How do you guys handle patients going for 2nd opinion behind your back?

[Dr.Brian]

In fairness to the non physicians who posted, they gave you their valid opinions on the topic.
They agreed that 2nd opinions are important, especially when the stakes are high.
They don't feel obligated to tell you that they are seeking other opinions.
They're appropriately concerned about a physician who feels threatened by that.
When I was at Stanford, there was a senior neurosurgeon there who would successfully do "hail mary" resections that others would not touch. I would often hear the stories of his patients being refused surgery elsewhere, sometimes multiple places, before getting a referral to this surgeon. My sister in law's rare cancer was misdiagnosed by an accomplished world expert at Johns Hopkins. People make mistakes, interpret things differently, and there is often more than one accepted treatment plan. Second opinions can be lifesaving, empowering, and should be encouraged.