Calcifying epithelial odontogenic tumor: an immunohistochemical case study

CD1a is not effective in distinguishing calcifying epithelial odontogenic tumors from amyloid-rich central odontogenic fibroma

OBJECTIVE

Differential diagnosis between the non-calcifying variant of calcifying epithelial odontogenic tumor (NCLC-CEOT) and amyloid-rich central odontogenic fibroma (AR-COdF) has become a debate, particularly regarding the frequency of CD1a positivity in both entities. This has led to the growing consensus that CD1a-positive staining in AR-NC lesions confirms the diagnosis of AR-COdF. Here, we assess the validity of this consensus.

STUDY DESIGN

We collected the data of a case series of histopathologically distinct CEOTs, NCLC-CEOTs, and COdFs and stained them for CD1a and amyloid. Of the 9 CEOTs and NCLC-CEOTs, we diagnosed 4 as classic, 3 as associated with a dentigerous cyst, and 2 as combined CEOT/adenomatoid odontogenic tumors. Of the 9 COdFs, we diagnosed 3 as epithelial poor, 3 as epithelial rich (lacking amyloid), 2 as hyalinized with amyloid, and 1 as hyalinized without amyloid and assessed the staining results.

RESULTS

Of the 9 CEOTs and NCLC-CEOTs, 7 stained positively for CD1a, 5 diffusely and 2 focally. Notably, 2 classic NCLC-CEOTs stained strongly CD1a positive. All 3 of the epithelial-poor COdFs were predictably CD1a negative. Of the 6 remaining COdFs, 2 were CD1a positive, 1 hyalinized-with-amyloid COdF diffusely and 1 epithelial-rich-without amyloid focally.

CONCLUSIONS

CD1a positivity, which occurs in classic CEOT and NCLC-CEOT, does not help distinguish between NCLC-CEOT and AR-COdF and is inconsistent in all AR-COdFs. The diagnosis of CEOT and AR-COdF should be guided by appropriate histopathologic criteria irrespective of CD1a staining or the presence of amyloid or calcifications.

CEOT Variants or Entities: Time for a Rethink? A Case Series with Review of the Literature

The first detailed description of calcifying epithelial odontogenic tumor (CEOT) are ascribed to Jens Pindborg, but this tumor was described some years previously. Subsequently, CEOT was included in the 1971 WHO classification of odontogenic tumors and a since then number of variants have been described, which have added confusion to the diagnostic criteria. We aimed to survey the literature on the variants of CEOT, in parallel with a review of our single institution experience of CEOTs. Cases identified were collated, including available clinical, radiological and histological information and then reviewed, taking into account changes in the understanding and classifications of odontogenic tumors since initial diagnosis. We identified 26 cases from 1975 to 2017 for which histological material was available. Of these, only 13 (50%) showed the "classic" histological appearance, whilst two cases were identified as recognized variants. In 11 cases, other diagnoses or a differential diagnosis were preferred, with no agreed diagnosis in four of these. The proliferation fraction (Ki67) in the 10 cases tested was 2.1% ± 0.18. These findings illustrate the diagnostic challenges in this group of tumors and highlight the gaps in knowledge. Techniques, such as EWSR1 gene cytogenetic analysis, may be helpful in cases with clear cells. However, in other areas of controversy, including the non-calcifying and Langerhans cell rich variants, further investigation, perhaps utilizing sequencing technologies may be needed to refine the classification. Owing to the relative rarity of these lesions it would be beneficial if future work could be pursued as an international collaboration.

Ameloblastoma with adenoid features: A series of eight cases

BACKGROUND

Ameloblastoma with adenoid features are characterized by the presence of duct-like structures formed from the parenchyma of the tumor. This study was conducted to report a series of eight ameloblastomas with adenoid features, highlighting their clinicopathological and immunohistochemical aspects.

MATERIAL AND METHODS

Out of 71 cases of ameloblastomas, this study classified 8 cases as ameloblastomas with adenoid features. Clinicopathological data and immunohistochemistry for CK7, CK14, CK19, IMP3, p53 and Ki-67 were evaluated.

RESULTS

From those cases of ameloblastoma exhibiting adenoid features, there were 4 women and 4 men, with mean age of 39 years. Most cases affected the mandible and all presented radiographically as a radiolucency. The predominant histopathological features were pseudoducts, squamous metaplasia, nuclear hyperchromatism, clear cells, whorled aspect of epithelial structures, cribriform growth pattern, proliferation of spindle cells and extracellular eosinophilic material. Immunohistochemical analysis showed high expression for CK14 (n = 6) and CK19 (n = 3) and all cases (n = 8) were negative for p53, IMP3 and CK7. In addition, all samples (n = 8) showed low expression for Ki-67.

CONCLUSIONS

The similarities between the histopathological and immunohistochemical features of eight cases described in the present study and those described in previous studies support the possibility that these lesions are adenoid ameloblastomas. In addition, the immunohistochemical results of CK14, CK19, p53 and Ki-67 did not differ from those of conventional ameloblastomas.

Maxillary calcifying epithelial odontogenic tumor with sinus and buccal vestibule extension: a case report and immunohistochemical study

Background

Calcifying epithelial odontogenic tumor (CEOT) is a rare benign neoplasia, locally aggressive, that tends to invade bone and adjacent soft tissues. This case report describes the thirteenth known case of CEOT with maxillary sinus extension and the second one that also involves the buccal vestibule mucosa with peculiar histopathological and immunohistochemical data.

Case presentation

Here we report the case of a 45-year-old female with a CEOT diagnosed and treated at the Oral & Maxillofacial Surgery Department, County Clinical Emergency Hospital of Craiova, Romania. The clinical and imaging investigation revealed an intraosseous tumor developed from the left posterior maxilla with maxillary sinus and buccal vestibule mucosa extension. Histopathology found an epithelium-rich CEOT variant, but with scattered S100 positive clear cells, focal small rounded cementum-like deposits and areas with some degree of nuclear pleomorphism. The immunohistochemical investigations emphasised its local aggressiveness behavior with involvement of multiple molecular mechanisms that underlie tumor invasiveness. A subtotal maxillectomy was performed followed by defect reconstruction.

Conclusions

We discuss the relevant clinicopathological features of an aggressive rare case of CEOT with maxillary sinus extension and buccal vestibule mucosa involvement. The immunohistochemical study suggests its utility in attempting to assess the degree of local tumor aggressiveness and thus in adopting the most efficient therapeutic attitude.

Twist and Snail expression in tumor and stromal cells of epithelial odontogenic tumors

BACKGROUND

The aims of this study were to evaluate expression of Twist and Snail in tumor and stromal cells of epithelial odontogenic tumors and to analyze relationships between Twist and Snail expression and between tumor and stromal expression.

METHODS

Immunohistochemistry was performed using Twist and Snail antibodies in 60 ameloblastomas (AMs; 20 solid/multicystic, 20 unicystic, and 20 recurrent), six ameloblastic carcinomas (ACs), 10 adenomatoid odontogenic tumors (AOTs), and six calcifying epithelial odontogenic tumors (CEOTs).

RESULTS

A higher rate of tumor cells strongly positive for Twist was observed in AC compared to the other tumors (P = 0.019). The rate of tumor cells strongly positive for Snail tended to be higher in AC than in AM (P = 0.060). AM and AC showed a higher rate of Twist-positive stromal cells than AOT and CEOT (P < 0.001). Tumor cells of recurrent AM showed stronger expression of Twist (P < 0.001) and Snail (P = 0.001) compared to AM without recurrence. A moderate positive correlation was observed between tumor expression of Twist and Snail (r = 0.376, P = 0.001) and between tumor and stromal expression of Snail (r = 0.334, P = 0.002).

CONCLUSIONS

Twist and Snail may affect the epithelial-mesenchymal transition in AC and be involved in recurrence of AM. Stromal Twist expression may be associated with aggressive clinical behavior of epithelial odontogenic tumors. A Twist-Snail pathway may participate in the development and progression of odontogenic tumors, and tumor-stroma interaction in odontogenic tumors may be mediated by Snail.

Non-calcifying and Langerhans cell-rich variant of calcifying epithelial odontogenic tumor

This study reported the clinicopathological features, treatment and prognosis of nine cases of noncalcifying and Langerhans cell (LC)-rich calcifying epithelial odontogenic tumor (CEOT) collected from the English literature. Of the nine cases, seven were intraosseous and two were extraosseous. All nine tumors were found in Asian patients. The age of the nine patients ranged from 20 years to 58 years with a mean age of 41 years. There were five female and four male patients. The seven intraosseous cases included six in the anterior and premolar region of the maxilla and one in the posterior region and ascending ramus of the mandible. The two extraosseous cases were located at the upper lateral incisor and premolar gingivae, respectively. Of the seven intraosseous cases, five showed unilocular and two multilocular radiolucency without foci of calcification. Six of the seven intraosseous cases showed resorption of the tooth roots in the tumor-involved region. Histologically, noncalcifying and LC-rich CEOTs were composed of small nests and thin strands of tumor epithelial cells with a relatively high number of LCs among them. This was the reason why we classed these nine cases as noncalcifying and LC-rich CEOTs. Two extraosseous cases received total excision of the gingival mass. For the seven intraosseous cases, four accepted partial maxillectomy or mandibulectomy, two received total excision or enucleation, and one underwent curettage. The six cases with the follow-up information available showed no tumor recurrence after a follow-up period of 6 months to 10 years.

Current Concepts and Occurrence of Epithelial Odontogenic Tumors: II. Calcifying Epithelial Odontogenic Tumor Versus Ghost Cell Odontogenic Tumors Derived from Calcifying Odontogenic Cyst

Calcifying epithelial odontogenic tumors (CEOTs) and ghost cell odontogenic tumors (GCOTs) are characteristic odontogenic origin epithelial tumors which produce calcifying materials from transformed epithelial tumor cells. CEOT is a benign odontogenic tumor composed of polygonal epithelial tumor cells that show retrogressive calcific changes, amyloid-like deposition, and clear cytoplasm. Differentially, GCOTs are a group of transient tumors characterized by ghost cell presence, which comprise calcifying cystic odontogenic tumor (CCOT), dentinogenic ghost cell tumor (DGCT), and ghost cell odontogenic carcinoma (GCOC), all derived from calcifying odontogenic cysts (COCs). There is considerable confusion about COCs and GCOTs terminology, but these lesions can be classified as COCs or GCOTs, based on their cystic or tumorous natures, respectively. GCOTs include ameloblastomatous tumors derived from dominant odontogenic cysts classified as CCOTs, ghost cell-rich tumors producing dentinoid materials as DGCTs, and the GCOT malignant counterpart, GCOCs. Many authors have reported CEOTs and GCOTs variably express keratins, β-catenin, BCL-2, BSP, RANKL, OPG, Notch1, Jagged1, TGF-β, SMADs, and other proteins. However, these heterogeneous lesions should be differentially diagnosed to allow for accurate tumor progression and prognosis prediction.

A clinicopathologic study on calcifying epithelial odontogenic tumor: with special reference to Langerhans cell variant

BACKGROUND

Calcifying epithelial odontogenic tumour (CEOT) is a rare benign odontogenic tumour, and its Langerhans cell variant is even rarer. Due to the limited number of recorded cases, the biological behaviour and histogenesis of the Langerhans cell variant of CEOT are not yet fully understood. Thus, the correlation between conventional CEOT and the Langerhans cell variant remains to be clarified.

MATERIAL (CASES)

Eight cases of CEOT including 2 cases of Langerhans cell variant were clinicopathologically studied and the English language literature was reviewed. Langerhans cells were detected in 2 cases of conventional CEOT and in 2 cases of Langerhans cell variant by immunohistochemistry.

RESULTS AND FINDINGS

In the 6 cases of conventional CEOT, 5 tumours involved the premolar and molar region and the anterior portion of the mandible was affected in 1 case. Four patients were followed for 2-7 years and did not show any sign of recurrence. A review of the English language literature revealed 5 cases; combined with the present 2 new cases, a total of 7 cases of Langerhans cell variant of CEOT were collected. The patients were all Asian. Six tumours occurred in the maxilla and 1 in mandible; all mainly involved the anterior region of the jaws. Five patients were followed for 2-10 years and did not show any evidence of recurrence. Langerhans cells can be seen in both the conventional and the Langerhans cell variant of CEOT; however, increased numbers of Langerhans cells are seen in the latter.

CONCLUSIONS

Although the Langerhans cell variant of CEOT is a rare entity and behaves similarly to the conventional type, it could show unique clinical and histologic features that may pose problems for differential diagnosis.

VIRTUAL SLIDES

http://www.diagnosticpathology.diagnomx.eu/vs/1979090740113894.

Ulcerated anterior maxillary swelling showing radiopaque bodies on cone beam computed tomography

The calcifying epithelial odontogenic tumor (CEOT), also known as Pindborg tumor, is a rare benign tumor of epithelial origin of locally aggressive behavior, which represents less than 1% of all odontogenic tumors affecting the oral cavity. The lesion usually presents as a nonulcerated painless mass of slow growth, commonly affecting the posterior region of the mandible. Depending on the stages of development, CEOTs may present variable radiographic appearances. To date, a few number of cases affecting the anterior maxillary region have been published in the English-language literature. This article describes an interesting and rare case of an anterior ulcerated maxillary swelling diagnosed as a CEOT based on clinical, cone beam computed tomography and pathologic findings. Functional results were obtained with the surgical approach, and no recurrence of the lesion during a 2-year follow-up period was observed.

CD1a-positive Langerhans cells and their relationship with E-cadherin in ameloblastomas and keratocystic odontogenic tumors

BACKGROUND

Ameloblastomas and keratocystic odontogenic tumors (KOTs) are lesions that are characterized by locally invasive growth and cause extensive bone destruction. In addition, it is known that E-cadherin influences the adhesion of Langerhans cells (LCs) to keratinocytes.

OBJECTIVE AND METHODS

The aim of this study was to investigate, using immunohistochemistry, the distribution of CD1a-positive cells in ameloblastomas and KOTs and their relationship with E-cadherin, in comparison to calcifying cystic odontogenic tumor (CCOT).

RESULTS

The CD1a-positive LCs were observed in 11 ameloblastomas and KOTs. All of the cases of CCOT showed CD1a-positive LCs and a significant difference was found when this tumor was compared with ameloblastomas (P < 0.05, Mann-Whitney test). A statistically significant difference was also noted when comparing CD1a-positive LCs between CCOTs and KOTs (P < 0.05, Mann-Whitney test). Lower expression of E-cadherin in ameloblastomas (AMs) in relation to KOTs and CCOTs (P < 0.05, Fisher test) was observed. There was no correlation between E-cadherin and CD1a-positive LCs between all odontogenic tumors that were studied (P > 0.05, Spearman test).

CONCLUSION

A quantitative difference of CD1a-positive cells between AMs and KOTs in comparison to CCOTs was observed. This permits to speculate that a depletion of CD1a-positive LCs might influence the local invasiveness of ameloblastomas and KOTs. Furthermore, it is suggested that E-cadherin mediates cell adhesion in these tumors.

Investigation of basement membrane proteins in a case of granular cell ameloblastoma

Granular cell ameloblastoma is a rare, benign neoplasm of the odontogenic epithelium. A case of massive granular cell ameloblastoma in a 44-year-old Thai female is reported. Histopathological features displayed a follicular type of ameloblastoma with an accumulation of granular cells residing within the tumor follicles. After treatment by partial mandibulectomy, the patient showed a good prognosis without recurrence in a 2-year follow-up. To characterize the granular cells in ameloblastoma, we examined the expression of basement membrane (BM) proteins, including collagen type IV, laminins 1 and 5 and fibronectin using immunohistochemistry. Except for the granular cells, the tumor cells demonstrated a similar expression of BM proteins compared to follicular and plexiform ameloblastomas in our previous study, whereas the granular cells showed strong positivity to laminins 1 and 5 and fibronectin. The increased fibronectin expression in granular cells suggests a possibility of age-related transformation of granular cells in ameloblastoma.

Biochemical and immunohistochemical characterization of the amyloid in canine amyloid-producing odontogenic tumor

The amyloid of canine amyloid-producing odontogenic tumor (APOT) was evaluated biochemically and immunohistochemically. The N-terminal amino-acid sequence of purified amyloid protein from a canine APOT was strikingly similar to the sequence in both rat ameloblastin and porcine sheathlin. Immunohistochemically, the amyloid in APOT from 9 dogs was strongly reactive with anti-rat ameloblastin, anti-porcine sheathlin, and anti-canine APOT amyloid and weakly reactive with anti-porcine amelogenin but negative for antibodies to cytokeratins, vimentin, desmin, alpha-smooth muscle actin, amyloid A, glial fibrillary acidic protein, or S100 protein. The neoplastic epithelial cells of APOT were focally reactive with antibodies to ameloblastin, sheathlin, amelogenin, and canine APOT amyloid. The similarity in amino-acid sequence of the amyloid protein of canine APOT to that of enamel proteins, such as ameloblastin, sheathlin, and amelogenin, and the expression of these antigens in both APOT amyloid and in the neoplastic cells suggest that the amyloid of canine APOT is derived from enamel proteins secreted by ameloblasts.