According to the World Health Organization (WHO), about  15% of human cancers are caused by viruses
 The basic premises of this presentation are:
1. Cancer is a viral disease.
2. Tumor evolution is a response to viral infection.
3. All tumors evolve in the same way.
4. Neoplasia is a process shaped
 by   two components (sub-processes)
4a. A driving virus
4b. The response by the organism.
5. Cancer progresses as a cancer field
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