Benjamin S A, Lee A C, Angleton G M, Saunders W J, Keefe T J, Mallinckrodt C H
Collaborative Radiological Health Laboratory, Colorado State University, Fort Collins 80523, USA.
Radiat Res. 1998 Sep;150(3):330-48.
To evaluate the lifetime carcinogenic hazards of exposure to ionizing radiation during development, 1,680 beagles received whole-body exposures to 60Co gamma rays or sham exposures. Eight groups of 120 dogs each received mean doses of 15.6-17.5 or 80.8-88.3 cGy in early, mid- or late gestation, at 8, 28 or 55 days postcoitus or at 2 days after birth. Another group of 120 dogs received a mean dose of 82.6 cGy as 70-day-old juveniles and one group of 240 dogs received a mean dose of 81.2 cGy as 365-day-old young adults. Sham irradiations were given to 360 controls. Sexes were equally represented. In 1,343 dogs allowed to live out their life span, neoplasia was a major disease, contributing to mortality in 40% of the dogs. There was a significant increase in benign and malignant neoplasms occurring in young dogs (<4 years old), including fatal malignancies, after irradiation in the perinatal (late fetal and neonatal) periods. The lifetime incidence of fatal neoplasms was also increased in dogs irradiated perinatally. Three malignancies-lymphomas, hemangiosarcomas and mammary carcinomas-accounted for 51% of all fatal tumors. There was an apparent lifetime increase and earlier onset of lymphomas in dogs exposed as fetuses. Fatal hemangiosarcomas were increased in dogs irradiated early and late in gestation. Fatal mammary carcinomas were not increased by irradiation, although non-fatal carcinomas were increased after perinatal exposure. Myeloproliferative disorders and central nervous system astrocytomas appeared to be increased in perinatally irradiated dogs. These data suggest that irradiation in both the fetal and neonatal periods is associated with increased early onset and lifetime cancer risk.
为评估发育过程中暴露于电离辐射的终生致癌风险，1680只比格犬接受了全身60Coγ射线照射或假照射。八组，每组120只狗，分别在妊娠早期、中期或晚期，交配后8、28或55天或出生后2天接受平均剂量为15.6 - 17.5或80.8 - 88.3 cGy的照射。另一组120只狗在70日龄幼犬时接受平均剂量为82.6 cGy的照射，一组240只狗在365日龄青年犬时接受平均剂量为81.2 cGy的照射。对360只对照犬进行假照射。雌雄比例相同。在1343只存活至寿命终期的狗中，肿瘤是主要疾病，导致40%的狗死亡。围产期（胎儿晚期和新生儿期）照射后，幼犬（<4岁）出现的良性和恶性肿瘤显著增加，包括致命性恶性肿瘤。围产期照射的狗中，致命肿瘤的终生发病率也有所增加。三种恶性肿瘤——淋巴瘤、血管肉瘤和乳腺癌——占所有致命肿瘤的51%。在胎儿期暴露的狗中，淋巴瘤的终生发病率明显增加且发病时间提前。妊娠早期和晚期照射的狗中，致命性血管肉瘤增加。虽然围产期暴露后非致命性乳腺癌增加，但照射并未使致命性乳腺癌增加。围产期照射的狗中，骨髓增殖性疾病和中枢神经系统星形细胞瘤似乎有所增加。这些数据表明，胎儿期和新生儿期的照射均与癌症发病提前和终生癌症风险增加有关。
