ENDOCRINOLOGY - II
Therapy 

The Quarterly Journal of Nuclear Medicine 1999 December;43(4):324-35

Copyright © 2000 EDIZIONI MINERVA MEDICA

lingua: Inglese

131I therapy of thyroid cancer patients

Reiners C., Farahati J.

From the Clinic for Nuclear Medicine University of Wuerzburg, Germany

Thyroid can­cer is a ­rare malig­nan­cy ­with ­wide inter­eth­nic and geo­graph­ic vari­a­tions. In Germany thy­roid car­ci­no­ma is the 13th ­most fre­quent malig­nan­cy (2.7 new cas­es year­ly per 100,000 inhab­i­tants). The over­all tem­po­ral inci­dence is increas­ing slight­ly in ­recent ­years. The ­most com­mon ­types of can­cer are pap­il­lary (60-80%) and fol­lic­u­lar can­cers (10-20%). The rel­e­vant prog­nos­tic indi­ca­tors are ­tumor ­stage and dis­tant metas­ta­ses. The ­mean sur­vi­val ­rates in pap­il­lary thy­roid can­cer usu­al­ly ­exceed 90%, where­as in fol­lic­u­lar thy­roid can­cer ­they ­amount to approx­i­mate­ly 80%. The stan­dard treat­ment pro­ce­dure in dif­fer­en­tiat­ed pap­il­lary and fol­lic­u­lar thy­roid can­cer con­sists of ­total thy­roi­dec­to­my fol­lowed by adju­vant abla­tive ther­a­py ­with radio­io­dine. Only in pap­il­lary thy­roid can­cer ­stage pT1N0M0 lobec­to­my ­alone is con­sid­ered to be appro­pri­ate. In ­patients ­with local­ly inva­sive dif­fer­en­tiat­ed thy­roid can­cers ­stage pT4 adju­vant per­cut­ane­ous radi­a­tion ther­a­py is a treat­ment ­option. Radioiodine the-r­a­py has to be per­formed ­under the stim­u­la­tive influ­ence of TSH. Usually TSH sup­pres­sive med­i­ca­tion ­with Levothy­rox­ine has to be with­drawn approx­i­mate­ly 4 ­weeks ­prior to radio­io­dine ther­a­py. In the ­future, exog­e­nous stim­u­la­tion by recom­bi­nant TSH may be ­used ­instead of thy­roid hor­mone with­draw­al. It has ­been prov­en by dif­fer­ent stud­ies ­that abla­tive radio­io­dine ther­a­py reduc­es the fre­quen­cy of recur­renc­es and ­tumor ­spread in ­patients ­with thy­roid can­cer sig­nif­i­cant­ly. In ­patients ­with dis­tant metas­ta­ses, up to 50% of com­plete ­responses may be ­achieved ­with radio­io­dine treat­ment.