What is the nasopharynx ?The nasopharynx is made up of the upper part of the pharynx (throat) behind the nose. The pharynx is a hollow tube that begins behind the nose and ends at the top of the trachea (windpipe) and esophagus (tube that goes from the throat to the stomach). The nostrils lead into the nasopharynx, while an opening on each side of the nasopharynx leads into each ear via the Eustachian tubes. What is nasopharyngeal cancer ?Nasopharyngeal cancer occurs when malignant (cancerous) cells form in the tissues of the nasopharynx. Cancer is the uncontrollable growth of cells that invade and cause damage to surrounding tissue. In most cases, nasopharyngeal cancer begins in the thin, flat cells (squamous cells) that line the oropharynx (the part of the throat behind the mouth).