Glandular Odontogenic Cyst:
A Case Report
and Review of the Literature

Jean E. Binda, BA*; Robert Kuepper, DDS**; Carla Pulse, DDS***


ABSTRACT

Glandular Odontogenic Cyst (GOC) is a rare odontogenic cyst with unique histopathologic features and an unclear histogenesis. This is a case report of a recurrent glandular odontogenic cyst. A brief review of the clinical and diagnostic aspects of a glandular odontogenic cyst is also presented. (Col Dent Rev 2:1, 1997)

INTRODUCTION

In 1987, Padayechee and Van Wyk first described a unique cyst of the jaws which did not fit into the standard classification of odontogenic cysts and tumors. Due to its unique histopathologic features, they suggested the term sialo-odontogenic cyst to denote a possible origin or association with salivary gland tissue. In 1988, Gardner et al reported the first series of these cysts and used the name glandular odontogenic cyst, stating that the presence of mucous cells in the cyst lining did not imply an origin from salivary glands.3 Glandular odontogenic cyst remains the more popular term to date and is the name recognized by the WHO in 1992 to describe this new pathologic entity. It was classified as a developmental odontogenic cyst, although controversy still exists regarding terminology and origin. GOCs are relatively rare, with only twenty-three cases reported in the literature.1,4,6,7 They do appear to be odontogenic in origin and present as a well defined radiolucent swelling of the jaws with a tendency to recur following conservative treatment. They occur over a wide age range with no gender, race or ethnic predilection. The histopathologic features of this cyst have been described as a combination of findings from a botryoid odontogenic cyst and a mucoepidermoid carcinoma, often causing a diagnostic dilemma for pathologists.7 The purpose of this article is to present the twenty-fourth case of GOC, a recurrent case, with a brief literature review.

CASE REPORT

In May 1994, a 38 year old asymptomatic male was referred to the oral surgeon for evaluation of a 1.0 x 2.5 cm well delineated unilocular radiolucency between teeth #23 and #24. The lesion was causing root divergence of the involved teeth. Clinical examination revealed a somewhat compressible labial cortex with the involved mucosa exhibiting a bluish hue. Under local anesthesia, an excisional biopsy was performed and sent to a hospital laboratory for histologic examination. A diagnosis of a cyst, consistent with a radicular cyst, was made then. On follow-up examination, the lesion decreased in size demonstrating some bone fill. The patient was then referred back to his general dentist for routine care.

In November 1996, a routine examination revealed a 1.7 x 1.1 cm radiolucency, again involving teeth #23 and #24 with slight root displacement (Figure 1). The patient was asymptomatic and clinical examination was unremarkable. He was sent for endodontic therapy for teeth #23 and #24, and subsequently referred to the oral surgeon for excision of the apparent recurrent cyst. Under local anesthesia, the current lesion was surgically excised and submitted to the oral diagnostic biopsy service for histologic examination.

Figure 1.

Histologic findings revealed a cystic structure having elongated thin walls of fibrous connective tissue and an epithelial lining of varying thickness. The epithelial lining contained squamous and mucin bearing areas ( Figure 2 ). The surface exhibited occasional eosinophilic cuboidal cells ( Figure 3 ). There was some atypism manifested by focal loss of orderly stratification as well as mild focal hyperchromatism restricted to the epithelial lining. A review of histologic sections of the original cyst from 1994 showed the same histology as the current lesion. Therefore, our case was diagnosed as a recurrent glandular odontogenic cyst (sialo-odontogenic cyst) with epithelial lining atypism.

Figure 2: Photomicrograph showing a cystic lining consisting of stratified squamous epithelium with numerous plaque-like epithelial thickenings projecting
into the lumen. ( H & E stain: original magnification 63x )

Figure 3: Part of cyst wall lined by a layer of thickened epithelium containing mucus-secreting cells. The superficial epithelial layer consists of eosinophilic cuboidal cells. (Hematoxylin-eosin original magnification 200x )



DISCUSSION

The current lesion fulfills the diagnostic criteria for GOC proposed by Gardner et al.3 The histopathologic findings which should be detected are as follows: (1) a cystic cavity lined by epithelium of varying thickness with a flat interface between the epithelium and underlying connective tissue, (2) variable numbers of mucous cells in the epithelium, (3) eosinophilic cuboidal cells in the superficial layer, (4) localized plaque-like thickenings of the epithelium, (5) little inflammation, (6) occasional findings of hyperchromatic basal cells within the cyst lining. Our case also exhibited additional histologic features suggesting an aggressive nature. These features consisted of hyperchromatic cells outside the basal cell zone in the epithelial cyst lining, as well as some loss in the normal stratification of the epithelium. Initial descriptions of GOC described a lesion with histopathologic features of both the botryoid odontogenic cyst (the multilocular variant of lateral periodontal cyst) and a low-grade central mucoepidermoid carcinoma.5 Since this covers a fairly wide histologic spectrum, it is sometimes very difficult to differentiate a glandular odontogenic cyst from a predominantly cystic mucoepidermoid carcinoma, and may require careful analysis of several sections of tissue. From the limited number of cases reported, glandular odontogenic cysts appear to occur most commonly in the anterior mandible, although there have been case reports involving the maxilla.4 The most common form of clinical presentation is a slow growing swelling. Pain is very unusual but has been reported. The radiographic appearance may be a unilocular or multilocular well circumscribed radiolucency. Over half of the reported cases occurred in patients between 40 and 60 years of age,4 although the age range is wide, ranging from 14-80 years of age. The majority of GOC's have been treated conservatively, usually by enucleation and curettage.7 Few cases reported in the literature included an adequate follow-up period. Those that did (with an average follow-up of 5 years) showed a tendency towards recurrence, with some investigators citing a recurrence rate as high as 55%. Recurrence may be partly related to the thinness of the cyst wall and to the presence of microcysts making complete removal difficult. It may also be due to the traditional conservative treatment which may be inadequate, leading some investigators to suggest local block excision as a better treatment choice.2 No matter what method is used for treatment of these cysts, it is advisable to follow the patient several years for recurrent disease, which has been reported as long as 7 years after original treatment.5

CONCLUSION

The separate entity of glandular odontogenic cyst has been established only recently. Due to the paucity of case reports, there are many questions remaining to be resolved concerning histogenesis, biologic behavior and appropriate treatment of these lesions. The somewhat aggressive nature of GOC has been suggested in some reports,7 including the current case. The unique histopathologic features of this entity often present diagnostic challenges for pathologists due to the histologic overlap with other established lesions. Because of the scarcity of cases with long term follow up, the prognosis of this cyst remains unclear. Therefore, it is imperative that patients be followed carefully. Analyses of additional cases of this rare odontogenic lesion may add clarity to our current understanding of the glandular odontogenic cyst.

REFERENCES

1. DeCarvalho Y, Kimaid A, Cabral L, DeOliveira Nogueira T (1994) The glandular odontogenic cyst: a case report. Quintessence Int. 25: 351-354.
2. Ficarra G, Chou L Panzoni E (1990) Glandular odontogenic cyst (sialo-odontogenic cyst). Int. J. Oral Maxillofacial Surgery 19: 331-333.
3. Gardner DG, Kessler H, Morency R, Schaffner D (1988) The glandular odontogenic cyst: an apparent entity. J. Oral Pathology 17: 359-366.
4. Hussain K, Edmondson H, Browne R (1995) Glandular odontogenic cyst: diagnosis and treatment - Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics 79: 593-602.
5. Padayachee A, Van Wyk CW (1987) Two cystic lesions with features of both the botryoid odontogenic cyst and the central mucoepidermoid tumour: sialo-odontogenic cyst? J. Oral Pathology 16: 499-504.
6. Simba I, Kitano M, Mimura T, Sonoda S, Miyawaki A (1994) Glandular odontogenic cyst: analysis of cytokeratin expression and clinicopathological features. J. of Oral Pathology and Medicine 23:377-382.
7. Toida M, Nakashima E, Okumura Y, Tatematsu N (1994) Glandular odontogenic cyst: a case report and literature review. J Oral Maxillofacial Surgery 52: 1312-1316.