Have yellowish brown discoloration around screen

Have yellowish brown discoloration around screen that remains constant, getting larger. More noticable on B&W shows and light colors are shown. Had someone come out to check and said it was the LCD drive unit. The service contract company will not honor the agreement anymore. So, would like to know if that is really the part I need, the LCD drive unit or is it something else before I buy the part. Panasonic PT-50LC14
Part is - LSEP3126A