Hello,
I realise this question is 2 years old by now and unlikely to help Rowan but I have experienced the same problem when importing immunofluorescence pictures for my PhD thesis. I thought that word might be changing my .tif somehow when I imported it so I tried copying it from word back into photoshop and I noticed that the colors were darker than my original .tif file that I had generated using adobe Illustrator. Turns out I was exporting from illustrator using CMYK color model instead of RGB, I believe word uses RGB. I tried exporting and importing to word again using RGB (also ticked a little box that said 'imbed ICC profile') and printed it. To my eye the color problem seems to be fixed. Hope this helps someone