This term generally includes all cancer sites from below the brain down to the low neck (go here). Many of these cancers are caused by smoking or alcohol, though there has been an increase in cancers thought to be caused by the HPV virus (go here) and in some sites (e.g. parotid) there is no obvious cause. Most of these cancers are squamous cell carcinomas. For the role of diet go here.

The best sites for general information include those from the ACS (here and here), the booklets from the NCI (here and here) and the main NCI sites (here, here, here, and here ) the ASCO site (here) and the NCCN (here).

Other sections include anatomy, understanding and treatment of specific sites, combining  chemotherapy with radiation, side effects of radiation and other miscellaneous topics.