title: Technetium-99m-galactosyl-neoglycoalbumin combined with iodine-123-Tyr-(A14)-insulin visualizes human hepatocellular carcinomas.
abstract: Human hepatocellular carcinoma (HCC) is the most frequent primary hepatic malignancy and its diagnosis by conventional methods is still difficult. We hypothesized that the expression of specific receptors could possibly be used to improve in vivo localization of HCC with specific receptor-based radioligands.
  
  
  METHODS
  In initial in vitro studies, receptor binding of 99mTc-galactosyl-neoglycoalbumin (99mTc-NGA) and 123I-Tyr-(A14)-insulin to HCC was investigated. Scintigraphy was performed in 45 patients with histologically confirmed HCC using either 99mTc-NGA (75-150 MBq; 25-50 nmole, n = 27) and/or 123I-Tyr-(A14)-insulin (100-150 MBq; 7.5-10 micrograms, n = 30).
  
  
  RESULTS
  HCC (1256 +/- 290 pmole bound/mg protein, Kd = 3.4 +/- 2.9 nM) expressed a 1000-fold higher number of specific receptors for 123I-Tyr-(A14)-insulin compared to normal liver tissue (2.4 +/- 0.8 pmole bound/mg protein, Kd = 4.2 +/- 2.4 nM), whereas HCC did not express receptors specific for 99mTc-NGA. All HCC lesions were identified as cold spots after injection of 99mTc-NGA, whereas 123I-Tyr-(A14)-insulin accumulated in these lesions, indicating HCC-to-normal liver ratios of 1.6 +/- 0.4 in the mean. Subtraction images obtained from planar studies visualized 123I-Tyr-(A14)-insulin in HCC lesions detected by 99mTc-NGA as cold spots.
  
  
  CONCLUSIONS
  This hepatocyte receptor-specific, double-tracer method using 99mTc-NGA and 123I-Tyr-(A14)-insulin could become clinically useful in the diagnosis of HCC.
authors.affiliation: Department of Nuclear Medicine, University of Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Kurtaran
authors.forename: S R
authors.initials: SR
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Raderer
authors.forename: M
authors.initials: M
authors.lastname: Leimer
authors.forename: C
authors.initials: C
authors.lastname: Müller
authors.forename: J
authors.initials: J
authors.lastname: Pidlich
authors.forename: N
authors.initials: N
authors.lastname: Neuhold
authors.forename: P
authors.initials: P
authors.lastname: Hübsch
authors.forename: P
authors.initials: P
authors.lastname: Angelberger
authors.forename: W
authors.initials: W
authors.lastname: Scheithauer
mesh_terms: D000368:Aged; D000418:Albumins; D037263:Asialoglycoprotein Receptor; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D002352:Carrier Proteins / Q000032:analysis; D005260:Female; D006801:Humans; D007328:Insulin / Q000031:analogs & derivatives*; D007457:Iodine Radioisotopes; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D011877:Radionuclide Imaging; D011972:Receptor, Insulin / Q000032:analysis; D012680:Sensitivity and Specificity; D012709:Serum Albumin
chemical_list: D000418:Albumins; D037263:Asialoglycoprotein Receptor; D002352:Carrier Proteins; D007328:Insulin; D007457:Iodine Radioisotopes; D015609:Organotechnetium Compounds; D012709:Serum Albumin; C027122:hepatic sialoglycoprotein receptor; C036586:technetium Tc 99m neogalactoalbumin; C029491:insulin, 3-iodo-Tyr(A14)-; D011972:Receptor, Insulin