Redifferentiation therapy with 13-cis retinoic acids in radioiodine-resistant thyroid cancer.
Radioiodine (I-131) therapy is of proven efficacy for treatment of differentiated thyroid carcinoma (DTC). However, loss of differentiation in recurrent or metastatic DTC which decrease I-131 uptake may decrease the efficacy of I-131 therapy. Therefore, strategies to improve I-131 uptake are mandatory. This study is an open label clinical study to evaluate the effectiveness of 13-cis retinoic acid (13-cis RA) for improving I-131 uptake in recurrent or metastatic of DTC with defective I-131 uptake. Eleven patients (Age 27-66 years, M : F=4 : 7) were given 13-cis RA (1.5 mg/kg daily for 5 weeks), followed by 200 mCi (7.4 GBq) I-131 treatment. The differences of serum thyroglobulin (Tg) level and I-131 uptake on the post-treatment whole body scan (RxWBS) were compared before and after 13-cis RA therapy. Six out of 11 patients showed significantly increased (above 50%) Tg levels just after RA therapy. However, Tg levels a year after I-131 therapy were increased, stable and decreased in 7, 2 and 1 patients, respectively. Iodine uptake on RxWBS showed marginal improvement in only 2 patients and their Tg levels after one year follow-up increased. Most frequent adverse events were dry skin and lips. 13-cis RA partially restores I-131 uptake in few patients with recurrent or metastatic DTC. The use of 13-cis RA in current protocol has only limited usefulness and is not routinely recommended as currently used protocol.
Department of Endocrinology & Metabolism, University of Ulsan College of Medicine, Seoul, Korea.
Won Gu
WG
Kim
Eui Young
EY
Kim
Tae Yong
TY
Kim
Jin-Sook
JS
Ryu
Suck Joon
SJ
Hong
Won Bae
WB
Kim
Young Kee
YK
Shong
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D018265:Carcinoma, Papillary, Follicular / Q000188:drug therapy* / Q000532:radiotherapy*; D002454:Cell Differentiation / Q000187:drug effects; D017024:Chemotherapy, Adjuvant / Q000379:methods; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D015474:Isotretinoin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D013964:Thyroid Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D017211:Treatment Failure; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D007457:Iodine Radioisotopes; D015474:Isotretinoin