title: Risk of thyroid malignancy following an index head and neck squamous cell carcinoma: A population-based study.
abstract: To evaluate the incidence of a subsequent primary thyroid malignancy in patients with an index head and neck squamous cell carcinoma (HNSCC), we analyzed the National Cancer Institute's Surveillance, Epidemiology, and End Results database to identify a cohort of patients who had been diagnosed with a primary HNSCC from 1973 through 2004. The study population was made up of 60,323 patients of all ages, roughly three-quarters of whom were male. A total of 60 patients (0.1%) developed a subsequent thyroid malignancy-not a statistically significant finding. The overall standard incidence ratio (SIR) for a subsequent thyroid malignancy was 1.58 (p < 0.05). The highest SIRs were seen during in the first 5 years after diagnosis of the original primary (SIR: 3.05; p < 0.05), more specifically in 2 to 11 months after diagnosis (SIR: 7.11; p < 0.05). Further analyses demonstrated that SIRs were significantly higher in males (SIR: 1.71), in patients aged 60 through 79 years (SIR: 1.71), in whites (SIR: 1.55), in patients who had undergone external-beam radiotherapy for their index primary (SIR: 1.84), in those whose tumor was initially staged as regional (SIR: 1.96), and in patients whose index primary was in the oral cavity (SIR: 1.71) or larynx (SIR: 1.88) (p < 0.05 for all). We conclude that the incidence of a subsequent primary thyroid malignancy in patients with an HNSCC is highest during the first 5 years after diagnosis of the index primary, reflecting the benefit of continued surveillance.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing Street, Shatin, Hong Kong SAR. jasonchan@ent.cuhk.edu.hk.
authors.forename: Jason Y
authors.initials: JY
authors.lastname: Chan
authors.forename: Zhen
authors.initials: Z
authors.lastname: Gooi
authors.forename: Wojciech K
authors.initials: WK
authors.lastname: Mydlarz
authors.forename: Nishant
authors.initials: N
authors.lastname: Agrawal
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D016208:Databases, Factual; D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors; D018426:SEER Program; D012737:Sex Factors; D000077195:Squamous Cell Carcinoma of Head and Neck; D013964:Thyroid Neoplasms / Q000453:epidemiology / Q000209:etiology*; D013997:Time Factors; D055815:Young Adult