title: [Application of 13-cis-retinoic acid in patients with 131I scintigraphically-negative metastases of differentiated thyroid carcinoma].
abstract: BACKGROUND
  The loss of iodine uptake by differentiated thyroid carcinoma (DTC) cells is a major therapeutic problem especially in patients with nonsurgical metastatic foci or local recurrence. Using 13-cis-retinoic acid, it was attempted to retain iodine uptake as a result of redifferentiation (influence by retinoic acid receptors present in DTC cells).
  
  
  METHODS
  Between 1999 and 2005, 13-cis-retinoic acid was used in 11 patients with disseminated PTC and high serum level of thyroglobulin (Tg) before (131)I treatment (2 patients were treated twice - 13 treatment cycles in total). Side effects in skin and mucous membranes were observed in all the patients, however, their intensity did not require termination of the therapy.
  
  
  RESULTS
  Increase of iodine uptake was observed in 5 patients (45%). Decreased Tg concentration was observed in 9 patients. In that group, increased (131)I uptake was observed in 4 patients with distant metastases. All determinations of Tg concentrations were carried out under TSH stimulation.
  
  
  CONCLUSIONS
  13-cis-retinoic acid causes an increase of radioiodine uptake in around half of treated patients, however, the follow-up of these patients indicates that this increase does not result in either full remission or even stabilisation of neoplastic disease. The possibility should be considered to use cis-retinoic acid as an independent therapeutic approach in patients with radioiodine non-avid foci of thyroid carcinoma especially those showing high expression of RARb and RXRg receptors.
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Unit of Nuclear Medicine and Oncological Endocrinology Medical University, Lodz.
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Adamczewski
authors.forename: Jacek
authors.initials: J
authors.lastname: Makarewicz
authors.forename: Sławomir
authors.initials: S
authors.lastname: Mikosiński
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Knapska-Kucharska
authors.forename: Anna
authors.initials: A
authors.lastname: Gunerska-Szadkowska
authors.forename: Lidia
authors.initials: L
authors.lastname: Oszukowska
authors.forename: Anzelmina
authors.initials: A
authors.lastname: Karwowska
authors.forename: Andrzej
authors.initials: A
authors.lastname: Lewiński
mesh_terms: D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000188:drug therapy* / Q000532:radiotherapy* / Q000556:secondary; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D015474:Isotretinoin / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy; D011877:Radionuclide Imaging; D013954:Thyroglobulin / Q000097:blood; D013964:Thyroid Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy* / Q000556:secondary; D016896:Treatment Outcome; D014915:Whole-Body Counting
chemical_list: D007457:Iodine Radioisotopes; D013954:Thyroglobulin; D015474:Isotretinoin