUSIONS
  Thallium-201 scintigraphy accurately assesses the effect of chemotherapy on osteosarcoma.
authors.affiliation: Division of Nuclear Medicine, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ohtomo
authors.forename: S
authors.initials: S
authors.lastname: Terui
authors.forename: R
authors.initials: R
authors.lastname: Yokoyama
authors.forename: H
authors.initials: H
authors.lastname: Abe
authors.forename: T
authors.initials: T
authors.lastname: Terauchi
authors.forename: G
authors.initials: G
authors.lastname: Maeda
authors.forename: Y
authors.initials: Y
authors.lastname: Beppu
authors.forename: H
authors.initials: H
authors.lastname: Fukuma
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality; D017024:Chemotherapy, Adjuvant; D002648:Child; D005260:Female; D005266:Femoral Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000401:mortality; D006801:Humans; D008297:Male; D012516:Osteosarcoma / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality; D011877:Radionuclide Imaging; D013793:Thallium; D013794:Thallium Radioisotopes
chemical_list: D013794:Thallium Radioisotopes; C027549:thallium chloride; D013793:Thallium