I used all of the same squares as I did for the Alzheimer's blanket, but used just one shade of purple (a brighter purple than the Alzheimer's square). Her cancer colors are also purple and white... so that was a lot of purple!
I joined the squares with the continous join as you go method, linked to before... and did a similar but different edging. I used the same bright purple I used in all the squares for the joining and the border. You can barely see the joining, can you?