[Radioiodine therapy of differentiated thyroid cancer: radiologic impact of out-patient treatment with 100 to 150 mCi Iodine-131 activities].
OBJECTIVE
To evaluate exposure and dosimetry to family members and environment due to outpatient radioiodine therapy of differentiated thyroid carcinoma.


METHODS
Twenty patients were treated with 100-150mCi of iodine-131 on an out-patient basis. Family members dosimetry (n = 27) and potential doses inside the house were measured with thermoluminescent dosimeters. Surface contamination and radioactive wastes were also monitored.


RESULTS
Less than 1.0 mSv doses were found in 26 co-habitants and 2.8 mSv in a single case (inferior to the acceptable value of 5.0 mSv/procedure). Potential doses in the houses were inferior to 0.25 mSv, excluding the patients bedroom (mean value = 0.69 mSv). Surface contamination (mean = 4.2 Bq.cm-2) were below clearance levels. Radioactive wastes generated had a volume of 2.5 liters and a total activity estimated in 90 microCi, with a calculated exposure close to the background radiation levels.


CONCLUSIONS
No radiological impact was detected after iodine therapy with 100-150 mCi on an out-patient basis followed by experienced professionals.
Sapienza
Marcelo Tatit
MT
Serviço de Medicina Nuclear, Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo (FMUSP), São Paulo, SP, Brasil. mtsapienza@hotmail.com
Willegaignon
José
J
Ono
Carla Rachel
CR
Watanabe
Tomoco
T
Guimarães
Maria Inês Calil Cury
MI
Gutterres
Ricardo Fraga
RF
Maréchal
Maria Helena da Hora
MH
Buchpiguel
Carlos Alberto
CA
D000328:Adult; D000553:Ambulatory Care; D004781:Environmental Exposure / Q000517:prevention & control*; D005190:Family; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D011835:Radiation Protection / Q000379:methods* / Q000592:standards; D011879:Radiotherapy Dosage; D013819:Thermoluminescent Dosimetry; D013964:Thyroid Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D013965:Thyroidectomy
D007457:Iodine Radioisotopes