Please help - Is there truly a cure for people with high Ki-67 levels?

I am hoping someone can give me hope that my wonderful husband will be truly cured. He has Diffuse Large B-Cell Lymphoma, stage 2. His IPI is 1. He is 61 and is tolerating RCHOP well. We have one final treatment to go, just a week before Christmas.

Our doctor says my husband has a good chance of a cure. A lifetime cure. But I am a scientist, and one of my job aspects is to research medical articles and come to valid conclusions.

My husband's Ki-67 index was 95%. This is an indication of how rapidly the cancer cells are reproducing, and 95% is nearly as high as you can get. The research I've read states that 'complete response' rates (cure) immediately following treatment are the same in people with both high and low Ki-67 rates. BUT, relapse rates two years post treatment are much higher in those with high Ki-67 levels. AND, event-free survival is much lower in those with high Ki-67 levels two years post-treatment.

I am terrified that we will have gone through so much, only to face the demon again, soon and with much less success. Is there anyone who can give me hope, who has or knows someone who has a high Ki-67 and has gone through treatement with long term survival? Can there be a genuine cure for those who have high Ki-67 levels? Does anyone have experience in this? Your advice and wisdom is much needed. Thank you!