A couple of ideas that don't require complete refinishing;
1- Remove knobs, clean the door, lightly sand affected area with 180 grit sandpaper and apply Watco or Howard's Restor-A-Finish (wiping with clean rag). You will need to choose a similar color.
This might work. Depends on how dark your cabinets are now and how worn. Worth trying.
2- If your cabinet finish is worn and not the stain then lightly sand to remove the worn finish but not remove the stain. A new finish will need applying. I recommend a good spar varnish. This would have to be done to the entire door.
I would try using Watco or Howard's first. These products can be applied to the entire door surface to spruce up an existing finish.