title: Comparison of different dosimetric methods for red marrow absorbed dose calculation in thyroid cancer therapy.
abstract: Several dosimetric methods have been proposed for estimating red marrow absorbed dose (RMAD) when radionuclide therapy is planned for differentiated thyroid cancer, although to date, there is no consensus as to whether dose calculation should be based on blood-activity concentration or not. Our purpose was to compare RMADs derived from methods that require collecting patients' blood samples versus those involving OLINDA/EXM software, thereby precluding this invasive procedure. This is a retrospective study that included 34 patients under treatment for metastatic thyroid disease. A deviation of <10 % between RMADs was found, when comparing the doses from the most usual invasive dosimetric methods and those from OLINDA/EXM. No statistical difference between the methods was discovered, whereby the need for invasive procedures when calculating the dose is questioned. The use of OLINDA/EXM in clinical routine could possibly diminish data collection, thus giving rise to a simultaneous reduction in time and clinical costs, besides avoiding any kind of discomfort on the part of the patients involved.
authors.affiliation: Nuclear Medicine Center, Department of Radiology, School of Medicine, University of São Paulo, São Paulo, Brazil. willegaignon@hotmail.com
authors.forename: José
authors.initials: J
authors.lastname: Willegaignon
authors.forename: Marcelo T
authors.initials: MT
authors.lastname: Sapienza
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Buchpiguel
mesh_terms: D000042:Absorption; D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000378:metabolism* / Q000528:radiation effects; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012984:Software; D013964:Thyroid Neoplasms / Q000532:radiotherapy* / Q000556:secondary
chemical_list: D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals