title: Is it necessary to reduce the radioiodine dose in patients with thyroid cancer and renal failure?
abstract: The objective of this study were to obtain dosimetric data from a patient with thyroid cancer simultaneously undergoing peritoneal dialysis therapy, so as to determine the appropriate amount of 131I activity to be applied therapeutically. Percentages of radioiodine in the blood and the whole-body were evaluated, and radiation absorbed doses were calculated according to OLINDA/EXM software. Whole-body 131I effective half-time was 45.5 hours, being four times longer than for patients without any renal dysfunction. Bone-marrow absorbed dose was 0.074 mGy/MBq, with ablative procedure maintenance at 3.7 GBq, as the reported absorbed dose was insufficiently restrictive to change the usual amount of radioiodine activity administered for ablation. It was concluded that radioiodine therapeutic-dose adjustment, based on individual patient dosimetry, is an important way of controlling therapy. It also permits the safe and potential delivery of higher doses of radiation to tumors and undesirable tissues, with a minimum of malignant effects on healthy tissues.
authors.affiliation: Departamento de Radiologia, Universidade de São Paulo, SP, Brazil. willegaignon@hotmail.com
authors.forename: José
authors.initials: J
authors.lastname: Willegaignon
authors.forename: Verena Pinto Brito
authors.initials: VP
authors.lastname: Ribeiro
authors.forename: Marcelo
authors.initials: M
authors.lastname: Sapienza
authors.forename: Carla
authors.initials: C
authors.lastname: Ono
authors.forename: Tomoco
authors.initials: T
authors.lastname: Watanabe
authors.forename: Carlos
authors.initials: C
authors.lastname: Buchpiguel
mesh_terms: D001853:Bone Marrow / Q000528:radiation effects; D002291:Carcinoma, Papillary / Q000532:radiotherapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000379:methods; D057285:Precision Medicine; D011879:Radiotherapy Dosage; D051437:Renal Insufficiency / Q000628:therapy*; D013964:Thyroid Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D051598:Whole Body Imaging
chemical_list: D007457:Iodine Radioisotopes