Hello, 

my dad had the same operation about 6 years ago now. He found that he couldn't able drink a lot of alcohol anymore & that his food intake is more limited (he cannot eat as much, although he eats more now than after his operation, and also finds it hard to tolerate spicy foods). Sometimes he experiences a burning pain which the doctors have been unable to explain but presumably is relative to scar tissue. I would suggest drinking perhaps smoothies and soft foods to begin with after the operation. Other than these issues my dad seems to be back to a somewhat normal life although he finds it difficult to regain the weight he lost during chemo. I hope this helps you a little, apologies that it is from a second hand account. I wish your mum all the best 

Thanks so much for reply - that all sounds very positive!  My worry is that she will go through a terrible time and not benefit from it but knowing your dad is 6 years post op gives me hope! 
Happy New Year

It is of course a large operation but much better than the alternative. 
happy new year to you too :)