Benjamin S A, Stephens L C, Hamilton B F, Saunders W J, Lee A C, Angleton G M, Mallinckrodt C H
Collaborative Radiological Health Laboratory, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, USA.
Vet Pathol. 1996 Sep;33(5):486-94. doi: 10.1177/030098589603300502.
The thyroids were evaluated in 276 control Beagles that were allowed to live out their full life span (mean = 12 years) in a closed breeding colony. Lymphocytic thyroiditis was found in 26.3% of the dogs. This lesion was characterized by lymphoplasmacytic inflammation accompanied by follicular destruction. The thyroiditis was progressive, resulting in severe atrophy of follicular tissue, and 44 dogs (15.9%) were diagnosed as hypothyroid at the time of death. In accordance with the experimental protocol, hypothyroid dogs were not given thyroxine replacement therapy. There was a high degree of heritability for the hypothyroidism. Hypothyroid dogs had an increased risk for thyroid follicular epithelial neoplasia and, in particular, for follicular adenocarcinomas. Twenty-four of the 44 hypothyroid dogs (54.5%) had one or more follicular thyroid neoplasms, whereas only 53 of the 232 (22.8%) clinically euthyroid dogs had similar tumors. Multiple thyroid tumors were present in 14 of the 44 (31.8%) hypothyroid dogs but in only 12 of the 232 (5.2%) euthyroid dogs. One or more follicular adenocarcinomas were present in 15 of the 44 (34.1%) hypothyroid dogs but in only 16 of the 232 (6.9%) euthyroid dogs. There was no difference in prevalence of hypothyroidism or tumors between the sexes. The strong association between progressive lymphocytic thyroiditis, hypothyroidism, and thyroid follicular neoplasia in these Beagles probably relates to promotion of residual follicular epithelium by chronic excess thyrotropin stimulation.
在一个封闭的繁殖群体中，对276只对照比格犬的甲状腺进行了评估，这些比格犬被允许活到其自然寿命（平均12岁）。在26.3%的犬中发现了淋巴细胞性甲状腺炎。该病变的特征是淋巴细胞浆细胞性炎症伴有滤泡破坏。甲状腺炎呈进行性发展，导致滤泡组织严重萎缩，44只犬（15.9%）在死亡时被诊断为甲状腺功能减退。根据实验方案，甲状腺功能减退的犬未接受甲状腺素替代治疗。甲状腺功能减退具有高度遗传性。甲状腺功能减退的犬患甲状腺滤泡上皮肿瘤的风险增加，尤其是滤泡腺癌。44只甲状腺功能减退的犬中有24只（54.5%）有一个或多个甲状腺滤泡肿瘤，而232只临床甲状腺功能正常的犬中只有53只（22.8%）有类似肿瘤。44只甲状腺功能减退的犬中有14只（31.8%）有多个甲状腺肿瘤，而232只甲状腺功能正常的犬中只有12只（5.2%）有多个甲状腺肿瘤。44只甲状腺功能减退的犬中有15只（34.1%）有一个或多个滤泡腺癌，而232只甲状腺功能正常的犬中只有16只（6.9%）有滤泡腺癌。甲状腺功能减退或肿瘤的患病率在性别之间没有差异。这些比格犬中进行性淋巴细胞性甲状腺炎、甲状腺功能减退和甲状腺滤泡肿瘤之间的密切关联可能与慢性促甲状腺素刺激对残余滤泡上皮的促进作用有关。
