title: Iodine isotope ¹³¹I therapy for toxic nodular goitre: treatment efficacy parameters.
abstract: BACKGROUND
  When planning radioactive iodine therapy, it frequently happens, both in Poland and world-wide, that inadequate attention is paid to such easily measurable parameter sas: 1) the serum concentration of thyrotropin (TSH) before administering radioiodine, which is a key factor for extranodular(non-autonomous) iodine uptake of the thyroid gland, 2) thyroid gland iodine uptake, and 3) the effective half-life of 131I (Teff.). The aim of the study is to evaluate the impact of the above factors on the efficacy of 131I treatment in hyperthyroid patients.
  
  
  METHODS
  The material consisted of 4140 patients: 2190 with autonomous toxic nodules (ATN) and 1950 with toxic multinodular goitres (TMG). The patients were prepared for treatment in such a way that the concentration of TSH did not exceed 0.1 mU/land Teff.< 5 days. The therapeutic activity of 131I was calculated using Marinelli's formula. The selection of absorbed dose value was determined by the degree of suppression of extranodulart issue. Monitoring was performed every eight weeks.
  
  
  RESULTS
  At one year after 131I administration showed that a euthyroid status was achieved in 94%, hypothyroidism was seen observed in 3%, while persistence or recurrence of hyperthyroidism in 3% of ATN patients and, respectively, 89%, 4% and 7% of TMG patients.
  
  
  CONCLUSIONS
  Patients with toxic nodular goitre who are to be treated with radioiodine should have the lowest possible serum concentration of TSH. The suppression of extranodular determines the optimal value of absorbed dose for Marinelli's formula.
authors.affiliation: Nuclear Medicine Department, ul. Waszyngtona 13, 15–269 Białystok. piotrmjs@wp.pl
authors.forename: Piotr
authors.initials: P
authors.lastname: Szumowski
authors.forename: Franciszek
authors.initials: F
authors.lastname: Rogowski
authors.forename: Saeid
authors.initials: S
authors.lastname: Abdelrazek
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Kociura-Sawicka
authors.forename: Anna
authors.initials: A
authors.lastname: Sokolik-Ostasz
mesh_terms: D000328:Adult; D005260:Female; D006044:Goiter, Nodular / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D006801:Humans; D006980:Hyperthyroidism / Q000000981:diagnostic imaging / Q000532:radiotherapy; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D016606:Thyroid Nodule / Q000000981:diagnostic imaging / Q000532:radiotherapy; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D007457:Iodine Radioisotopes