How did cancer come about?

This should answer your question:

http://www.cancer.org/docroot/CRI/content/CRI_2_6x_the_history_of_cancer_72.asp

Part of this website says:

Oldest Descriptions of Cancer

Cancer has afflicted humans throughout recorded history. It is no surprise that from the dawn of history doctors have written about cancer. Some of the earliest evidence of cancer is found among fossilized bone tumors, human mummies in ancient Egypt, and ancient manuscripts.

Bone remains of mummies have revealed growths suggestive of the bone cancer, osteosarcoma. In other cases, bony skull destruction as seen in cancer of the head and neck has been found.

Our oldest description of cancer (although the term cancer was not used) was discovered in Egypt and dates back to approximately 1600 B.C.

The Edwin Smith Papyrus, or writing, describes 8 cases of tumors or ulcers of the breast that were treated by cauterization, with a tool called “the fire drill.” The writing says about the disease, “There is no treatment.”

Origin of the Word Cancer

The origin of the word cancer is credited to the Greek physician Hippocrates (460-370 B.C.), considered the “Father of Medicine.” Hippocrates used the terms carcinos and carcinoma to describe non-ulcer forming and ulcer-forming tumors.

In Greek these words refer to a crab, most likely applied to the disease because the finger-like spreading projections from a cancer called to mind the shape of a crab. Carcinoma is the most common type of cancer.