核医学教学课件：Iodine-131 treatment for Differentiated Thyroid Carcinoma.ppt

Iodine-131 treatment for Differentiated Thyroid Carcinoma Thyrid cancer Papillary thyroid carcinoma Follicular thyroid carcinoma Others: medullary thyroid cancer, anaplastic thyroid cancer. EtiologyPrior exposure to radiationDietary factorsGenetic ,endocrine and immunity Clinical featuresSolitary thyroid nodule in anterior cervical triangle. To be discovered by accident or on routine physical examination . Painless and moves druing deglutition DiagnosisFine-needle aspiration of thyroid nodules Thyroid radioactive scan Ultrasound CT or MRIpathology TreatmentSurgical therapyiodine-131 therapythyroidhormone TreatmentSurgery is to clear up primary lesion,most normal thyroid tissue and regional metastases. 131I is to ablate the remnant thyroid tissue and metastases Lifelong thyroid hormone replacement is to prevent hypothyroidism and relapse PrincipleThyroid gland accumulate 131I .Well differentiated thyroid cancers can take up 131I .The β-radiation destroy those cancer lesions. Why do patients need 131I therapy? There are still some minimum cancers in the remnant thyroid tissue .If we ablate the remnant tissue ,it is better to find metastases . Examine the level of thyroglobulin .Higher ablation dose detect remnant or metastases better than diagnostic dose. Whole body scan after first 131I therapy Whole body scan after second 131I therapy Whole body scan with 10 mCi 131I Whole body scan with 150 mCi 131I procedure of 131I therapy131I ablate remnant thyroid tissue131I treat metastases 131I ablate remnant thyroid tissue Indication 131I ablation is used in patients who undergo thyorid surgery.131I uptake is above 1% Thyroid image show the remnant thyroid tissue. Therapeutic methodsPatients should have low-iodine diet to double the 131I uptake. Stop thyroid hormone for 4-6 weeks.131I ablation is better to start in 4-6weeks later after surgery. To examine the thyroid function, X-ray,131I uptake,liver function,kidney function ect. Therapeutic methodsGive