Taylor G N, Shabestari L, Williams J, Mays C W, Angus W, McFarland S
Cancer Res. 1976 Aug;36(8):2740-3.
The incidence rate of mammary neoplasia in a large colony of beagles and the relationship to internal skeletal and/or liver radiation, age, relatively late ovariectomy (4 years and older), endometritis, parity status, and adrenal weight were examined. Of these various factors, age was the only condition that was clearly correlated with changes in the mammary tumor incidence. The rate became significant at approximately eight years of age and increased progressively throughout the older age classes. Among the female dogs, the incidence of mammary cancer was higher than that of any other form of spontaneous malignancy.
研究了一个大型比格犬群体中乳腺肿瘤的发病率，以及与内骨骼和/或肝脏辐射、年龄、相对较晚的卵巢切除术（4岁及以上）、子宫内膜炎、产次状况和肾上腺重量的关系。在这些各种因素中，年龄是唯一与乳腺肿瘤发病率变化明显相关的条件。该发病率在大约8岁时变得显著，并在老年组中逐渐增加。在雌性犬中，乳腺癌的发病率高于任何其他形式的自发恶性肿瘤。
