Warner M R
J Natl Cancer Inst. 1976 Jul;57(1):57-61. doi: 10.1093/jnci/57.1.57.
The age incidence and site distribution of 2,142 mammary dysplasias were documented for 39 beagle bitches 6 months to 4 years of age. Lesion onset was at 2-3 years of age, at which time more than 50% of the females had dysplasias. Dysplasias appeared before palpable tumors. Posterior mammae developed more lesions than did anterior mammae. Thus the gradient for early onset of lesions coincided with the gradient for tumor frequency reported previously; a preneoplastic potential is suggested for (some) dysplasias. Problems of defining normal tissue are discussed.
记录了39只6个月至4岁的比格犬母犬发生的2142例乳腺发育异常的年龄发病率和部位分布。病变开始于2至3岁，此时超过50%的雌性犬出现发育异常。发育异常出现在可触及肿瘤之前。后乳腺比前乳腺发生的病变更多。因此，病变早期发生的梯度与先前报道的肿瘤发生频率梯度一致；提示（某些）发育异常具有肿瘤前期潜能。讨论了定义正常组织的问题。
