Take a look at Siddhartha Mukherjee extraordinary book "The Emperor of all Maladies", which is subtitled "A Biography of Cancer". This is mainly a modern history of the disease concentrating on the science and the personal stories of the "War on Cancer", but an early chapter does discuss historic accounts of the disease and its treatment at least as far back as a couple thousand years ago in Egypt, among other places.

There are multi-thousand year-old skeletal remains that contain osteosarcoma (malignant bone tumors), but the relative scarcity of such specimens is evidence that, until the modern erase, cancer was a relatively rare affliction. We have come to learn that it is actually a disease that takes time to manifest in most cases (aside from certain childhood types). Basically we see so much of it today simply because we are living so much longer, as we have reduced mortality from most other causes.