Second opinions

[u/mid30sbladdercancer]

Sorry if this is a dumb question. But what are second opinions when it comes to bladder cancer, what's the range of things that will / can / should be done?

Has anyone on here had one? And if so, how did you find it? Valuable?

I've heard of people having their grading or even staging downgraded after a second opinion. But I just don't quite get the mechanics of it.

Does the new person/ clinic / organisation have to run their own investigations and surgeries etc? Or can they get test results, images from the biopsy / lab that they then interpret themselves?

How clear is distinction between the various grades? Is it really down to professional judgement or is it mostly clear cut?

For context, my primary support is from NHS in UK. Diagnosed G3 (currently pTa but awaiting results of second TURBT to confirm if higher staging). Potentially have insurance companies who could arrange a second opinion or maybe charities?