"Trust but verify": There are standards for tumor measurement. However, for something with major life-altering consequences, having the same radiologist compare scans is important to avoid observational variability.

A neurologist I know, she always checks the actual scans as opposed to relying on the report narrative alone. Her background is in computer science, before her MD.

The issue with new analysis tools is that most doctors won't stake their reputation by exclusion. If a doctor says the tumor isn't growing, and it is, they are liable. If a neurosurgeon removes a benign tumor, then its business as usual.