I have a 46 inch Samsung that has developed vertical lines on the left half of the screen. However, it does not go all the way to the left edge (see attached pic). The lines appear in front of the menu on all inputs.
After researching, it looks like it could be the TCON board, but I'm not sure. Hopefully it is not the panel itself.
What is the model of your TV. I had one line on my LN46A750. The part would have been over $900 to replace, but they no longer make the board for it. I was lucky and had an extended warranty through Geek Squad at BB. I got a $1200 credit towards new TV. Look up your TV on Samsungs parts site and see what the cost is.