A case of an ameloblastic fibro-odontoma arising from a calcifying odontogenic cyst

Developing odontoma arising from calcifying odontogenic cyst: A case report

Developing odontoma is a rare mixed odontogenic tumor that can arise with other odontogenic lesions. The association of COC with ameloblastic fibro-odontoma is extremely rare. We report an extremely rare case of developing odontoma arising from a calcifying odontogenic cyst in a 17-year-old girl.

Unusual microscopic changes of Ameloblastic Fibroma and Ameloblastic Fibro-odontoma: A systematic review

Background

Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO) are uncommon benign mixed odontogenic neoplasms. Although unusual microscopic changes including hybrid tumors have been documented in publications, their clinical outcome prediction and treatment modality selection are still challenging due to scarcity. Objective: Analysis of AF/AFO’s unusual microscopic variants in order to improve histopathologic diagnosis and to help clinicians in making informed treatment choices.

Material and Methods

An electronic search was performed in PubMed’s database using keywords: “ameloblastic fibroma”, “ameloblastic fibroodontoma”, “ameloblastic fibro-odontoma”. The search scheme was limited to articles in English, dated ‘January 1998’ to ‘October 2018’, with full texts (case reports and series) and human studies. Eligibility criteria included publications having enough clinical, radiological, and histological data to confirm their diagnosis. Age, sex, lesions’ location, radiologic features, signs, symptoms, treatment approaches, and recurrences were recorded and analyzed.

Results

In this systematic review, 11 articles (reporting 14 cases) were selected. Patients’ mean age was 13.75 years (male/female = 1.8). The posterior region of the mandible was the lesions’ commonest location (57.14%). Swelling was reported in 78.57% of the cases, pain in 28.57% but 21.42% were asymptomatic. Radiolucent unilocular appearance was the commonest radiographic feature, but 28.57% of the cases showed a mixed radiolucent-radiopaque appearance. Other reported radiographic findings were impacted tooth (78.57%), root resorption (28.57%), tooth mobility (35.71%), and cortical perforation (14.28%). No recurrences were reported. Calcifying odontogenic cyst (COC) was the commonest lesion associated with AF/AFO (53.33%). Unicystic ameloblastoma and cystic changes without prominent epithelial lining were other reported hybrid lesions. Reported microscopic variations were pigmentation and ghost cell differentiation.

Conclusions

COC was the commonest lesion associated with AF/AFO. Although COC commonly occurs in the jaws’ anterior region, hybrid cases were more common in the posterior area. No malignant transformations were reported. The treatment modality is mostly chosen based on the lesion’s most aggressive part.

Key words:Ameloblastic fibroma, Ameloblastic fibro-odontoma, Odontogenic tumor, Jaw.

Adenoid ameloblastoma: clinicopathologic description of five cases and systematic review of the current knowledge

OBJECTIVE

To describe the clinicopathologic and immunohistochemical features of five cases of adenoid ameloblastoma.

STUDY DESIGN

Clinicopathologic data were gathered from medical records and compared with those compiled from a systematic review. Slides were also immunohistochemically stained for Ki-67, p16, p53, and cytokeratins (7, 8, 14, 18, and 19).

RESULTS

There were 3 males (60%) and 2 (40%) females. The mean age was 44 ± 10 years. Of the five adenoid ameloblastomas, 4 (80%) occurred in the posterior maxilla. Patients typically complained of asymptomatic swelling. All patients received surgical resection as primary therapy; 1 (20%) patient also received adjuvant radiotherapy. Recurrence was diagnosed in all patients. Immunohistochemically, the tumors stained focally positive for CK7, 8, 14, and 18 and diffusely positive for CK-19, p16, and p53. The mean Ki-67-positive cells were 72.4 ± 24.9 positive cells per high-power field (range 53-111).

CONCLUSIONS

To our knowledge, this is the largest series of adenoid ameloblastoma reported in the literature. Our data suggest that this entity demonstrates aggressive behavior characterized by a high likelihood of recurrence.

Ghost cell lesions

Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.

Report of Two Cases of Combined Odontogenic Tumors: Ameloblastoma with Odontogenic Keratocyst and Ameloblastic Fibroma with Calcifying Odontogenic Cyst

Combined odontogenic neoplasms have rarely been documented. Such tumors have also been described by other researchers as "hybrid" lesions. The histologic features are often identical to other individually well-established odontogenic neoplasms such as ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma (AF), and ameloblastic fibro-odontoma. Their clinical presentation is variable, ranging from cysts to neoplasms showing varying degrees of aggressive behavior. Most combined tumors contain features of one of the odontogenic tumors in combination with either a calcifying odontogenic cyst (COC) or a calcifying epithelial odontogenic tumor. We present two new cases of combined odontogenic tumors: an ameloblastoma with an odontogenic keratocyst and an AF with COC. Predicting clinical outcome is challenging when a combination tumor is encountered due to the paucity of such lesions. One must understand salient features of these entities and differentiate them from the more common conventional neoplasms to expand classification and provide prognostic criteria.

Effectiveness of surgical decompression in the treatment of a calcifying cystic odontogenic tumor

The calcifying odontogenic cystic tumor (CCOT) is a benign lesion of odontogenic origin characterized by an ameloblastoma-like epithelium with ghost cells that may calcify. Despite broadly considered as a cyst, some investigators prefer to classify it as a neoplasm. Clinically, it occurs predominantly during the third decade of life. No difference in gender prevalence has been observed nor predilection of the lesion between maxilla and mandible. The most affected region extends from the incisor tooth to bicuspids. The classic treatment of the lesion is full excision, although a different approach may be determined by the possible association with another odontogenic tumor. Depending on the tumor size and the vicinity with important structures, decompression may be undertaken before its complete removal. The present report describes a case of CCOT with large proportions, located at the right maxilla and extending to the maxillary sinus, nasal cavity, and orbital floor. The treatment option was surgical decompression as the initial procedure, with satisfactory outcome. After partial remission, the lesion was fully removed, and the post-operative follow-up was uneventful.

Notch signaling and ghost cell fate in the calcifying cystic odontogenic tumor

Notch signaling is an evolutionarily conserved mechanism that enables adjacent cells to adopt different fates. Ghost cells (GCs) are anucleate cells with homogeneous pale eosinophilic cytoplasm and very pale to clear central areas (previous nucleus sites). Although GCs are present in a variety of odontogenic lesions notably the calcifying cystic odontogenic tumor (GCOT), their nature and process of formation remains elusive. The aim of this study was to investigate the role of Notch signaling in the cell fate specification of GCs in CCOT. Immunohistochemical staining for four Notch receptors (Notch1, Notch2, Notch3 and Notch4) and three ligands (Jagged1, Jagged2 and Delta1) was performed on archival tissues of five CCOT cases. Level of positivity was quantified as negative (0), mild (+), moderate (2+) and strong (3+). Results revealed that GCs demonstrated overexpression for Notch1 and Jagged1 suggesting that Notch1Jagged1 signaling might serve as the main transduction mechanism in cell fate decision for GCs in CCOT. Protein localizations were largely membranous and/or cytoplasmic. Mineralized GCs also stained positive implicating that the calcification process might be associated with upregulation of these molecules. The other Notch receptors and ligands were weak to absent in GCs and tumoral epithelium. Stromal endothelium and fibroblasts were stained variably positive.

Computerized tomography observation of a calcifying cystic odontogenic tumor with an odontoma: case report

The calcifying cystic odontogenic tumor is a rare benign odontogenic lesion. This report documents a case of this lesion associated with odontoma arising from the anterior maxilla in a 14-year-old boy. The diagnosis was confirmed based on computerized tomography findings, which clearly depicted the internal structures obscured in conventional images.

Calcifying odontogenic cyst with ameloblastic fibroma: Report of three cases

Although it is a rare event, odontogenic tumors such as ameloblastoma, ameloblastic fibroma (AF), ameloblastic fibro-odontoma, and odontoma have been reported associated with calcifying odontogenic cyst (COC). There are only four cases of COC with AF cited in the English literature. However, three of these four cases were either included in a review of a series of cases or reported as an abstract, and limited clinical and histological information was provided. We present three additional cases of COC with AF and discuss the management for this combined lesion. Because COC is known for its histologic diversity and variable clinical behavior, and the clinical significance of an association of COC with AF is still unknown, we think it is valuable to report COC with AF with detailed clinical and pathological documentation.

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.

Clinicopathologic spectrum of the so-called calcifying odontogenic cysts: a study of 21 intraosseous cases with reconsideration of the terminology and classification

The so-called calcifying odontogenic cyst (COC) represents a heterogeneous group of lesions that exhibit a variety of clinicopathologic and behavioral features. Because of this diversity, there has been confusion and disagreement on the terminology and classification of these lesions. We reviewed the clinicopathologic features of 21 intraosseous cases that were previously diagnosed as COC or under related diagnostic terms. Based on the biologic behavior, the lesions of the present series were divided into three subgroups: cyst, benign tumor, and malignant tumor. Sixteen cases (nine men and seven women) proved to be unicystic lesions with (five cases) or without associated odontoma. The lining epithelium of the cystic lesions fulfilled the histologic criteria for COC proposed by the World Health Organization, and their overall clinicopathologic features were consistent with that of developmental odontogenic cysts. The age of patients from the cyst group peaked at the second decade. The maxilla was affected more often (69%) than the mandible, with a predilection for the canine-premolar region (62.5%). Thirteen patients with follow-up information revealed no recurrence following enucleation. The four cases in the benign tumor group had variable clinicopathologic features. Two cases were solid tumors consisting of ameloblastoma-like sheets of odontogenic epithelium that contained ghost cells/calcification foci and juxtaepithelial dentinoid. Both patients experienced multiple recurrences following conservative surgeries. The other two lesions contained typical areas of COC and other types of odontogenic tumors (one ameloblastoma and one odontogenic myxofibroma). All four lesions occurred in the mandible and were relatively large. In the present series one case identified as malignant tumor arose from a previously benign COC. The tumor shared some features of COC (ghost cell foci and dystrophic calcification) but also had prominent mitotic activity, nuclear and cytoplasmic pleomorphism, areas of tumor necrosis, and infiltrative/destructive growth. Recognizing the extreme diversity in clinicopathologic features and biologic behavior among the so-called COCs, we suggest that the term COC should be used to specifically designate the unicystic lesions with or without an associated odontoma, i.e., lesions of the cyst group, and other related lesions identified as benign tumor and malignant tumor should be termed and classified separately. A tentative scheme with respect to the terminology and classification for this group of disparately behaving lesions was herein proposed to reflect the likely difference of their nature.