Laryngeal cancer. Light micrograph of a section through laryngeal tissue showing cancerous cells that have formed small lobules (round). This is a carcinoma, a malignant (cancerous) tumour that arises from the lining (epithelium) of the larynx. The larynx is situated at the top of the trachea (windpipe) and houses the voice box. The most common form of laryngeal cancer is squamous cell carcinoma. The two most important risk factors for this cancer are smoking and heavy alcohol consumption. The majority of cases are found in men over 60. Treatment is with radiation therapy or laser excision of the tumour.