Timing of Adjuvant Radioactive Iodine Therapy Does Not Affect Overall Survival in Low- and Intermediate-Risk Papillary Thyroid Carcinoma.
There is no consensus regarding the timing of adjuvant radioactive iodine therapy (RAI) therapy in low- and intermediate-risk papillary thyroid carcinoma (PTC). We analyzed the impact of adjuvant RAI on overall survival (OS) in low- and intermediate-risk PTC. The National Cancer Data Base was queried from 2004 to 2011 for pN0M0 PTC patients having near/subtotal or total thyroidectomy and adjuvant RAI. Tumors ≤1 cm with negative margins were low risk while 1.1- to 4-cm tumors with negative margins or ≤1 cm with microscopic margins were termed intermediate risk. RAI in ≤3 months and between 3 and 12 months was termed as early and delayed, respectively. Survival analysis was performed after adjusting for patient and tumor-related variables. There were 7,306 low-risk and 16,609 intermediate-risk patients. Seventeen per cent low-risk and 15 per cent intermediate-risk patients had delayed RAI. Kaplan-Meier analysis did not show a difference in OS for early versus delayed RAI administration in low- (10-year OS 94.5% vs 94%, P = 0.627) or intermediate-risk (10-year OS 95.3% vs 95.9%, P = 0.944) patients. In adjusted survival analysis, RAI timing did not affect OS in all patients (hazard ratios = 0.98, 95% confidence interval = 0.71-1.34, P = 0.887). In conclusion, the timing of postthyroidectomy adjuvant RAI therapy does not affect OS in low- or intermediate-risk PTC.
Department of Surgery, NorthShore University Health System-University of Chicago, Evanston, Illinois, USA.
Paritosh
P
Suman
Chi-Hsiung
CH
Wang
Tricia A
TA
Moo-Young
Richard A
RA
Prinz
David J
DJ
Winchester
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D002291:Carcinoma, Papillary; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage* / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals / Q000008:administration & dosage* / Q000627:therapeutic use; D018714:Radiotherapy, Adjuvant; D012306:Risk; D016019:Survival Analysis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D013965:Thyroidectomy; D013997:Time Factors; D016896:Treatment Outcome
D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals