Quick Review for Patients
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The embryonic tongue is formed by two lateral processes (lingual tubercles) meeting in the midline and fusing above a central structure from the first and second branchial arches, the tuberculum impar. The posterior dorsal point of fusion is occasionally defective, leaving a rhomboid-shaped, smooth erythematous mucosa lacking in papillae or taste buds. This median rhomboid glossitis (central papillary atrophy, posterior lingual papillary atrophy) is a focal area of susceptibility to recurring or chronic atrophic candidiasis, prompting a recent movement toward the use of posterior midline atrophic candidiasis as a more appropriate diagnostic term.
The latter term has certain difficulties, however, because not all cases
improve with antifungal therapy or show initial evidence of fungal infection.
The erythematous clinical appearance, moreover, is due primarily to the absence
of filiform papillae, rather than to local inflammatory changes, as first
suggested in 1914 by Brocq and Pautrier. The lesion is found
in one of every 300-2,000 adults, depending on the rigor of the clinical
examinations (Table 1). It is seldom biopsied unless the red
discoloration is confused with precancerous erythroplakia or its
surface shows pronounced nodularity.
Median rhomboid glossitis presents in the posterior midline of the dorsum of the tongue, just anterior to the V-shaped grouping of the circumvalate papillae. The long axis of the rhomboid or oval area of red depapillation is in the anterior-posterior direction. Most cases are not diagnosed until the middle age of the affected patient, but the entity is, of course, present in childhood. There appears to be a 3:1 male predilection.
Those lesions with atrophic candidiasis are usually more erythematous but some respond with excess keratin production and, therefore, show a white surface change. Infected cases may also demonstrate a midline soft palate erythema in the area of routine contact with the underlying tongue involvement; this is euphemistically referred to as a kissing lesion.
Lesions are typically less than 2 cm. in greatest dimension and most demonstrate a smooth, flat surface, although it is not unusual for the surface to be lobulated. Occasional lesions have surface mamillations raised more than 5 mm. above the tongue surface, and occasional lesions are located somewhat anterior to the usual location. None have been reported posterior to the circumvallate papillae.
Prior to biopsy, the clinician should be certain that the midline lesion does not represent a lingual thyroid, as it may be the only thyroid tissue present in the patient's body. Additional clinical look-alike lesions include the gumma of tertiary syphilis, the granuloma of tuberculosis, deep fungal infections, and granular cell tumor.
Pathology and Differential Diagnosis
Median rhomboid glossitis shows a smooth or nodular surface covered by atrophic stratified squamous epithelium overlying a moderately fibrosed stroma with somewhat dilated capillaries. Fungiform and filiform papillae are not seen, although surface nodules may mimic or perhaps represent anlage of these structures. A mild to moderately intense chronic inflammatory cell infiltrate may be seen within subepithelial and deeper fibrovascular tissues.
Chronic candida infection may result in excess surface keratin or extreme
elongation of rete processes and premature keratin production with individual
cells or as epithelial pearls (dyskeratosis) deep in the processes.
Silver staining for fungus will often reveal candida hyphae and spores
in the superficial layers of the epithelium. This pseudoepitheliomatous
hyperplasia may be quite pronounced, and the tangential cutting of such
a specimen may result in the artifactual appearance of cut rete processes
as unconnected islands of squamous epithelium, leading to a mistaken diagnosis
of well differentiated squamous cell carcinoma. Because of this
difficulty, it is recommended that the patient be treated with topical
antifungals prior to biopsy of a suspected median rhomboid glossitis.
Treatment and Prognosis
No treatment is necessary for median
rhomboid glossitis, but nodular cases are often removed for microscopic
evaluation. Recurrence after removal is not expected, although
those cases with pseudoepitheliomatous hyperplasia should be followed closely
for at least a year after biopsy to be certain of the benign diagnosis.
Antifungal therapy (topical troches or systemic medication) will reduce clinical
erythema and inflammation due to candida infection. This therapy, as stated
earlier, should ideally be given prior to the biopsy, in order to reduce
the candida-induced pseudoepitheliomatous hyperplasia features. Some lesions
will disappear entirely with antifungal therapy.
References (Chronologic Order)
Note: For general references click on link to the left.
Brocq L, Pautrier LM. Glossite losangue mediane de la face dorsale de la langue. Ann Derm Syph (Paris) 1914: 5:1-18.
Baughman RA. Median rhomboid glossitis: a developmental anomaly? Oral Surg Oral Med Oral Pathol 1971; 31:56-65.
Bouquot JE, Gundlach KKH. Odd tongues: the prevalence of common tongue lesions in 23,616 white Americans over 35 years of age. Quint Internat 1986; 17:719-730.
Allen CM. Animal models of oral candidiasis: a review. Oral Surg Oral Med Oral Pathol 1994; 78:216-221.
Brown RS, Krakow AM. Median rhomboid glossitis and a kissing lesion of the palate. Oral Surg Oral Med Oral Pathol Oral Radiol Endodont 1996; 82:472-473.
Table 1: Gender-specific prevalence rates per 1,000 population for selected oral masses and surface alterations in U.S. adults, ranked by total frequency. Modified from Bouquot JE. Common oral lesions found during a mass screening examination. J Am Dent Assoc 1986; 112:50-57, and Bouquot JE, Gundlach KKH. Oral exophytic lesions in 23,616 white Americans over 35 years of age. Oral Surg Oral Med Oral Pathol 1986; 62:284-291.
* total examined population = 23,616 adults over 35 years of age
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