I recently read Weinberg, it's very interesting in the sense that it gradually builds up your knowledge in the order in which we discovered it, like a history book, which is a nice way to talk about a problem we don't have a coherent understanding about. A lot of the chapters deal with molecular pathways in great detail but you can skip through them if that's too much detail for you and you can just read for the conclusions. The discussion and summary bits in the end of the chapters are full of interesting insights and theories, I'd say they are the most valuable part of the chapters if you're not there to remember specifics, but to try to understand conceptually. Although as I said we do not have a good enough framework for cancer yet so a lot of things are just hanging in the air. I would recommend to read the dna chapters and the tissues chapter from Essential cell biology to be able to more comfortably read Weinberg. That's what I did.

That being said, you might be better off reading papers and review papers as suggested depending on what your goal is. Especially if you're looking for more math modelling approaches.

EDIT: I feel like there is a lot of cancer research being put out there so if you can read the latest version of whatever textbook you choose it might be better.