International collaborative study on ghost cell odontogenic tumours: calcifying cystic odontogenic tumour, dentinogenic ghost cell tumour and ghost cell odontogenic carcinoma

Background:  Calcifying odontogenic cyst was described first by Gorlin et al. in 1962; since then several hundreds of cases had been reported. In 1981, Prætorius et al. proposed a widely used classification. Afterwards, several authors proposed different classifications and discussed its neoplastic potential. The 2005 WHO Classification of Odontogenic Tumours re-named this entity as calcifying cystic odontogenic tumour (CCOT) and defined the clinico-pathological features of the ghost cell odontogenic tumours, the CCOT, the dentinogenic ghost cell tumour (DGCT) and the ghost cell odontogenic carcinoma (GCOC).
Methods:  The aim of this paper was to review the clinical-pathological features of 122 CCOT, DGCT and GCOC cases retrieved from the files of the oral pathology laboratories from 14 institutions in Mexico, South Africa, Denmark, the USA, Brazil, Guatemala and Peru. It attempts to clarify and to group the clinico-pathological features of the analysed cases and to propose an objective, comprehensive and useful classification under the 2005 WHO classification guidelines.
Results:  CCOT cases were divided into four sub-types: (i) simple cystic; (ii) odontoma associated; (iii) ameloblastomatous proliferating; and (iv) CCOT associated with benign odontogenic tumours other than odontomas. DGCT was separated into a central aggressive DGCT and a peripheral non-aggressive counterpart. For GCOC, three variants were identified. The first reported cases of a recurrent peripheral CCOT and a multiple synchronous, CCOT are included.
Conclusions:  Our results suggest that ghost cell odontogenic tumours comprise a heterogeneous group of neoplasms which need further studies to define more precisely their biological behaviour.     

Aggressive (malignant?) epithelial odontogenic ghost cell tumor

Although the calcifying odontogenic cyst (COC) is a well-established pathologic entity, it has been recognized that there is an odontogenic neoplasm with histologic features similar to the COC that has often been diagnosed as COC. Investigators have applied several terms to this neoplasm, but we prefer the term epithelial odontogenic ghost cell tumor (EOGCT). No reports have appeared previously in the literature describing either carcinoma arising in a COC or malignant EOGCT. Three cases are reported here with aggressive growth and histologic features strongly implying a malignant potential, although none is known to have metastasized. Two occurred in the maxilla and one in the mandible. One was discovered 9 years following removal of a typical COC, and another recurred rapidly after excision.     

The calcifying ghost cell odontogenic tumor – or the calcifying odontogenic cyst

Abstract. The paper reports on two new cases of calcifying odontogenic cysts, and gives a survey of 50 cases reported in the literature. In one case the ultrastructure of the characteristic ghost cells was examined. Most of the cells were anuclear or contained pyknotic nuclei. The only organelles found were very thick electro-dense fibrils of uniform size sharply defined against large empty spaces. Small needle-like crystalloid structures were seen in most cells. The ghost cells lying free in the connective tissue or embedded in the osteiod material had either lost their plasma membranes entirely or only remmants of it could be found. Histologically there is a marked similarity between the published cases. The epithelium forming either cysts or islands shows a distinct basal layer of columnar cells. Above the basal layer the cells are often stellate. Ghost cells are observed. Scattered both in the epithelium and in the surrounding connective tissue. Outeoid or dentinoid material was observed close to the ghost cells in 14 of 36 cases. Calcified deposits have been described in the ghost cells in 26 out of 36 cases reported. The material demonstrates an almost equal sex distribution of the tumor, and an almost equal distribution between the anterior maxilla and mandible. Two-thirds of the tumors were intra-osseous, and one-third were extra-osseous. The tumor occurs in all age groups, with an increased incidence in the age group of 10–19 years. There is no similarity between the clinical features of this lesion and those of ameloblastoma and calcifying odontogenic tumor.
The authors interpret the lesion as a tumor or hamartoma with a marked tendency for cystic degeneration. Therefore the designation calcifying ghost cell odontogenic tumor has been proposed.     

Ameloblastoma ex calcifying odontogenic cyst (dentinogenic ghost cell tumor)

Calcifying odontogenic cyst (COC) has shown to be of extensive diversity in its clinical and histopathological features, as well as in its biological behavior. In this report, a rare case is described of ameloblastoma ex COC (dentinogenic ghost cell tumor) and the relevant literature is briefly reviewed.     

基质金属蛋白酶及其组织抑制剂在牙本质生成性影细胞瘤和牙源性影细胞癌中的表达

目的 对牙本质生成性影细胞瘤(dentinogenic ghost cell tumor,DGCT)和牙源性影细胞癌(ghost cell odontogenic carcinoma,GCOC)中基质金属蛋白酶(matrix metallopmteinases,MMP)和金属蛋白酶组织抑制剂(tissue inhibitors of metalloproteinase,TIMP)的表达特点进行研究.方法 免疫组织化学分析15例DGCT和9例GCOC中MMP-2、MMP-9、MMP-14、TIMP-1和TIMP-2的表达.对DGCT和GCOC各一例分析MMP-2、MMP-9、MMP-14、TIMP-1和TIMP-2 mRNA的表达;明胶酶谱分析MMP-2和MMP-9酶原和活化蛋白的表达.结果 MMP-9和TIMP-1在GCOC中高表达(7/9,8/9);TIMP-1在GCOC中的高表达,与在DGCT中相比差异具有统计学意义(P＜0.05).对一例DGCT和一例GCOC病例研究发现,MMP-9酶原和活酶在GCOC中高表达,并且MMP-9和TIMP-1 mRNA在GCOC中高表达.结论 MMP-9和TIMP-1可能与GCOC的性质和生物学行为有关.     

Odontogenic ghost cell tumour with clear cell components: clear cell odontogenic ghost cell tumour?

A case of odontogenic ghost cell tumour (OGCT) with clear cell components was encountered in the mandible of a 63-year-old man. The tumour revealed ameloblastomatous-type epithelial components accompanied by clusters of ghost cells and dentinoid juxtaposed to the odontogenic epithelium. In addition, some areas of the tumour tissue showed sheets and islands of clear, glycogen containing epithelial cells, which were separated by a thin fibrous connective tissue stroma. Both ameloblastic and clear cells exhibited positive immunoreactivities for cytokeratin 19 and AE1/3. It is not known whether this tumour represents a clear cell change of a pre-existing OGCT or a separate and distinct neoplasm derived de novo from the odontogenic epithelium. This tumour was given the term 'clear cell OGCT' because it captures the clear cell components, which is one of the most prominent distinguishing features of the tumour.     

Hybrid odontogenic tumor of calcifying odontogenic cyst and ameloblastic fibroma

Odontogenic tumors composed of 2 distinct types of lesions are unusual. We report an odontogenic tumor that was composed of calcifying odontogenic cyst and ameloblastic fibroma that occurred in the right posterior maxilla of a 22-year-old Korean woman. The tumor had a cystic component with an ameloblastic epithelial lining and conglomerates of so-called ghost cells, and there were deposits of dentinoid material adjacent to the cyst. These are features characteristic of calcifying odontogenic cyst. Enamel organ-like epithelial islands were observed within a dental papilla-like stroma of the cyst wall. Additionally, a solid portion of the tumor had characteristic features of ameloblastic fibroma, i.e., a myxoid cellular stroma with numerous elongated islands of ameloblastic epithelium. Ghost cell masses were found in the area of ameloblastic fibroma as well. The distribution of the ghost cells suggests that this is a hybrid lesion rather than a collision tumor.     

Dentinogenic ghost cell tumor

A case of peripheral calcifying odontogenic cyst is presented. The nature of the lesion as a neoplasm is discussed including review of the literature. The terminology proposed for this lesion is "dentinogenic ghost cell tumor."     

Adenomatoid odontogenic tumor: a report of an unusual maxillary lesion.

Adenomatoid odontogenic tumor is an odontogenic tumor that appears in the anterior portion of the jaws and more frequently, in the anterior maxilla usually in association with the crowns of inclused teeth. A case report of adenomatoid odontogenic tumor with an associated impacted right maxillary first premolar is presented. Under general anesthesia the lesion and the impacted tooth were removed. There was no recurrence at the 1 -year follow-up.     

Central granular cell odontogenic tumor: a systematic review

Central granular cell odontogenic tumor (CGCOT) is a rare benign odontogenic neoplasm reported with various terms and is not included in the 2005 WHO classification of odontogenic tumors. It shows a predilection for middle‐aged women, usually presenting as an asymptomatic swelling of the mandibular premolar–molar region. Radiographic manifestations include unilocular or multilocular radiolucent lesion, but mixed density lesions can also occur. Histopathology shows sheets and lobules of round to polygonal cells with abundant eosinophilic, granular cytoplasm and eccentrically placed nuclei. Immunohistochemical and ultrastructural features suggest the histiocytic origin of granular cells. The neoplasm does not exhibit an aggressive biological behavior and hence enucleation or curettage ensuring complete removal remains the treatment of choice. We present a systematic review on clinical, radiological, histopathological, immunohistochemical and treatment aspect of CGCOT. Published articles were identified through a literature search using online databases (PubMed, MEDLINE, Scopus) and cross‐references for papers published from the year 1950 to March 2013. From a total of 37 papers, 26 (38 cases) were extracted from the database for systematic review.     

An unusual adenomatoid odontogenic tumor presenting as a residual cyst

An unusual case of adenomatoid odontogenic tumor of a 68-year-old edentulous man is presented. Clinically the lesion appeared to be a residual cyst of the maxillary canine region. This case varies from the norm with respect to age of the patient and clinical features.     

The dentinogenic ghost cell tumor

An unusual case and they of dentinogenic ghost cell tumor, a peculiar variant of calcifying odontogenic cyst, is reported. The tumor consisted predominantly of ghost cells with occasional areas of "dentinoid" in close proximity to masses of ghost cells. The presence of ameloblastoma-like nests of epithelium was characteristic of the present case and they were interpreted as a degenerative phenomenon exhibiting an inductive effect with formation of abundant ghost cells, occurring within a pre-existing ameloblastoma. The term of "dentinogenic ghost cell tumor" is employed for this unique lesion presented in this report. The literature describing the neoplastic potential of the calcifying odontogenic cyst is briefly reviewed.     

Peripheral dentinogenic ghost cell tumor

A case of dentinogenic ghost cell tumor, that has originated peripherally in the jaw, is presented and the literature reviewed with particular reference to the origin of the tumor. The total number of central and peripheral cases reported in the English literature is 10 and although mucosal infiltration is common, peripheral origin of the neoplasm could be verified in only 3 cases.     

The dentinogenic ghost cell tumor

An unusual case of dentinogenic ghost cell tumor, a peculiar variant of calcifying odontogenic cyst, is reported. The tumor consisted predominantly of ghost cells with occasional areas of "dentinoid" in close proximity to masses of ghost cells. The presence of ameloblastoma-like nests of epithelium was characteristic of the present case were interpreted as a degenerative phenomenon exhibiting an inductive effect with formation of abundant ghost cells, occurring within a pre-existing ameloblastoma. The term of "dentinogenic ghost cell tumor" is employed for this unique lesion presented in this report. The literature describing the neoplastic potential of the calcifying odontogenic cyst is briefly reviewed.