Pink line of pixels across screen

Hello, everyone.

Yesterday I was using my main computer which is the iMac 27" Late 2013. I went to eat something and when I came back, a verticle purple line was across my display. (Side note: I was using Windows 10 at the time via Boot Camp for a program called VTFEdit).

I put several colors on my display, and it seems that if the display is all blue/all red the line dissapeares, but when there are multiple colors, all green or all white, the line shows up. The line also turns green when booting the computer, but surprisingly it dissappears if the system is booted and I have a fullscreen black image.

I am aware this is a hardware issue, and I believe the pixels are stuck. As the computer is no longer in warranty, is there anything I can do at home to fix it, or do I have to bring it to an Apple Store and pay an extra fee? Also, before taking it into an Apple Store, do I have to back up my computer?

Thank you and best wishes.