If you know someone who has cancer, please get the book, "The China Study". I got a copy from my local library (had to reserve it).
It is written by a researcher who spent years researching the role of protein in cancer. Anyway, to sum up the book: eating animal protein (meat, fish, eggs, dairy) allows cancer to develop and grow. While, getting your protein from plant sources does not promote cancer growth and the cancer growth can be stopped or started based on the amount and source of your protein consumption. Several different studies have confirmed this finding. It's one of those cases where the government hasn't spread the word about it.
Please take a look at this book. It's really quite fascinating and informative. I wish I had this book back when my mom was diagnosed with breast cancer.