||The more common carcinomas of the head and neck in etiology, histopathology, clinical presentation, and therapy. Incidence and epidemiology the number of new cases of head and neck cancers in the united states was 38,530 in 2004, accounting for about 3% of adult malignancies. The worldwide incidence exceeds half a million cases annually. In north america and europe, the tumors usually arise from the oral cavity, oropharynx, or larynx, whereas nasopharyngeal cancer is more common in the mediterranean countries and in the far east. Etiology and genetics alcohol and tobacco use are the most common risk factors for head and neck cancer in the united states. Smokeless tobacco is an etiologic agent for oral cancers. Other potential carcinogens include marijuana and occupational exposures such as nickel refining, exposure to textile fibers, and woodworking. Head and neck cancer news barrow researchers make breakthrough… people with allergies may have… genetic markers hope for new brain… cancer in the elderly: research… researchers discover non-surgical… researchers link dental x-rays… dental x-rays may raise risk of… head and neck cancer news » dietary factors may contribute. The incidence of head and neck cancer is highest in people with the lowest consumption of fruits and vegetables. Certain vitamins, including dietary carotenoids, may be protective; retinoids are being tested for prevention. Some head and neck cancers may have a viral etiology. The dna of human papillomavirus has been detected in the tissue of oral and tonsil cancers, and may predispose to oral cancer in the absence of tobacco and alcohol use. Epstein-barr virus (ebv) infection is associated with nasopharyngeal cancer. Nasopharyngeal cancer occurs endemically in some countries of the mediterranean and far east, where ebv antibody titers can be measured to screen high-risk populations. Nasopharyngeal cancer has also been associated with consumption of salted fish. buy cheap viagra http://medicaresupplementspecialists.com/pfz-viagra-prescriptions-mn/ cheap generic viagra cheap generic viagra buy cheap viagra viagra online buy viagra online buy viagra viagra online generic viagra online No specific risk factors or environmental carcinogens have been identified for salivary gland tumors. Next article hostopathology, carcinogenesis, and molecular biology » » squamous cell carcinoma of the upper aerodigestive tract the term head and neck cancer, if strictly applied, encompasses all cancers involving the head and neck region, including those involving the skin, brain, eyes, upper aerodigestive system, salivary glands, thyroid, and so forth. In actuality, this term is used to describe cancers arising from the mucosa of the upper aerodigestive tract, and for the purposes of this section it is these tumors that will be highlighted. The involved mucosa is that of the nose, paranasal sinuses, oral cavity, nasopharynx, oropharynx, hypopharynx, larynx, and cervical esophagus. While many histologic types of cancer may occ.