You might not rule a kingdom, or have the veto power of the president, but people will respond to your every beck and call. What you tell them could be a matter of life or death, so it's generally important that, when you're at work, the people around you listen to what you have to say.
You aren't just reporting news; you're telling cancer patients that you'll need to subject them to radiation therapy, and you're telling them that it doesn't always work. These aren't easy conversations.
Then again, you might get to tell a patient the happy news that the radiation has worked and they're cancer-free. Either way, you carry a pretty powerful knowledge base, and people will take note when you put it to good use.