NAVLE（北美执业兽医考题）Day 781

Q1:A 10-year old female spayed Siamese cat presents for a new lump the owner found a month ago. She was spayed last year before she was adopted from the shelter. The owner states that the lump has grown over the last month, and it doesnt seem to bother the cat. On exam, the 2 cm lump is located on the left 2nd mammary gland, and no other lumps are noted. The lump is freely moveable, and chest radiographs are clear. What is the chance that this tumor is malignant?一只10岁已绝育暹罗猫由于主人在1个月前新发现的肿块前来就诊。这只猫在一年前被领养之前做了绝育。主诉这个肿块在过去的一个月有慢慢变大的趋势，但没有对这只猫造成影响。体格检查提示这只猫左侧第二乳腺有一个2cm左右大小的肿块，其它位置没有发现异常。肿块为游离性的，其胸腔X光片正常。这个肿块为恶性的概率是多少？