Secondary cancer-incidence risk estimates for external radiotherapy and high-dose-rate brachytherapy in cervical cancer: phantom study.
This study was designed to estimate radiation-induced secondary cancer risks from high-dose-rate (HDR) brachytherapy and external radiotherapy for patients with cervical cancer based on measurements of doses absorbed by various organs. Organ doses from HDR brachytherapy and external radiotherapy were measured using glass rod dosimeters. Doses to out-of-field organs were measured at various loca-tions inside an anthropomorphic phantom. Brachytherapy-associated organ doses were measured using a specialized phantom that enabled applicator insertion, with the pelvis portion of the existing anthropomorphic phantom replaced by this new phantom. Measured organ doses were used to calculate secondary cancer risk based on Biological Effects of Ionizing Radiation (BEIR) VII models. In both treatment modalities, organ doses per prescribed dose (PD) mostly depended on the distance between organs. The locations showing the highest and lowest doses were the right kidney (external radiotherapy: 215.2 mGy; brachytherapy: 655.17 mGy) and the brain (external radiotherapy: 15.82 mGy; brachytherapy: 2.49 mGy), respectively. Organ doses to nearby regions were higher for brachytherapy than for external beam therapy, whereas organ doses to distant regions were higher for external beam therapy. Organ doses to distant treatment regions in external radiotherapy were due primarily to out-of-field radiation resulting from scattering and leakage in the gantry head. For brachytherapy, the highest estimated lifetime attributable risk per 100,000 population was to the stomach (88.6), whereas the lowest risks were to the brain (0.4) and eye (0.4); for external radiotherapy, the highest and lowest risks were to the thyroid (305.1) and brain (2.4). These results may help provide a database on the impact of radiotherapy-induced secondary cancer incidence dur-ing cervical cancer treatment, as well as suggest further research on strategies to counteract the risks of radiotherapy-associated secondary malignancies.
Korea University; Samsung Medical Center. 123@123.com.
Boram
B
Lee
Sung Hwan
SH
Ahn
Hyeyoung
H
Kim
Jaeman
J
Son
Jiwon
J
Sung
Youngyih
Y
Han
Seung Jae
SJ
Huh
Jin Sung
JS
Kim
Dong Wook
DW
Kim
Myonggeun
M
Yoon
D001918:Brachytherapy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D009010:Monte Carlo Method; D009381:Neoplasms, Radiation-Induced / Q000000981:diagnostic imaging / Q000453:epidemiology*; D016609:Neoplasms, Second Primary / Q000000981:diagnostic imaging / Q000453:epidemiology*; D058958:Organs at Risk / Q000528:radiation effects*; D019047:Phantoms, Imaging; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D018570:Risk Assessment; D002583:Uterine Cervical Neoplasms / Q000532:radiotherapy*
Ann ICRP. 2007;37(2-4):1-332
18082557
Radiat Prot Dosimetry. 2012 Jan;148(1):58-64
21335329
Phys Med. 2013 Nov;29(6):650-5
22921884
Front Oncol. 2015 Nov 26;5:261
26636040
Int J Radiat Oncol Biol Phys. 2003 May 1;56(1):83-8
12694826
Br J Radiol. 2009 Jan;82(973):35-40
18852212
Int J Gynecol Cancer. 2014 Feb;24(2):346-51
24407583
J Breast Cancer. 2015 Dec;18(4):378-85
26770245
World J Surg. 2016 Apr;40(4):895-905
26711638
Int J Radiat Oncol Biol Phys. 1991 Jan;20(1):87-93
1993634
Med Phys. 2008 Dec;35(12):5558-64
19175113
Int J Radiat Oncol Biol Phys. 2005 Jul 15;62(4):1204-16
15990026
Lancet Oncol. 2011 Apr;12(4):353-60
21454129
Int J Radiat Oncol Biol Phys. 2004 Nov 15;60(4):1144-53
15519786
Cancer. 1983 Mar 1;51(5):959-67
6821861
Int J Radiat Oncol Biol Phys. 1999 Mar 1;43(4):763-75
10098431
Med Phys. 2012 Oct;39(10 ):5814-24
23039620
J Radiol Prot. 2014 Jun;34(2):325-31
24705154
Int J Gynecol Cancer. 2007 Jul-Aug;17(4):833-42
17367320
Cancer. 1990 Dec 15;66(12):2451-6
2249184
Appl Radiat Isot. 2012 Aug;70(8):1616-23
22738837
Cancer. 2000 Jan 15;88(2):398-406
10640974
Radiat Prot Dosimetry. 2006;119(1-4):327-31
16709718
Phys Med Biol. 2012 Oct 7;57(19):6047-61
22968191
J Contemp Brachytherapy. 2013 Dec;5(4):250-7
24474977
Int J Radiat Oncol Biol Phys. 1991 Apr;20(4):667-76
2004942
Radiother Oncol. 2012 Oct;105(1):122-6
21993405
Radiat Res. 2002 Aug;158(2):220-35
12105993
Medicine (Baltimore). 2015 Oct;94(43):e1803
26512575