title: Measurement of serum PDN-21 (Katacalcin) levels by radioimmunoassay in patients with various thyroid diseases.
abstract: We established a radioimmunoassay (RIA) using anti-PDN-21 antiserum, which was obtained by immunizing rabbits with synthesized PDN-21, and the basic results are described in this report, with discussion of the significance of PDN-21 determination in various thyroid diseases. In this RIA, the double antibody technique was used for B/F separation. This assay yielded excellent standard curves, specificity, recovery and reproducibility showing that the assay is satisfactory from the clinical standpoint. The upper limit of the normal PDN-21 level was 67 pg/ml in 98 healthy persons. Only patients with medullary carcinoma of the thyroid among patients with various thyroid diseases showed specifically positive assay results. The level was 110 to 18,300 pg/ml (mean, 5,940 pg/ml) in 7 patients whose levels were determined preoperatively, and 64 to 140,000 pg/ml (mean, 10,900 pg/ml) in 18 patients whose levels were determined postoperatively. Thus, PDN-21 levels increased very sharply in the settings of recurrence and tumor residue. These results suggest that PDN-21 has the potential to be an extremely sensitive, highly specific marker for medullary carcinoma of the thyroid.
authors.affiliation: First Department of Surgery, Teikyo University, School of Medicine, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Takami
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000097:blood; D000236:Adenoma / Q000097:blood; D000328:Adult; D002116:Calcitonin / Q000097:blood*; D018276:Carcinoma, Medullary / Q000097:blood; D002291:Carcinoma, Papillary / Q000097:blood; D005260:Female; D006042:Goiter / Q000097:blood; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000097:blood*; D011863:Radioimmunoassay; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013959:Thyroid Diseases / Q000097:blood*; D013964:Thyroid Neoplasms / Q000097:blood; D013966:Thyroiditis / Q000097:blood
chemical_list: D010446:Peptide Fragments; C037553:katacalcin; D002116:Calcitonin