RADIOPHARMACY
§ Radionuclide:131I t1/2: 8.1 days
§ Energies: 364 keV (g), 606 keV (b−)
§ Radiopharmaceutical:
§ 131I as sodium iodide capsule or liquid
§ Dose of radioiodine therapy:
§ * 30 – 80mCi 131I as ablative dose for residual thyroid
§ *120 – 150mCi 131I if cervical lymph nodes positive.
§ *150 – 200mCi 131I if metastatic lesions
Method of Administration: Oral (PO) capsule, through straw from
lead container for liquid.
Histopathology:
§ (1) Differentiated papillary & follicular cancer (90%).
§ (2) Medullary thyroid cancer (6%).
§ (3) Anaplastic cancer (4%).
§ (4) Other tumors (1%).
Investigation:
* Isotopic thyroid scan--------cold nodule.
* Ultrasound solid-----------versus cystic nodule.
* Fine needle aspiration cytology.
§ * Any patient received a dose > 30mCi should be hospitalized
in separate room.
§ * Patient should be fasting 2 – 4 hours before 131I therapy and
2 hours after therapy.
§ * Excess intake of fluid and suck of lemon wedges to decrease
radiation dose.
§ * No visitor except for few minutes (no pregnant or children).
§ * Food & drink in disposable containers.
§ * Chick room & laundry for contaminations.
• Ablation of residual functioning thyroid carcinoma.
• Ablation of residual functioning normal thyroid tissue after total
or partial thyroidectomy.
• Pregnancy or nursing.
• Allergy to iodine.
• Iodinated studies under way or performed recently.
• Patient taking thyroid medications or vitamins, or not on low-
iodine diet.
• Patient extremely likely to regurgitate dose.
RADIOPHARMACY
§ Radionuclide:131I t1/2: 8.1 days
§ Energies: 364 keV
§ Radiopharmaceutical: 131I-mIBG (-meta-iodobenzylguanidine).
§ Adult Dose Range: 131I: 500 μCi (18.5 MBq)
§ Method of Administration: Intravenous injected slowly over 5
minutes if possible.
§ EQUIPMENT
§ Camera: Large field of view.
§ Collimator: Medium energy, general purpose
§ Or medium energy, high resolution.
Laboratory finding:
§ * High thyroid function .
§ * Increased 131I uptake.
Scan finding:
§ * Diffuse homogeneous gland.
§ * Decrease background uptake.
§ * Prominent pyramidal lobe.
§ * Increased thyroid uptake.
vRadioactive iodine therapy
§ Dose calculation:
(A) Fixed dose: 10 – 15mCi of 131I.
(B) Multi nodular toxic goiter (Fig. 7.6 B):
§ Scan finding:
§ * Multiple hot and cold nodules.
§ * Suppression of the rest of the gland.
§ * High 131I uptake, high T3,T4.
§ * Main line of treatment is surgery.
§ * Radioiodine in larger doses 15 – 20mCi because of greater radio
resistance in nodular form with small range for β (1 – 2mm).
§ * Hypothyroidism in rare following 131I therapy in multi nodular
goiter.
(c) autonomous nodule (Fig. 7.6 C)
§ Scan findings:
§ * High radioactivity in the nodule suppressing the rest of gland.
§ * Higher doses of 131I therapy 20 – 30 mCi.
§ * Recovery of the remaining thyroid is seen following 131I
therapy.
§ Before Day of Injection
§ • Physician instructs the patient to take SSKI (saturated solution
potassium iodide) or Lugol’s solution to block free iodine uptake in
thyroid.This is administered 1 drop, t.i.d., beginning the day
before radiotracer administration and continuing for 6 days after
injection. If there is an allergy to iodine, perchlorate may be used.
§ • Physician instructs the patient to take bisacodyl (e.g., Dulcolax®)
10 mg PO, b.i.d. × 3 days before imaging, to reduce bowel activity.
Patient may be required to take laxatives and/or enemas on
afternoons before imaging days; check with radiologist.
§ • Physician instructs patients with atopic history (genetic
disposition to hypersensitivity or allergy to medications such as
iodine or steroids) to be treated with oral antihistamine (e.g.,
Benadryl® 50 mg)1 hour before injection of radiotracer.
§ Days of Injection
§ • Identify the patient.Verify doctor’s order. Explain the
procedure.
§ • Obtain signed consent from patient and a prescription for the
iodine.
§ • Ensure that the patient is not taking the following drugs:
steroids, antihypertensives, reserpine, tricyclic antidepressants,
sympathomimetics (adrenergic, stimulates release of
epinephrine), diuretics as per physician’s order. Ideally, no
medications for 2–3 weeks before the examination (see Drugs
to Withhold).
§ [standing] hypotension).These occur within the adrenal
medulla and are frequently associated
§ with hereditary multiple endocrine neoplasia (MEN)
types 2A and 2B, neurofibromatosis, von
§ Hippel-Lindau disease, Carney’s triad, and familial
pheochromocytoma.
§ • Localization of site(s) of hormonal overproduction.
§ • Detection and localization of neuroectodermal (nerve
tissue) tumors.
§ • Paragangliomas (tumors of the adrenal medulla,
chromaffin cells, and the paraganglia)
§ • Detection and localization of neuroblastomas
(malignant hemorrhagic tumors of cells resembling
neuroblasts of the sympathetic system, especially the
adrenal medulla, and usually occurring in childhood).
§ • Detection and localization of other neuroendocrine
tumors that share the property of amine precursor
uptake in decarboxylation (APUD), such as:
§ • Carcinoid (argentaffin cells of the intestinal tract, bile
ducts, pancreas, bronchus, or ovary that secrete
serotonin) tumors
§ Detection and localization of benign and malignant
intra-adrenal and extra-adrenal pheochromocytomas
(usually benign chromaffin cell tumors of the
sympathoadrenal system that produce andsecrete
catecholamines, e.g., norepinephrine and
epinephrine, producing hypertension and orthostatic
• Allergy to iodine may be a consideration, although doses are
small.
• Patient taking interfering medications.
Pre- MIBG
therapy
Post- MIBG
therapy
Carcinoid tumors :
Paragangliomas
Pre- MIBG
therapy
Post- MIBG
therapy
Reference :
- https://www.iaea.org/resources/rpop/health-professionals/nuclear-
medicine/therapeutic-nuclear-medicine
- Therapeutic Nuclear Medicine Editors Richard P. Baum
By : Maher alazmi

Therapeutic application

  • 2.
    RADIOPHARMACY § Radionuclide:131I t1/2:8.1 days § Energies: 364 keV (g), 606 keV (b−) § Radiopharmaceutical: § 131I as sodium iodide capsule or liquid § Dose of radioiodine therapy: § * 30 – 80mCi 131I as ablative dose for residual thyroid § *120 – 150mCi 131I if cervical lymph nodes positive. § *150 – 200mCi 131I if metastatic lesions Method of Administration: Oral (PO) capsule, through straw from lead container for liquid.
  • 3.
    Histopathology: § (1) Differentiatedpapillary & follicular cancer (90%). § (2) Medullary thyroid cancer (6%). § (3) Anaplastic cancer (4%). § (4) Other tumors (1%). Investigation: * Isotopic thyroid scan--------cold nodule. * Ultrasound solid-----------versus cystic nodule. * Fine needle aspiration cytology.
  • 4.
    § * Anypatient received a dose > 30mCi should be hospitalized in separate room. § * Patient should be fasting 2 – 4 hours before 131I therapy and 2 hours after therapy. § * Excess intake of fluid and suck of lemon wedges to decrease radiation dose. § * No visitor except for few minutes (no pregnant or children). § * Food & drink in disposable containers. § * Chick room & laundry for contaminations.
  • 5.
    • Ablation ofresidual functioning thyroid carcinoma. • Ablation of residual functioning normal thyroid tissue after total or partial thyroidectomy.
  • 6.
    • Pregnancy ornursing. • Allergy to iodine. • Iodinated studies under way or performed recently. • Patient taking thyroid medications or vitamins, or not on low- iodine diet. • Patient extremely likely to regurgitate dose.
  • 7.
    RADIOPHARMACY § Radionuclide:131I t1/2:8.1 days § Energies: 364 keV § Radiopharmaceutical: 131I-mIBG (-meta-iodobenzylguanidine). § Adult Dose Range: 131I: 500 μCi (18.5 MBq) § Method of Administration: Intravenous injected slowly over 5 minutes if possible. § EQUIPMENT § Camera: Large field of view. § Collimator: Medium energy, general purpose § Or medium energy, high resolution.
  • 8.
    Laboratory finding: § *High thyroid function . § * Increased 131I uptake. Scan finding: § * Diffuse homogeneous gland. § * Decrease background uptake. § * Prominent pyramidal lobe. § * Increased thyroid uptake.
  • 9.
    vRadioactive iodine therapy §Dose calculation: (A) Fixed dose: 10 – 15mCi of 131I. (B) Multi nodular toxic goiter (Fig. 7.6 B): § Scan finding: § * Multiple hot and cold nodules. § * Suppression of the rest of the gland. § * High 131I uptake, high T3,T4. § * Main line of treatment is surgery. § * Radioiodine in larger doses 15 – 20mCi because of greater radio resistance in nodular form with small range for β (1 – 2mm). § * Hypothyroidism in rare following 131I therapy in multi nodular goiter.
  • 10.
    (c) autonomous nodule(Fig. 7.6 C) § Scan findings: § * High radioactivity in the nodule suppressing the rest of gland. § * Higher doses of 131I therapy 20 – 30 mCi. § * Recovery of the remaining thyroid is seen following 131I therapy.
  • 12.
    § Before Dayof Injection § • Physician instructs the patient to take SSKI (saturated solution potassium iodide) or Lugol’s solution to block free iodine uptake in thyroid.This is administered 1 drop, t.i.d., beginning the day before radiotracer administration and continuing for 6 days after injection. If there is an allergy to iodine, perchlorate may be used. § • Physician instructs the patient to take bisacodyl (e.g., Dulcolax®) 10 mg PO, b.i.d. × 3 days before imaging, to reduce bowel activity. Patient may be required to take laxatives and/or enemas on afternoons before imaging days; check with radiologist. § • Physician instructs patients with atopic history (genetic disposition to hypersensitivity or allergy to medications such as iodine or steroids) to be treated with oral antihistamine (e.g., Benadryl® 50 mg)1 hour before injection of radiotracer.
  • 13.
    § Days ofInjection § • Identify the patient.Verify doctor’s order. Explain the procedure. § • Obtain signed consent from patient and a prescription for the iodine. § • Ensure that the patient is not taking the following drugs: steroids, antihypertensives, reserpine, tricyclic antidepressants, sympathomimetics (adrenergic, stimulates release of epinephrine), diuretics as per physician’s order. Ideally, no medications for 2–3 weeks before the examination (see Drugs to Withhold).
  • 14.
    § [standing] hypotension).Theseoccur within the adrenal medulla and are frequently associated § with hereditary multiple endocrine neoplasia (MEN) types 2A and 2B, neurofibromatosis, von § Hippel-Lindau disease, Carney’s triad, and familial pheochromocytoma. § • Localization of site(s) of hormonal overproduction. § • Detection and localization of neuroectodermal (nerve tissue) tumors. § • Paragangliomas (tumors of the adrenal medulla, chromaffin cells, and the paraganglia)
  • 15.
    § • Detectionand localization of neuroblastomas (malignant hemorrhagic tumors of cells resembling neuroblasts of the sympathetic system, especially the adrenal medulla, and usually occurring in childhood). § • Detection and localization of other neuroendocrine tumors that share the property of amine precursor uptake in decarboxylation (APUD), such as: § • Carcinoid (argentaffin cells of the intestinal tract, bile ducts, pancreas, bronchus, or ovary that secrete serotonin) tumors § Detection and localization of benign and malignant intra-adrenal and extra-adrenal pheochromocytomas (usually benign chromaffin cell tumors of the sympathoadrenal system that produce andsecrete catecholamines, e.g., norepinephrine and epinephrine, producing hypertension and orthostatic
  • 16.
    • Allergy toiodine may be a consideration, although doses are small. • Patient taking interfering medications.
  • 17.
  • 19.
  • 21.