1、Radioiodinated MIBG treatment of pheochromocytomaPheochromocytomalOriginate from chromaffin cells(嗜铬细胞）嗜铬细胞）l90%located in adrenal medulla（肾上腺髓质）（肾上腺髓质）lProducing and releasing catecholamines（儿茶（儿茶酚胺）酚胺）lead to paroxysmal（陈发性）（陈发性）or persistent hypertension and other symptoms.l10-20%of pheochromocyt
2、oma is malignancy（恶性）（恶性）Diagnosis lbiochemical studies urinary and blood test：catecholamines，catecholamine metabolites lImaging techniques CT and MRI:highly sensitive,nonspecific MIBG scanning:highly specific,less sensitive TreatmentlThe primary management of pheochromocytoma tumors is surgical lCh
3、emotherapy and radiotherapy is less work to malignant pheochromocytomalMIBG is selectively concentrated by these tumours.131I-labelled MIBG is used as a therapy for MIBG avid tumours.PrinciplelRadioiodinated MIBG is a guanethidine（胍乙啶胍乙啶）analog,structurally similar to norepinephrine（去（去甲肾上腺素）甲肾上腺素）.
4、lIt is concentrated in the adrenal medulla（肾上腺（肾上腺髓质）髓质）and adrenergic neurons（肾上腺素能神经元）（肾上腺素能神经元）predominantly.lPheochromocytoma is selectively uptake 131I-MIBG.lBeta radiation emitted from131I-MIBG destroy the cancer cells.IndicationlDisseminated disease（播散病灶）（播散病灶）lUnresectable pheochromocytoma（不
5、能手术切（不能手术切除的病灶）除的病灶）lPost-surgical residual tumors were also treated with the purpose of complementing surgery ContraindicationlPregnant or breast feedinglWBC4.0X109,RBC3.5X109,PLT9X109lKidney failureProcedure for 131I-MIBG l131I-MIBG imaging study to dosimetric estimates.lStop drug known to reduce
6、MIBG uptake and/or retention 7days before treatment.lThyroid blockade with lugols solution(复方碘溶复方碘溶液）液）l131I-MIBG infusion for 2 hours with continuous pulse,BP and ECG monitoring.lPost-therapy scintigraphic imaging studieslWeekly full blood counts as well as hepatic and renal tests for at least 6 we
7、ekslAssessment of response using combined CT/MRI/bone scan/MIBG imaging before the subsequent course.Therapeutic dosageFixed dose 100-300mCiEstimated byl131IMIBG tumoral uptake lretention of the tracer dose lthe volume of the tumor Retreat 4-12 month intervalSide effectlshort-term side effects nause
8、a and anorexia（恶性及纳差（恶性及纳差）vomitting（呕吐）（呕吐）rise in blood pressurellong term side effects low bone marrow depression Efficacy evaluationl95%Pheochromocytoma is able to uptake 131I MIBGlPurpose of treatment include:symptom palliation tumor function reduction tumor arrest tumor regression leffective p
9、ower is 70%Normal 131 I-MIBG anterior and posterior whole body scanshowing physiological salivary gland,myocardial and hepatic uptake with renal and gastrointestinal excretion.131 I-MIBG is also usually taken up by the adrenal glands.Summaryl131I-MIBG is an effective and safe treatment modality.l Treatment with multiple doses is well-tolerated and generally leads to symptomatic relief.l it has little toxicity.Thank you!
