It's obvious alcohol and tobacco users greatly increase their risk for developing this cancer, what about those who don't abuse these substances? what do they need to be aware of to prevent this?

Need more info: I don't know what cancer you are talking about. Alcohol and tobacco can increase the risks of lots of cancers.

Which cancer??: Smoking is highly associated with lung cancer, head and neck (mouth, tongue, lips, throat) and esophageal cancers, stomach cancer, bladder cancer and breast cancer. Heavy alcohol use vastly increases chances of head and neck cancer, as well as breast, bladder, stomach and colon cancer. However, many other risk factors can be present - environmental&workplace exposure, hereditary risks, the sun etc.