Radiation and Second Primary Thyroid Cancer Following Index Head and Neck Cancer.


Journal Article

OBJECTIVES/HYPOTHESIS: Radiation is thought to increase risk of developing second primary thyroid cancer (SPTC). This study estimated the rate of SPTC following index head and neck cancer (HNC) and determined whether radiation treatment among HNC survivors increased SPTC risk. STUDY DESIGN: Retrospective data analysis. METHOD: The Surveillance, Epidemiology, and End Results database (1975-2014) was queried for cases of index HNC (N = 127,563) that developed SPTC. Adjusted multivariable competing risk proportional hazards model tested risk of developing a SPTC following index HNC. Sensitivity analyses using proportional hazards models were also performed restricting data to patients who 1) received both radiation and chemotherapy and 2) radiation alone. RESULTS: Only 0.2% of index HNC survivors (n = 229) developed SPTC, yielding a rate of 26.1 per 100,000 person-years. For every increasing year of age at diagnosis, patients were 3% less likely to develop an SPTC (adjusted hazard ratio [aHR] = 0.97, 95% CI: 0.96-0.98). Males were also less likely to develop an SPTC (aHR = 0.73, 95% CI: 0.55-0.96). Radiation (aHR = 0.92, 95% CI: 0.68-1.25), surgery (aHR = 0.79, 95% CI: 0.56-1.11), and chemotherapy (aHR = 1.13, 95% CI: 0.76-1.69) were not significantly associated with developing SPTC. The sensitivity models also did not find an association between treatment and risk of SPTC. CONCLUSIONS: Rate of developing SPTC following index HNC was very low, and previous exposure to radiation did not significantly increase risk in our study population. More studies are needed to understand the increasing incidence of thyroid cancer across the United States. LEVEL OF EVIDENCE: NA Laryngoscope, 129:1014-1020, 2019.

Full Text

Duke Authors

Cited Authors

  • Polednik, KM; Simpson, MC; Adjei Boakye, E; Mohammed, KA; J Dombrowski, J; Varvares, MA; Osazuwa-Peters, N

Published Date

  • April 2019

Published In

Volume / Issue

  • 129 / 4

Start / End Page

  • 1014 - 1020

PubMed ID

  • 30208210

Pubmed Central ID

  • 30208210

Electronic International Standard Serial Number (EISSN)

  • 1531-4995

Digital Object Identifier (DOI)

  • 10.1002/lary.27467


  • eng

Conference Location

  • United States