Benign Tumors of Vallecula and Root of Tongue (Hypopharynx)
In the vallecula and root of the tongue, small connective tissue tumors of benign character may exist for a long time before they become large enough to cause solid-food dysphagia. Occasionally, the presenting complaint may be difficulty in breathing when the head is in certain postures; the primary reason for this is that these benign tumors are frequently pedunculated and compromise the airway when the tumor mass is dislodged by a change in position of the head. The tumors are smooth, soft, and covered by an intact mucosa. The most common of them is the retention cyst of the epiglottis, which is easily detected during a mirror examination. The cyst may be freely movable because of the pedunculated attachment to the mucosal surface of the epiglottis. Removal by forceps under indirect laryngoscopy is adequate.
A fibrolipoma of the vallecula may not be discovered until there is interference with normal breathing. The tumor mass is usually rounded, of a yellowish tinge, and covered by a smooth mucosa. The mass has a sessile attachment to the lingual surface of the epiglottis, which it displaces posteriorly, thereby overhanging the aditus of the larynx. The benign nature of the tumor is usually self-evident. Treatment is surgical excision of the lesion.
Neuroma of the vallecula (not illustrated) is rare but may attain a large size before becoming apparent. The symptoms vary with the size of the tumor and may result in dysphagia or difficulty in breathing.
An aberrant lingual thyroid gland may be present for a long time before it is diagnosed. It makes its appearance as a smooth bulge in the posterior surface of the tongue, starting in the region of the foramen cecum and extending posteriorly to the lingual surface of the epiglottis. The mass presents as a smooth surface soft to the touch and covered by an intact mucosa. Some tumors may become so large that they interfere with respiration; tumor extension inferiorly and/or depression of the epiglottis into the laryngeal vestibule may be the reason. The diagnosis should always be entertained when a smooth tumor of the base of the tongue is encountered. The diagnosis is often made by exclusion. A thyroid scan with a radioactive iodine tracer demonstrated in the region of the mass will establish the diagnosis. Biopsy typically yields insufficient tissue because of the depth required to reach the aberrant thyroid tissue. If the mass produces no symptoms, therapy is probably not indicated.
Microscopically, the aberrant lingual thyroid typically presents as a normally functioning thyroid gland, which should be left intact whenever possible. A thyroid scan will demonstrate the functional nature of the lingual gland, If the mass is so big that it endangers respiration, therapeutic doses of radioactive iodine suffice to cause a subsidence of the tumor and to create a hypothyroid state, which must be treated accordingly. Adenomatous tissue, which can be found in the lingual thyroid gland and is also often found in the normally located thyroid, is best removed by surgical resection. In the base of the tongue, other tumor masses may occur that require removal. Myoblastoma is a common finding and responds to surgical extirpation. Amyloid tumors of the tongue and chondromas have been described and are less amenable to therapy.