TY - JOUR
T1 - A pooled analysis of thyroid cancer incidence following radiotherapy for childhood cancer
AU - Veiga, Lene H.S.
AU - Lubin, Jay H.
AU - Anderson, Harald
AU - De Vathaire, Florent
AU - Tucker, Margaret
AU - Bhatti, Parveen
AU - Schneider, Arthur
AU - Johansson, Robert
AU - Inskip, Peter
AU - Kleinerman, Ruth
AU - Shore, Roy
AU - Pottern, Linda
AU - Holmberg, Erik
AU - Hawkins, Michael M.
AU - Adams, M. Jacob
AU - Sadetzki, Siegal
AU - Lundell, Marie
AU - Sakata, Ritsu
AU - Damber, Lena
AU - Neta, Gila
AU - Ron, Elaine
PY - 2012/10/1
Y1 - 2012/10/1
N2 - Childhood cancer five-year survival now exceeds 7080. Childhood exposure to radiation is a known thyroid carcinogen; however, data are limited for the evaluation of radiation dose-response at high doses, modifiers of the dose-response relationship and joint effects of radiotherapy and chemotherapy. To address these issues, we pooled two cohort and two nested case-control studies of childhood cancer survivors including 16,757 patients, with 187 developing primary thyroid cancer. Relative risks (RR) with 95 confidence intervals (CI) for thyroid cancer by treatment with alkylating agents, anthracyclines or bleomycin were 3.25 (0.914.9), 4.5 (1.417.8) and 3.2 (0.810.4), respectively, in patients without radiotherapy, and declined with greater radiation dose (RR trends, P 0.02, 0.12 and 0.01, respectively). Radiation dose-related RRs increased approximately linearly for <10 Gy, leveled off at 1015-fold for 1030 Gy and then declined, but remained elevated for doses >50 Gy. The fitted RR at 10 Gy was 13.7 (95 CI: 8.024.0). Dose-related excess RRs increased with decreasing age at exposure (P < 0.01), but did not vary with attained age or time-since-exposure, remaining elevated 25 years after exposure. Gender and number of treatments did not modify radiation effects. Thyroid cancer risks remained elevated many decades following radiotherapy, highlighting the need for continued follow up of childhood cancer survivors.
AB - Childhood cancer five-year survival now exceeds 7080. Childhood exposure to radiation is a known thyroid carcinogen; however, data are limited for the evaluation of radiation dose-response at high doses, modifiers of the dose-response relationship and joint effects of radiotherapy and chemotherapy. To address these issues, we pooled two cohort and two nested case-control studies of childhood cancer survivors including 16,757 patients, with 187 developing primary thyroid cancer. Relative risks (RR) with 95 confidence intervals (CI) for thyroid cancer by treatment with alkylating agents, anthracyclines or bleomycin were 3.25 (0.914.9), 4.5 (1.417.8) and 3.2 (0.810.4), respectively, in patients without radiotherapy, and declined with greater radiation dose (RR trends, P 0.02, 0.12 and 0.01, respectively). Radiation dose-related RRs increased approximately linearly for <10 Gy, leveled off at 1015-fold for 1030 Gy and then declined, but remained elevated for doses >50 Gy. The fitted RR at 10 Gy was 13.7 (95 CI: 8.024.0). Dose-related excess RRs increased with decreasing age at exposure (P < 0.01), but did not vary with attained age or time-since-exposure, remaining elevated 25 years after exposure. Gender and number of treatments did not modify radiation effects. Thyroid cancer risks remained elevated many decades following radiotherapy, highlighting the need for continued follow up of childhood cancer survivors.
UR - http://www.scopus.com/inward/record.url?scp=84867080213&partnerID=8YFLogxK
U2 - 10.1667/RR2889.1
DO - 10.1667/RR2889.1
M3 - Article
C2 - 22857014
AN - SCOPUS:84867080213
SN - 0033-7587
VL - 178
SP - 365
EP - 376
JO - Radiation Research
JF - Radiation Research
IS - 4
ER -