OBJECTIVE: To obtain more precise estimates of the association between thyroid cancer and benign thyroid diseases and to elucidate the role of potential confounders or effect modifiers. METHODS: The original data from 12 case-control studies from the United States, Asia, and Europe were pooled. Based on 2,094 women and 425 men with cancer of the thyroid and, respectively, 3,248 and 928 control subjects, odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained by conditional regression models, conditioning on study and age at diagnosis, and adjusting for age and radiotherapy. RESULTS: A history of hypothyroidism was not associated with cancer risk (pooled ORs = 0.9, 95% confidence interval, CI: 0.7-1.3 in women and 1.7, 95% CI: 0.3-11.7 in men). ORs for hyperthyroidism were 1.4 (95% CI: 1.0-2.1) in women and 3.1 (95% CI: 1.0-9.8) in men. In women, however, risk was lower in the absence of or after allowance for history of goiter. Pooled ORs for a history of goiter were 5.9 (95% CI: 4.2-8.1) in women and 38.3 (95% CI: 5.0-291.2) in men. Risk for a history of benign nodules/adenomas was especially high (OR = 29.9, 95% CI: 14.5-62.0, in women; 18 cases versus 0 controls in men). The excess risk for goiter and benign nodules/adenomas was greatest within 2-4 years prior to thyroid cancer diagnosis, but an elevated OR was present 10 years or more before cancer. CONCLUSIONS: Goiter and benign nodules/adenomas are the strongest risk factors for thyroid cancer, apart from radiation in childhood.
OBJECTIVE: To obtain more precise estimates of the association between thyroid cancer and benign thyroid diseases and to elucidate the role of potential confounders or effect modifiers. METHODS: The original data from 12 case-control studies from the United States, Asia, and Europe were pooled. Based on 2,094 women and 425 men with cancer of the thyroid and, respectively, 3,248 and 928 control subjects, odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained by conditional regression models, conditioning on study and age at diagnosis, and adjusting for age and radiotherapy. RESULTS: A history of hypothyroidism was not associated with cancer risk (pooled ORs = 0.9, 95% confidence interval, CI: 0.7-1.3 in women and 1.7, 95% CI: 0.3-11.7 in men). ORs for hyperthyroidism were 1.4 (95% CI: 1.0-2.1) in women and 3.1 (95% CI: 1.0-9.8) in men. In women, however, risk was lower in the absence of or after allowance for history of goiter. Pooled ORs for a history of goiter were 5.9 (95% CI: 4.2-8.1) in women and 38.3 (95% CI: 5.0-291.2) in men. Risk for a history of benign nodules/adenomas was especially high (OR = 29.9, 95% CI: 14.5-62.0, in women; 18 cases versus 0 controls in men). The excess risk for goiter and benign nodules/adenomas was greatest within 2-4 years prior to thyroid cancer diagnosis, but an elevated OR was present 10 years or more before cancer. CONCLUSIONS:Goiter and benign nodules/adenomas are the strongest risk factors for thyroid cancer, apart from radiation in childhood.
Authors: Catherine C Lerro; Laura E Beane Freeman; Curt T DellaValle; Muhammad G Kibriya; Briseis Aschebrook-Kilfoy; Farzana Jasmine; Stella Koutros; Christine G Parks; Dale P Sandler; Michael C R Alavanja; Jonathan N Hofmann; Mary H Ward Journal: Occup Environ Med Date: 2017-08-03 Impact factor: 4.402
Authors: Catherine C Lerro; Stella Koutros; Gabriella Andreotti; Melissa C Friesen; Michael C Alavanja; Aaron Blair; Jane A Hoppin; Dale P Sandler; Jay H Lubin; Xiaomei Ma; Yawei Zhang; Laura E Beane Freeman Journal: Occup Environ Med Date: 2015-07-06 Impact factor: 4.402
Authors: Cari M Kitahara; Dóra K Rmendiné Farkas; Jens Otto L Jørgensen; Deirdre Cronin-Fenton; Henrik Toft Sørensen Journal: J Clin Endocrinol Metab Date: 2018-06-01 Impact factor: 5.958
Authors: Cari L Meinhold; Elaine Ron; Sara J Schonfeld; Bruce H Alexander; D Michal Freedman; Martha S Linet; Amy Berrington de González Journal: Am J Epidemiol Date: 2009-11-30 Impact factor: 4.897
Authors: Sara E Murray; David F Schneider; Philip S Bauer; Rebecca S Sippel; Herbert Chen Journal: J Am Coll Surg Date: 2013-03-20 Impact factor: 6.113