The difference is going to a national cancer center.

My late wife was treated for metastatic melanoma at MSK. Their approach is to have clinical teams and a tumor board that are assigned patients with related cancers. They are seeing many patients and there’s a warm hand off between specialists. Your radiation oncologist, medical oncologist and surgery / neuro specialists are on a team and know each other and are often familiar with the cases. In my wife’s case the community oncologist was wonderful, but he was a sole practitioner for this particular cancer.

In the second opinion scenario, they get to use that experience and caseload to look at a case with some perspective. Your community oncologist likely works on a small team and may not have the luxury of time and exposure to trials, etc.

Think of it as a second set of eyes.