The problem is that, if I'm this doc, and I get your CT scan today and you've got a two centimeter mass in your liver, and you come back to me in three months and it's three centimeters, did that drug help you or not?
问题是，如果我就是这个医生，今天我拿到你的CAT扫描， 你的肝脏有个2厘米的东西， 3个月后你回来找我，那个东西3厘米了， 那么那个药物对你是否有帮助？