Clear cell odontogenic carcinoma: report of three cases with pulmonary and lymph node metastases

Clear Cell Odontogenic Carcinoma: A Rare JAW Tumor-A Case Report and Literature Review

Clear cell odontogenic carcinoma (CCOC) is a rare epithelial malignant odontogenic tumor of the jaw with a distinct histology and deceptive behavior. As the clinical presentation is often misleading, the contribution of biopsy, molecular biology, immunohistochemistry and cytogenetics are essential in the diagnostic process. This article describes the presentation of an aymptomatic, painless swelling in the lower jaw of a 63 yrs old female, who was initially diagnosed as an ameloblastoma, taken up for segmental resection, subsequently histopathologically diagnosed as a case of clear cell odontogenic carcinoma and later managed with chemotherapy. Current management protocols and presentation of CCOC have also been reviewed.

Exuberant clear cell odontogenic carcinoma of the mandible harboring EWSR1 rearrangement: Report of a rare case and a literature review

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumour (MOT) that mainly affects the mandible, with a slight female predominance in adult patients. In this study, we described an exuberant CCOC in mandible of a 22-year-female patient. On radiographic examination, a radiolucent lesion in the region of tooth 36 to 44 with tooth displacement and alveolar cortical resorption was observed. Histopathological study revealed a malignant neoplasm of the odontogenic epithelium, composed of PAS-positive clear cells and immunoreactivity for CK5, CK7, CK19, p63. The Ki-67 index was low (<10 %). Fluorescent in situ hybridization revealed EWSR1 gene rearrangement. The diagnosis of CCOC was established and the patient was referred for surgical treatment.

Recurring Clear Cell Odontogenic Carcinoma Involving Vertebra and Pleura: A Case Report and Literature Review

Clear cell odontogenic carcinoma is a rare malignancy, which is vary in behavior from indolent tumor to cases with frequent recurrence and rare metastasis. In this manuscript, we report a case of clear cell odontogenic carcinoma of right lower mandible with cervical lymph node metastasis in a 50-year-old female. The tumor recurred and metastasized to vertebra and pleura after adjuvant radiation and chemotherapy, and the patient died of the disease 29 months after diagnosis. Pathologically, the tumor was composed of epithelial nests dominated by clear cells with ameloblastoma-like pattern and biphasic pattern. The tumor cells showed strong positive for AE1/AE3, KRT19, KRT5/6, P63, focal positive for KRT7, and weak positive for MUC1. Molecularly, EWSR1::ATF1 gene fusion was identified. To our knowledge, this report describes the first case of metastasis of clear cell odontogenic carcinoma involving regional lymph nodes and distant pleural and vertebral areas, demonstrating an aggressive clinical course of clear cell odontogenic carcinoma.

Malignant Odontogenic Tumours: A Systematic Review of Cases Reported in Literature

Background: Malignant odontogenic tumours (MOTs) arise either de novo from the tooth forming tissues, their developmental residues or from existing odontogenic epithelial or mesenchymal neoplasms in the jaws. Their management requires extensive surgery due to their infiltrative nature and risk of metastasis. There is a need to understand the clinical and pathological features of MOTs to inform both treatment algorithms and prognostication. This is an area of diagnostic pathology which presents substantial difficulties in diagnosis, compounded by inconsistent use of terminology. Thus, this systematic review aimed to describe the clinical and pathological features of MOTs with a view to consolidating the literature and defining problematic areas in diagnosis and classification. Methods: An electronic database search was conducted in Web of Science, PubMed/Medline, and Embase. Additionally, the grey literature and reference lists of selected papers searched for completeness. Nine hundred and sixty articles were initially identified. Following removal of duplicates and application of inclusion/exclusion criteria, 312 articles were included for qualitative analysis. Results: The 312 articles encompassed a total of 507 patients with most lesions located within the mandible (74.3%). The most common first histological diagnosis was ameloblastic carcinoma (25.7% of all diagnoses), but there is considerable variation in how and when various diagnostic terms are used, and several misdiagnoses were reported. An initial benign diagnosis was made in 24.7% of patients, followed by a later malignant diagnosis and in this sub-group, the most common benign first diagnosis was ameloblastoma (42.4%). Cervical lymph nodes were the most common site of metastasis (9.3% of patients). With respect to distant metastasis (DM), the lungs were the most common organ affected (11.2% of DM patients) with metastasising ameloblastoma the most commonly reported tumour which metastasised to the lungs. Overall, 26.8% of patients developed recurrence. Conclusion: Overall, the quality of the literature on MOTs is poor. This review of the literature has highlighted variations in diagnostic terms and criteria which has resulted in areas of confusion with potential for misdiagnosis. This consolidation of primary data has identified key areas for targeted research including further discussion on the malignant potential of ameloblastoma.

Clear Cell Odontogenic Carcinoma a Systematic Review

Clear cell Odontogenic Carcinoma (CCOC) is an uncommon malignant odontogenic tumor (MOT). It is the fifth most common MOT. A systematic review is presented of reported cases, case series and retrospective studies of CCOC, to determine trends in presentation, diagnostic features, treatment, and patient outcome. Searches of detailed databases were carried out to identify papers reporting CCOC. The variables were demographics, patient symptoms, tumor location, histopathological findings, immunohistochemical studies, treatment, follow-up, and recurrence. 117 cases were identified; CCOC was most frequently seen in mature females 65% (n = 76). The total average age was 55.4 with a range from 17 to 89 years, for females 56.4 and males 53.6 years. The mean size was 3.41 cm. The most common location was in the mandibular body 36.2% (n = 42), followed by the anterior mandible 23.3% (n = 27). The most common clinical presentation was a swelling 80.4% (n = 74), and the main symptom was pain 41.3% (n = 31), followed by painless lesion 24% (n = 18). The most common Immunohistochemistry positive expression was CK19, EMA, and CEA, and for special staining periodic acid Shiff (PAS); 97% of cases were treated surgically. The average follow-up was 30.3 months, and recurrence was reported in 52.4% of the cases. Conclusion: CCOC shows a strong predilection for the body and anterior mandible, and females are more frequently affected. CCOCs can be painful and the principle clinical sign is swelling, CCOCs can metastasize, and the prognosis is fair.

Rare clear cell odontogenic carcinoma associated with impacted tooth in a young patient: case report and literature review

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor. It is characterized by showing, on histopathological examination, clusters of vacuolated and clear tumor cells with epithelial differentiation surrounded by fibrocollagenous stroma and fibroblasts. The present study presents a rare clinical case of mandibular CCOC associated with an impacted tooth in a 26-year-old woman surgically treated with mandibulectomy and reconstruction with iliac crest bone graft. The patient has been followed up for 22 months without signs of recurrence. A search for case report/case series was carried out in the PUBMED database, as well as in the references of relevant previously published literature reviews. Ninety-six publications were identified, totaling 136 distinct cases reported. Female sex was the most affected (63.1%) with 63.3% of cases occurring in patients in the fifth, sixth, or seventh decades of life. The mandible was more affected than the maxilla (74.2%). Association of CCOC with impacted teeth was found in 2.4% of cases, thus rendering it a rare occurrence. The present case report corroborates the results of the survey regarding sex and anatomical location of the tumor; however, it contradicts the findings regarding age predilection. The case described is the fourth known occurrence of tooth impaction associated with the tumor and the first in a female. In conclusion, CCOC should be considered, as well as other malignancies, as a possible diagnosis of maxillary or mandibular intraosseous lesions even in unusual circumstances such as in association with impacted teeth and in young patients.

Clear cell odontogenic carcinoma: a rare jaw tumor. A summary of 107 reported cases

The purpose of this study was to summarize the currently published cases of clear cell odontogenic carcinoma (CCOC). The PubMed and Springer databases were used to collect available reports, searching for 'clear cell odontogenic carcinoma', 'CCOC', or 'clear cell ameloblastoma'. The search resulted in 75 reports detailing 107 cases between 1985 and 2018. Clinically the tumor manifests as a swelling in the posterior mandible (n=46), anterior mandible (n=33), and maxilla (n=28). Radiological analysis of 85 cases typically showed a poorly defined expansive radiolucency (n=83). Of the 70 patients with symptoms reported, 44 specified a swelling, 11 tooth mobility, seven gingival/periodontal issues, five numbness, and three decreased jaw opening. One patient presented with a neck mass. The duration of symptoms prior to seeking care was specified for 52 patients: 2 months to 1 year for 34 patients, 1-2 years for seven, 2-4 years for two, 4-7 years for six, and 7-12 years for three. The incidence of recurrence appeared to be 38 of the 88 cases where recurrence was reported. CCOC can be distinguished from other oral cancers by its distinctive histology and immunohistochemical characteristics and less aggressive behavior. Currently, treatment should be early and aggressive resection with clear surgical margins and long-term follow-up. The overall goal is to collect a cohort of patients.

Clear cell odontogenic carcinoma: Case report of a deceptive pathology

Clear cells are associated with numerous physiological and pathological conditions. Odontogenic cysts and tumors can arise from physiological clear cells like rests of dental lamina. One such clear cell neoplasm is clear cell odontogenic carcinoma (CCOC) that is associated with aggressive clinical behavior, metastasis and low survival rate. With <80 cases reported so far, it is a rare entity. Initially described as a clear cell odontogenic tumor considering it as a benign but invasive neoplasm, it was later termed as CCOC owing to its infiltrative nature with a marked tendency for local recurrence, regional nodal spread and possible distant, mainly pulmonary, metastasis. Reported here is a case of CCOC affecting mandible of a 55-year-old female along with its immunohistochemical workup.

Clear cell odontogenic carcinoma of the mandible: a treatment strategy

Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor of the jaws, histologically characterized by the presence of agglomerates of cells with eosinophilic cytoplasm. The patient, a 62-year-old Caucasian woman, presented an intraosseous lesion in the mandibular symphysis. A clinical examination revealed a discrete volumetric increase with a hard consistency, palpable to extraoral and intraoral examinations. Imaging studies revealed an extensive radiolucent area, without defined limits, extending from the region of the right second premolar to the left canine. Incisional biopsy analysis indicated a diagnosis of CCOC. The treatment proposed was segmental resection of the mandible with a safety margin. After six months without recurrence, definitive mandibular reconstruction was performed using an iliac crest graft, followed by rehabilitation with implant-supported denture after five months. After three years of post-resection follow-up, the patient has shown no evidence of recurrence or metastasis. She continues to be under follow-up. To conclude, CCOC must be considered a malignant tumor with aggressive behavior. Previous studies have shown that resection with free margins is a treatment with a lower rate of recurrence. Nevertheless, long-term follow-up is necessary for such patients.

Establishment and characterization of a clear cell odontogenic carcinoma cell line with EWSR1-ATF1 fusion gene

OBJECTIVE

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor (MOT) characterized by sheets and lobules of vacuolated and clear cells. To understand the biology of CCOC, we established a new cell line, CCOC-T, with EWSR1-ATF1 fusion gene from a mandible tumor with distant metastasis and characterized this cell line.

MATERIALS AND METHODS

To detect the EWSR1-ATF1 fusion gene, we used three CCOC cases, including the present case, by RT-PCR and FISH analysis. We characterized established CCOC-T cells by checking cell growth, invasion and the expression of odontogenic factors and bone-related factors. Moreover, the gene expression profile of CCOC-T cells was examined by microarray analysis.

RESULTS

Histologically, the primary tumor was comprised of cords and nests containing clear and squamoid cells separated by fibrous septa. In addition, ameloblastomatous islands with palisaded peripheral cells were observed, indicating probable odontogenic origin. This tumor expressed the fusion gene EWSR1-ATF1, which underlies the etiology of hyalinizing clear cell carcinoma (HCCC) and potentially that of CCOC. We found a breakpoint in the EWSR1-ATF1 fusion to be the same as that reported in HCCC. Established CCOC-T cells grew extremely slowly, but the cells showed highly invasive activity. Moreover, CCOC-T cells expressed bone-related molecules, odontogenic factors, and epithelial mesenchymal transition (EMT)-related molecules.

CONCLUSION

To the best of our knowledge, this is the first report on the establishment of a CCOC cell line. CCOC-T cells serve as a useful in vitro model for understanding the pathogenesis and nature of MOT.

Clear cell odontogenic carcinoma: report of 7 new cases and systematic review of the current knowledge

OBJECTIVE

The goal of this study is to describe 7 cases of clear cell odontogenic carcinoma among a Brazilian population and compare these data with a systematic review of the English-language literature.

STUDY DESIGN

Descriptive statististics were used to compare the clinicopathologic data gathered retrospectively with those compiled from a review. Tumor sections were immunostained for Ki-67, p16, p53, and cytokeratins (CKs) 7, 8, 14, 18, and 19. Log-rank tests were performed for survival analysis.

RESULTS

Most cases occurred in the posterior mandible (5/7, 71.4%), and recurrence was diagnosed in all treated patients. Metastatic disease occurred in 2 patients (28.6%). Tumors were focally positive for CKs 7, 8, 14, and 18 and diffusely positive for CK19, p53, and p16. The mean number of Ki-67-positive cells was 35.2 cells/high-power field. Our systematic review provided evidence that tumor size (P = .046), histologic pattern (P = .034), regional metastasis (P = .001), distant metastasis (P = .001), and local recurrence (P = .05) were of significant prognostic value.

CONCLUSIONS

This study has contributed to improved characterization of clear cell odontogenic carcinoma, which is an aggressive odontogenic malignant neoplasm diagnosed mainly in the posterior mandible of middle-aged women and typically at an advanced stage. Radical surgical procedures remain the gold standard treatment.

Cytomorphology and immunohistochemistry of a recurrent clear cell odontogenic carcinoma with molecular analysis: A case report with review of literature

Clear cell odontogenic carcinoma (CCOC) is a rare, odontogenic tumor of the jaws with mandibular involvement usually present in sixth decade of life with female preponderance. It is classified as a malignant tumor of odontogenic origin in 2005 by the World Health Organization because of its aggressive and destructive growth capacity and potential to metastasize. It needs to be distinguished from other primary and metastatic clear cell tumors of the oral and maxillofacial region. Recently, CCOCs have been noted to harbor a Ewing sarcoma breakpoint region 1 gene RNA-binding protein 1 (EWSR1) and activating transcription factor (ATF) gene translocation. To date, cytologic features of only one case have been reported in the literature. We report an additional case of 55-year-old woman with enlarging mass in the left mandible. This report describes cytologic and immunohistochemical features of CCOC with positive EWSR1 gene rearrangements by fluorescence in situ hybridization (FISH). As diagnosis of CCOC is challenging on fine-needle aspiration, immunohistochemistry and FISH analysis are very useful diagnostic tool in clear cell lesions of mandible.

Clear cell odontogenic carcinoma-a rare case report

Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumour with female predilection occurring in the anterior region of the mandible with peak age incidence of 5th and 7th decade of life. Here we report a case occurred in the posterior mandible of a 42 year old male patient which highlights the clinicopathologic features of CCOC that were confirmed by histopathologic examination. We add up yet another case of CCOC to the published literature.

Odontogenic carcinoma with dentinoid: a new odontogenic carcinoma

Dentinoid is an integral part of some odontogenic tumors. This article describes the clinico-pathological features of three cases of odontogenic carcinomas with dentinoid (OCD). A comparison of these with previously reported cases of dentinoid-producing epithelial odontogenic tumors allowed us to identify another six cases that may be considered as examples of OCD. Six cases occurred in the mandible and three in the maxilla, all developing behind the canines. There was no sex predilection (five men and four women; age range 14-61 years, mean 38.1). Pain or discomfort was mentioned in five cases, four of which showed tooth resorption. All cases appeared initially as well-defined radiolucencies, five of which showed variable amounts of calcified material. Recurrences were recorded in three instances, but no evidence of metastasis has been found. Seven cases were composed predominantly or entirely of clear cells, usually with minimal cellular atypia and variable mitotic activity; however, in all cases there was evidence of tumor infiltration into adjacent tissues, including the presence of perineural invasion in two tumors. Those cases in which no reference was made to the presence of clear cells exhibited evident mitotic activity and cellular pleomorphism. The epithelium in OCD does not produce buds or enamel organ-like structures such as those found in ameloblastic fibro-dentinoma and this tumor does not contain a mesenchyme-like connective tissue resembling dental papilla as observed in several mixed odontogenic tumors. Based on the existing data and the present series of cases, OCD appears to represent a distinct entity.

Clear cell odontogenic carcinoma mimicking a cystic lesion: a case of misdiagnosis

Clear cell odontogenic carcinoma (CCOC) is a rare jaw tumor that was classified as a malignant tumor of odontogenic origin in 2005 by the World Health Organization because of its aggressive and destructive growth capacity and metastasis to the lungs and lymph nodes. We report a case of a 66-year-old female who had swelling, incision and drainage history and a well-defined unicystic radiolucent lesion that was comparable to a cystic lesion. At first, the patient received decompression, and the lesion size decreased. Three months after decompression, cyst enucleation was performed. The pathologic result indicated that the lesion was CCOC. In this report we emphasize that patients with painful cystic lesions in addition to jaw enlargement and loosening teeth should be considered for the possibility of malignancy.

Pathogenesis and nomenclature of odontogenic carcinomas: revisited

Odontogenic carcinoma is rare group of malignant epithelial odontogenic neoplasms with characteristic clinical behavior and histological features, which requires an aggressive surgical approach. The pathogenesis of this rare group remains still controversial and there have been many varied opinions over the classification of this rare group of lesions. As there have not been many reviews on odontogenic carcinoma, the existing knowledge is mostly derived from the published case reports. This review is discussing the pathogenetic mechanisms and is updating the knowledge on nomenclature system of less explored odontogenic carcinomas. This review might throw light on the pathogenesis and nomenclature system of odontogenic carcinoma and this knowledge may be applied therapeutically.

An intraosseous sclerosing odontogenic tumor predominantly composed of epithelial cells: relation to (so-called) sclerosing odontogenic carcinoma and epithelial-rich central odontogenic fibroma

We report a case of an asymptomatic sclerosing odontogenic tumor in a 31-year-old woman. Radiologically, the tumor was well circumscribed, was predominantly radiolucent, and had a peripheral sclerotic margin. Histopathologically, the tumor showed small clusters, strands, and cords of small to medium-sized epithelial tumor cells in a sclerotic collagenous stroma. Immunohistochemically, the tumor cells were positive for broad-spectrum cytokeratins (CKs) (CK7, CK5/6, CK19, and CAM 5.2) and p63. Membranous staining for E-cadherin was present. There was weak to moderate nuclear expression of p16 in 30% of cells. Rare tumor cells were positive for p53. Progesterone receptors were expressed in about 60% of the tumor cells. The proliferative activity (Ki-67) was approximately 2%. A molecular genetic (fluorescence in situ hybridization) study showed no EWSR1 (EWS RNA-binding protein 1) gene rearrangement. No recurrence or metastatic events have been documented at 1-year follow-up. This tumor represents a classification dilemma mainly between epithelial-rich central odontogenic fibroma and the so-called sclerosing odontogenic carcinoma.

EWSR1 and ATF1 rearrangements in clear cell odontogenic carcinoma: presentation of a case

Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor of the jaws that is more common in the mandible than maxilla and has a female preponderance with a peak incidence in the sixth decade. It is characterized by locally aggressive behavior and has the potential to metastasize. This tumor was recently reported to have a rearrangement of the Ewing sarcoma breakpoint region 1 gene (EWS RNA-binding protein 1, EWSR1) in 5 of 8 cases tested and of the activating transcription factor 1 gene (ATF1) in 1 case tested. We report a case of CCOC in the premolar area of the mandible in a 59-year-old woman. This case demonstrated the presence of both EWSR1 and ATF1 gene rearrangements by fluorescence in situ hybridization.

Clear cell odontogenic carcinoma of maxilla: A case report and mini review

Clear cell odontogenic carcinoma is a rare odontogenic tumor occurring predominantly in posterior mandible during 5^th-7^th decades with a female predilection. It is a potentially aggressive tumor, capable of frequent recurrences and loco-regional and distant metastases. Till date, only 73 cases have been reported in the literature. Current case is of a 55-year-old woman with tumor mass extending from canine to molar region on the left maxillary arch. Being locally aggressive tumor with the capacity to metastasize, it demands to be distinguished from other primary and metastatic clear cell tumors of the oral and maxillofacial region. A brief compilation of the reported cases is being attempted in the current article to better understand the behavior of the tumor.

Clear cell odontogenic carcinoma: case report with immunohistochemical findings adding support to the challenging diagnosis

Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor associated with aggressive clinical behavior, metastasis, and low survival. We report a case of CCOC affecting the mandible of a 39-year-old man. The tumor presented a biphasic pattern composed of clear cell nests intermingled with eosinophilic cells and separated by collagenous stroma. Immunoreactivity to cytokeratin (CK), specifically AE1/AE3 and CK 8, 14, 18, and 19 was found, as well as to epithelial membrane antigen (EMA). The tumor cells were negative for S100 protein, CK 13, vimentin, smooth muscle actin, laminin and type IV collagen. Low labeling indices for the proliferation markers Ki-67 and proliferating cell nuclear antigen and to p53 protein might predict a favorable prognosis for the lesion. A surgical resection was performed, followed by adjuvant radiotherapy. A 2-year follow-up has shown no signs of recurrence. The significance of histochemical and immunohistochemical resources in the correct diagnosis of CCOC is analyzed.

Clear cell odontogenic carcinoma of the maxilla: a case report and literature review

BACKGROUND

Clear cell odontogenic carcinoma (CCOC) is a rare tumor of odontogenic origin. It was first described as a clinicopathological entity in 1985, and since then, several case reports have been published.

METHODS

We present a patient with CCOC treated at the University of Florida and review the pertinent literature.

RESULTS

We treated a 52-year-old woman with CCOC of the maxilla. She received a maxillectomy and postoperative radiotherapy (RT). She developed pulmonary metastases 2 years after treatment. She remains alive and asymptomatic 7 years after completing treatment and has not required additional therapy. The literature search yielded 48 other case reports. The median age at presentation was 53 years (mean, 55 years), the female-to-male ratio was 2:1, and the most common site of presentation was the mandible. Three patients presented with submandibular lymphadenopathy. Most patients had a surgical resection (35 patients, 71%); the remainder underwent curettage. Six (12%) patients received postoperative RT. Eighty percent of patients who were initially treated with curettage developed a local recurrence. Local and/or regional recurrences occurred in 34% of patients who underwent surgical resection. Six patients developed distant metastatic disease; the most common site of the metastases was the lung. Seven patients died from or with the disease, and 3 are alive with the disease.

CONCLUSIONS

Clear cell odontogenic carcinoma is a rare tumor of the mandible and maxilla that has the propensity for local destruction and the potential for lymphatic and hematogenous metastases. We recommend radical excision as the primary treatment and that adjuvant RT be added for those who have close or positive margins as well as those with lymph node metastases.

[Malignant odontogenic tumors]

Malignant odontogenic tumors are extremely rare. As with benign odontogenic tumors, malignant epithelial odontogenic tumors or odontogenic carcinomas are distinguished from the even rarer mesenchymal ones, the odontogenic sarcomas. The existence of odontogenic carcinosarcomas is not yet acknowledged by the World Health Organization. Odontogenic carcinomas comprise ameloblastic carcinoma (AmCa), primary intraosseous carcinoma (PIOC), clear cell odontogenic carcinoma, odontogenic ghost cell carcinoma (OGCC), and the special case of metastasizing ameloblastoma. Odontogenic sarcomas consist of ameloblastic fibrosarcoma and ameloblastic fibrodentinosarcoma and fibroodontosarcoma. Whereas metastasizing ameloblastoma can be diagnosed only after having metastasized, all other malignant odontogenic tumors present with atypia, increased cellularity and mitoses, and invasion. Odontogenic sarcomas are regarded as low-grade tumors that rarely metastasize. Odontogenic carcinomas, however, especially AmCa, OGCC, and PIOC, are more aggressive, with a 5-year survival rate of about 70% for AmCa and OGCC and a 3-year survival rate of about 37% for PIOC. Radical surgery, eventually in combination with radiotherapy, is the treatment of choice.

Clear cell odontogenic carcinoma: a diagnostic and therapeutic dilemma

BACKGROUND

Clear cell odontogenic carcinoma is a rare odontogenic tumor occurring in the anterior region of the mandible in 5th-7th decades and shows a female preponderance. It is potentially aggressive, capable of frequent recurrences and loco-regional and distant metastases.

CASE PRESENTATION

A 45-year-old woman presented with a radiolucent left mandibular swelling associated with loss of teeth. Left cervical lymph nodes were enlarged on palpation. The patient underwent resection of the tumor but consequent to resected margins being positive for tumor cells underwent left hemimandibulectomy with ipsilateral functional neck dissection and was free of recurrence at 8 months follow-up.

CONCLUSION

Clear cell odontogenic carcinoma should be considered in the differential diagnosis of jaw tumors with conspicuous clear cell component. Curettage or conservative resection inevitably results in recurrences and/or metastasis and more radical resection is warranted in these tumors, especially when they are large and show soft tissue invasion.

Clear cell odontogenic carcinoma: a comprehensive analysis of treatment strategies

BACKGROUND

Odontogenic neoplasms of predominately clear cells are unusual. They represent a diagnostic dilemma, and as a result, treatment strategies are diverse. Our goal is to present two new cases, summarize reported cases of clear cell odontogenic carcinoma (CCOC), assess potential risk factors for recurrence, and propose definitive surgical and therapeutic strategies.

METHODS

A literature search and analysis was performed. Regression models were used to predict risk factors for recurrence.

RESULTS

Forty-three cases of CCOC were reviewed, including two reported here. The overall rate of recurrent disease was 55%. Local recurrence rates were higher for curettage (80%) than for resection alone (43%). Age (p = .20), sex (p = .28), and tumor site (p = .50) did not predict risk for recurrence.

CONCLUSIONS

CCOC is a potentially aggressive tumor with a tendency for recurrence. Treatment strategies should be directed toward wide surgical resection with confirmation of tumor-free margins. Lymph node dissection and adjuvant radiation therapy should be considered in selected cases.

Clear cell odontogenic carcinoma and clear cell ameloblastoma: a single clinicopathologic entity? A new case and comparative analysis of the literature

BACKGROUND

Clear cell odontogenic carcinoma (CCOC) is histologically characterized by solid sheets and nests of clear cells. Clear cell ameloblastoma (CCAM) is histologically characterized by an ameloblastomatous component intermixed with an extensive clear cell component. In all literature reviews, no separation has been made between the clinicopathologic features of CCOC and CCAM.

PURPOSE

We sought to review and analyze the clinicopathologic and radiologic features and the biologic behavior of CCOC and to compare them with those of CCAM to evaluate the possible separation between the 2 lesions.

MATERIALS AND METHODS

A MEDLINE search of the English-language literature was carried out for CCOC and CCAM. Cases were classified according to their histologic features.

RESULTS

A total of 27 cases of CCOC (26 from the literature and 1 new case) and 8 cases of CCAM were found. CCOC patients showed a male-to-female ratio of 1:2.4, with a mean age of 59 years. CCAM patients showed a male-to-female ratio of 1.7:1, with a mean age of 44 years. CCOC and CCAM were predominantly found in the mandible. Both CCOC and CCAM showed a high rate of recurrence (50% and 63%, respectively) and metastases (33% and 25%, respectively). Several patients with CCOC presented with metastases at time of diagnosis, whereas patients with CCAM usually developed metastases only after several recurrences.

CONCLUSION

Based on the relatively small number of cases in the literature on CCOC and CCAM, it is difficult to confidently separate the 2 lesions. Both lesions should be considered low-grade malignancies and could well represent a clinicopathologic continuum of a single disease entity rather than 2 separate lesions.

Clear cell odontogenic carcinoma: evaluation of reported cases

PURPOSE

We present the cases of 4 patients with clear cell odontogenic carcinoma and a contrasting case of a patient with a calcifying epithelial odontogenic tumor from Massachusetts General Hospital. Differential diagnosis, distinguishing characteristics, and data from 32 cases in the literature are also reported. Because this rare tumor behaves aggressively with both regional and distant spread, a better understanding of its biologic behavior is imperative.

PATIENTS AND METHODS

The 4 patients with clear cell odontogenic carcinoma were women and had an average age of 65 years (range, 40 to 77 years). Three tumors were in the posterior mandible and 1 was in the maxilla. Three patients complained of pain; bony expansion and tooth mobility were noted in isolated cases. A comparison is made with other reported cases, and factors associated with recurrence and survival are presented.

RESULTS

All patients were treated with resection, and 1 patient received postoperative radiotherapy. Two patients with positive surgical margins underwent further resection. All patients have been followed an average of 2 years (range, 0.5 to 4 years) and presently have no evident disease.

CONCLUSIONS

Recognition of this unusual tumor and differentiating it from other clear cell neoplasms is critical in developing an appropriate treatment plan. Management should include wide en bloc resection and long-term follow-up.

Clear-cell variant of calcifying epithelial odontogenic tumor: clinical and radiographic characteristics

OBJECTIVES

Clear cells have been reported in approximately 8% of cases of calcifying epithelial odontogenic tumor (CEOT). The purpose of this study was to describe the clinical and radiographic features of clear-cell CEOT (CCEOT).

STUDY DESIGN

Eighteen cases of CCEOT were identified by review of the literature from 1958 to 2001, and a new one was added (total 19; 12 central, 7 peripheral).

RESULTS

Fourteen tumors (74%) were located in the mandible, with the central lesions favoring the posterior area and the peripheral lesions the anterior-bicuspid area. Radiographic features were as follows: 50% radiolucent, 50% mixed radiolucent-radiopaque; 92% unilocular; 64% well-defined noncorticated borders, 27% well-defined corticated borders, 9% irregular borders. Cortical perforation was common (67%) compared with CEOT without a clear-cell component (6.7%). Recurrence was reported in 17% of the central lesions and none of the peripheral ones.

CONCLUSIONS

CCEOT is a distinct variant of CEOT; its high tendency for cortical perforation may indicate a more aggressive behavior.

Metastasising clear cell odontogenic carcinoma: a case report and review of the literature

Primary odontogenic carcinomas are rare and examples which have metastasised are even more uncommon. We describe the first reported case of a clear cell odontogenic carcinoma which metastasised to distant bones, namely the 5th lumbar vertebra and hip, 3 years after initial diagnosis. The initial incisional biopsy was thought to represent a calcifying epithelial odontogenic tumour, but in the subsequent resection the tumour showed a prominent clear cell component admixed with squamous cells showing peripheral palisading, widespread infiltration and necrosis indicating a malignant neoplasm. Radiologically guided biopsy revealed a metastatic lesion in L5 vertebrae and left hip, confirmed by immunohistochemistry. The metastatic lesion had similar appearances to the first biopsy, and diagnosis was confirmed by comparison of histological features, immunohistochemistry and exclusion of a second primary lesion by clinical examination and imaging. The diagnosis of clear cell odontogenic carcinoma is a difficult one to make. The behaviour of these tumours is unpredictable. This case confirms that clear cell odontogenic carcinomas have the potential for distant metastasis and require long-term follow up.

Clear cell odontogenic carcinoma

Clear cell tumours, in the head and neck region, are usually derived from salivary or odontogenic tissues, or may be metastatic. A few clear cells may be present in odontogenic cysts, while, odontogenic neoplasms composed predominantly of clear cells are quite rare. They include calcifying epithelial odontogenic tumours (CEOT), ameloblastoma and odontogenic carcinoma. Clear cell odontogenic tumour (CCOT) has been classified in the last WHO classification as a benign tumour, but it is now recognized as a more sinister lesion and current opinion is that CCOT should be designated as a carcinoma. These tumours are characterized by aggressive growth, recurrences, and metastatic disease. A recent review of the literature has yielded 30 cases of tumours with similar characteristics. These tumours have a peak incidence in the 5th-7th decades, with a female predilection. The anterior portions of the jaws, especially the mandible, are most frequently affected. The aggressive potential of these neoplasms is well documented by the extensive invasion of adjacent tissues, multiple recurrences and regional or distant metastases.

Clear cell odontogenic carcinoma: a diagnostic dilemma

A 26-year-old man presented with a swelling in the right side of face and CT scan revealed a destructive tumor in the right maxilla. Tumor recurred within 5 years of its excision and histopathological examination revealed a clear cell odontogenic carcinoma. The rarity of this tumor, occurrence in maxilla and young age of the patient are some of the rare features which need documentation. The importance of its diagnosis and various differential diagnoses are discussed.

Clear cell odontogenic carcinoma: a clinicopathologic and immunocytochemical study of 5 cases

CONTEXT

Odontogenic tumor composed predominantly of clear cells is a rare neoplasm of the jaws that was initially designated as clear cell odontogenic tumor. Subsequent reports in the literature, however, all have indicated that this tumor exhibits an aggressive behavior characterized by infiltrative local growth, recurrence, or metastases.

OBJECTIVE

To ascertain the clinicomorphologic features and biologic behavior of this tumor group, we present 5 additional cases using the term clear cell odontogenic carcinoma.

DESIGN

Histologic and immunohistochemical examinations were performed on clear cell odontogenic carcinomas from 5 patients. Clinical and follow-up data were recorded, and the literature was reviewed.

RESULTS

The patients were 1 man and 4 women with an average age of 42.4 years at diagnosis. Three tumors occurred in the mandible and the other 2 in the maxilla. Four of the 5 cases occurred in the anterior or premolar areas of the jaws, appearing as poorly marginated radiolucencies. All cases consisted of islands and sheets of large clear cells and small basaloid cells with scanty eosinophilic cytoplasm, which were separated by thin, mature, fibrous septae. The tumors were unencapsulated and showed aggressive infiltration of the surrounding muscle and perineural tissues. Most of the clear cells contained cytoplasmic glycogen. Immunocytochemically, the tumor cells were positive for pan-keratin, cytokeratin 19, and epithelial membrane antigen, but were negative for vimentin, S100 protein, desmin, smooth muscle actin, human melanoma antigen (HMB-45), and alpha(1)-antichymotrypsin. Follow-up data showed 4 of 5 patients to have multiple local recurrences, and 1 of these 4 had submandibular lymph node metastasis and a fatal outcome due to uncontrollable tumor growth.

CONCLUSION

These results suggest that odontogenic clear cell neoplasms are at least low-grade malignancies and should be classified as carcinomas.

Clear cell odontogenic carcinoma. Report of two cases and review of the literature

This study reviews the literature and reports on the morphologic and immunophenotypic features of 2 clear cell odontogenic carcinomas occurring in the mandible of elderly women, showing extensive infiltration into adjacent tissues. The tumor cells were large, with clear cytoplasm, and arranged in irregular sheets. Some of the latter demonstrated a peripheral rim of cells with eosinophilic cytoplasm or included duct-like structures. There was no evidence of ameloblastic differentiation. Most cells contained glycogen granules and were immunoreactive for cytokeratins and epithelial membrane antigen. In the differential diagnosis other clear cell odontogenic, salivary gland, and metastatic tumors should be considered. Both cases were treated with surgical excision, and the patients are free of disease after 3 and 5 years, respectively. In the literature, however, variable behavior of these tumors has been reported, including recurrence and metastases. It is recommended that terms such as clear cell ameloblastoma and clear cell odontogenic tumor not be used to describe such tumors.

Radiographic manifestation of clear cell odontogenic tumor

Clear cell odontogenic tumors are uncommon, only 20 cases having been reported in the literature. We report a case that presented with unique radiographic manifestations over a period of 12 years; no similar case has been reported to date. Documentation of the malignant nature of the condition and of the range of clinical and radiographic manifestations with which this neoplasm can present provides useful insight into its pathogenesis and progression. Early and timely recognition of the lesion, histopathologic examination, and aggressive interventional procedures are in order to successfully treat this condition and prevent a potentially fatal outcome.

Central hyalinizing clear cell carcinoma of the mandible and the maxilla a clinicopathologic study of two cases with an analysis of the literature

We describe two cases of primary intraosseous hyalinizing clear cell carcinomas of the jaws. One tumor arose in the mandible, the other in the maxilla. Both patients were adult women. Histologically, both tumors were characterized by a population of clear, glycogen-rich cells arranged in solid nests, trabeculae, and occasional single files, surrounded by a markedly hyalinized fibrous stroma. In close admixture with the clear cells, a second component of smaller cells having eosinophilic cytoplasms was also noted. Focal areas of squamous metaplasia were seen in one of the tumors. Neither nuclear pleomorphism nor mitotic activity were conspicuous features. Mucicarmine stains were negative in both tumors. Immunohistochemically, the tumor cells expressed cytokeratins and epithelial membrane antigen. Stains for S100 protein, smooth muscle specific actin, and carcinoembryonic antigen were all negative. Both patients are alive and well 14 and 17 months respectively after the diagnosis without evidence of metastasis or recurrence. The major importance of recognizing the existence of this rare form of salivary gland-type adenocarcinoma arising as a primary lesion in the mandible or the maxilla lies in avoiding misdiagnosing it as other primary or metastatic clear cell neoplasms, including various odontogenic clear cell tumors, other primary intraosseous salivary gland tumors, and metastatic clear cell adenocarcinomas from other organs, particularly the kidney.

Clear cell odontogenic tumor in the mandible: report of a case with an immunohistochemical study of epithelial cell markers

A rare case of clear cell odontogenic tumor is presented with an immunohistochemical study using epithelial cell markers. A 35-year-old Japanese man was admitted with a complaint of painless swelling in the anterior region of his mandible. Radiological examination showed a relatively well-defined multilocular radiolucency with root resorption of the adjacent teeth. Despite a subtotal mandibulectomy, the tumor recurred three times. Histologically, the tumor was composed of proliferating clear cells and infiltrated through the cancellous bone. Histochemical and ultrastructural analyses detected cytoplasmic glycogen granules in the clear cells. They showed immunoreactivities for cytokeratin 8, 13 and 19, filaggrin and anti-ameloblastoma antibodies, suggesting an odontogenic epithelial origin.

Clear cell odontogenic carcinoma: A case report and literature review of odontogenic tumors with clear cells

Clear cell odontogenic carcinomas are uncommon epithelial neoplasms that have metastatic potential. We describe such a tumor in a 67-year-old Japanese man with a well-defined, unilocular radiolucent area in the mandible. The tumor was enucleated and has not recurred or metastasized 3 years after surgery. Histologically, the tumor was composed of a predominant clear cell area and a plexiform ameloblastic pattern. The latter was located at the periphery of the tumor. In the English literature, 19 cases of clear cell odontogenic carcinoma, clear cell odontogenic tumor, and clear cell ameloblastoma have been reported. The mean age of the patients at diagnosis was 56.4 years and the gender ratio (M:F) was 8:11. Fourteen tumors were located in the mandible and 5 in the maxilla. Recurrence or metastasis occurred in approximately one half of these patients, and five of the patients died of their disease. More than one half recurrent or metastatic tumors contained palisading clear cells.

Clear cell odontogenic tumour: a case with induction of dentin-like structures?

A case of clear cell odontogenic tumour, which occurred centrally in the mandible of a 56-year-old Japanese woman, is reported with its histochemical, immunohistochemical and ultrastructural findings. Histologically, the tumour nests were composed of large glycogen-rich clear cells and small non-clear polygonal cells and were separated by thin mature fibrous connective tissue septae. Immunohistochemically, both types of tumour cells showed positive expression of various cytokeratins, in particular cytokeratin 19, and of epithelial membrane antigen. Eosinophilic hyaline deposits and possible dentin-like structures were occasionally formed in contact with the epithelial nests and are regarded as indicative of the epithelial-mesenchymal inductive capacity of this tumour. The aggressive nature of the present tumour was assumed through its invasive growth pattern and occasional mitotic figures. Although it was diagnosed as clear cell odontogenic tumour according to the present WHO classification, the patient must be followed carefully because of its probable malignant nature.

Some current concepts on the pathology of ameloblastomas

This article describes some fundamental concepts and new developments in the pathologic characteristics of ameloblastoma. The former include (1) the necessity of separating ameloblastomas into three clinical types, namely the solid or multicystic (the classic intraosseous ameloblastoma), the unicystic, and peripheral varieties; (2) the importance of the tumor's location in the jaws; and (3) the manner in which cancellous and compact bone of the jaws affect the spread of ameloblastomas. New developments discussed include the desmoplastic ameloblastoma, the clear cell ameloblastoma, the recognition of the so-called acanthomatous epulis in dogs as a fairly common spontaneous animal model of ameloblastoma, and some work concerning therapeutic irradiation of ameloblastomas. Additional topics include the problems involved in the early microscopic diagnosis of ameloblastoma and of ameloblastic carcinoma and our lack of knowledge concerning the cause of ameloblastomas.

Clear cell odontogenic carcinoma in the mandible: histochemical and immunohistochemical observations with a review of the literature

A rare case of clear cell odontogenic carcinoma was investigated using histochemical and immunohistochemical methods. The tumor occurred in the anterior mandible of a 69-year-old Japanese man. Histologically, the tumor was composed mostly of large clear cells and squamous cells. Columnar-shaped cells with basophilic nuclei polarized away from the basement membrane were observed at the periphery of the tumor foci. The tumor cells had aggressively invaded muscle and perineural tissues. The tumor cells were positive for PAS staining. Immunohistochemically, tumor cells reacted positively to keratin, cytokeratin19, epithelial membrane antigen, and S-100 protein. The tumor was diagnosed as a clear cell odontogenic carcinoma. Its characteristics are discussed in term of its histopathological, histochemical and immunohistochemical features.

Clear-cell ameloblastoma (clear-cell odontogenic carcinoma): report of a case

Clear-cell ameloblastoma (clear-cell odontogenic carcinoma) is an uncommon odontogenic epithelial neoplasm. We report a case of a well-circumscribed 2 cm radiolucent lesion of the anterior mandible in a 30-year-old woman; this tumor was curetted. The first recurrence (at 5-year follow-up) was treated by aggressive curettage, and in the second recurrence a block resection was performed. However, 2 years after the resection was performed, the tumor recurred for a third time as an extraosseous gingival tumor, and 6 months later a recurrence was noted involving only alveolar mucosa.

Clear cell ameloblastoma or odontogenic carcinoma. A case report

An ameloblastoma of the right maxilla with a biphasic pattern of folicular ameloblastoma and clear cells, with an aggressive clinical behaviour in a 71-year-old male is reported. A literature review of clear cell ameloblastomas is made, focussing the discussion on the convenience of considering this type of ameloblastoma to be a low-grade odontogenic carcinoma.