Clipped wings
Their 'standard' policy was the same for my very low grade non-hodgkins lymphoma, diagnosed in 2007, but I ended up getting an unrestricted Class 2 and restricted Class 1 back, just six months after my radiotherapy finished.
SAS is right...ask your oncologist to write, covering all the points in their standard letter and talk to them directly. I found them to be very helpful and understanding and prepared to consider each case on its own merits. Your oncologist might also have access to better and more recent clinical data in regards to recurrence rates.
PM me if you'd like to chat about it, I'm only a few miles away...