Clear Cell Odontogenic Carcinoma: A Series of Three Cases

Abstract

Background: Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic epithelial neoplasm of the jaws. It is composed of irregular nests of clear to faintly eosinophilic cells resembling clear cell rests of primitive dental lamina and an intermixed hyalinized fibrous stroma. Most cases occur in the 5th and 6th decades of life, with a female predominance. The mandible is affected more than the maxilla. Clinical features vary from asymptomatic to non-specific pain, ill-defined radiolucency, root resorption, and sometimes soft tissue extension. Histology varies from bland to high grade. CCOC demonstrated a significant tendency to recur. Metastasis typically involves regional lymph nodes, which haves been reported in 20–25% of cases. Pulmonary metastasis rarely occurs. Differential diagnoses are broad and include odontogenic, salivary, melanocytic, and metastatic neoplasia. CCOCs are positive for cytokeratins, mainly AE1/AE3 and CK19. Most cases show EWSR1 rearrangement and rarely, the BRAFV600E mutation. Design: Patient charts were reviewed at our institution. A total of three cases were found in electronic medical records, which were diagnosed as clear cell odontogenic carcinoma over a period of six years (2014–2019). Patient charts were reviewed for medical history and radiology data. The pathology slides were reviewed by one or more faculty members. Results: We present three cases of CCOC, ranging in age from 40 to 69 years (two women and one man). Two cases involved the maxilla and one involved the mandible. Two presented with painful swelling and one with mass recurrence. Radiography results show that two had poorly defined radiolucent lesions, and one was heterogeneous with a small nodule projecting into the maxillary sinus. Histological examination revealed an epithelial neoplasm composed of irregular sheets, cords, and nests of polygonal cells with central hyperchromatic, mildly pleomorphic nuclei surrounded by clear to pale eosinophilic cytoplasm, with occasional mitotic figures. The tumor had infiltrated the bone and soft tissues. Two cases were immunopositive for CK5/6 and one case was positive for p63 and CK19. Interestingly, the eosinophilic dentinoid matrix interspersed among tumor cells in one case was consistent with its odontogenic origin. Histochemical staining showed PAS-positive and diastase-labile intracytoplasmic material consistent with glycogen. Conclusion: Our study highlights the potential diagnostic significance of dentinoid (although reportedly seen in only 7% of cases), along with CK5/6 immunopositivity, in supporting the histologic diagnosis of CCOC among a variety of neoplasia in its differential diagnosis.

Odontogenic carcinoma with dentinoid: case report and literature review of a rare entity

“…Of the nine primary lesions with imaging examination results, all appeared as well-defined radiolucencies, and eight contained variable amounts of mineralized material; seven lesions were described as unilocular and two as multilocular. All four recurrent lesions with available radiographic examination appeared as radiolucent lesions, three of which were with ill-defined margins [ 1 , 3 , 4 , 19 , 20 ]. Surgery was the primary therapeutic approach in all cases, including conservative (simple excisions, curettages, and enucleations) or radical (partial and segmental resections) modalities.…”

“…Surgery was the primary therapeutic approach in all cases, including conservative (simple excisions, curettages, and enucleations) or radical (partial and segmental resections) modalities. Two patients underwent neck dissection at the time of recurrent tumor resection, which did not show any evidence of regional lymphatic metastasis [ 1 , 19 ]. Postoperative radiotherapy and chemotherapy was performed in one patient [ 3 , 4 ], and adjuvant radiotherapy was performed in another patient [ 19 ]; in the latter case, the authors considered OCD to be synonymous with CCOC with dentinoid [ 19 ].…”

“…Two patients underwent neck dissection at the time of recurrent tumor resection, which did not show any evidence of regional lymphatic metastasis [ 1 , 19 ]. Postoperative radiotherapy and chemotherapy was performed in one patient [ 3 , 4 ], and adjuvant radiotherapy was performed in another patient [ 19 ]; in the latter case, the authors considered OCD to be synonymous with CCOC with dentinoid [ 19 ]. Follow-up information was available in 10 of 11 patients, however, the follow-up time of nine patients was shorter than 5 years.…”

“…Follow-up information was available in 10 of 11 patients, however, the follow-up time of nine patients was shorter than 5 years. Recurrence was recorded in six patients, all of which were initially treated with conservative surgical methods [ 1 – 4 , 19 , 20 ]. No regional or distant metastases were found in any patient [ 1 – 4 , 17 – 20 ].…”

“…Overall, our literature survey disclosed nine cases that met our study criteria for OCD (Table 1) [1][2][3][4][17][18][19].…”