Malignant degeneration of a residual radicular cyst]

The degeneration risk is extremely low for odontogenic cysts. The present communication deals with a squamous cell carcinoma of the left maxilla. Clinically, it showed all the symptoms of an infected cyst; but histologically, it presented carcinomatous degeneration on certain parts of the cystic epithelium. It was a true cystocarcinoma.     

Carcinoma arising from reduced enamel epithelium

Intra-osseous squamous cell carcinomas are considered to be derived from odontogenic epithelium. Except for an associated benign odontogenic tumor or a cyst, evidence for an odontogenic origin is only circumstantial. In a 73-year-old male, an intra-osseous squamous cell carcinoma in the mandible could be shown to have originated from reduced enamel epithelium. There were no histological features substantiating the odontogenic origin, other than the continuity of tumor epithelium with reduced enamel epithelium surrounding the crown of an impacted molar tooth. Thus, it is concluded that the odontogenic derivation of an intra-osseous squamous cell carcinoma in the jaw cannot be inferred from specific histological features, but should be based on the exclusion of an oral cavity lining epithelial origin. Still more proof is the demonstration of continuity of the carcinoma with odontogenic epithelium, be it normal, cyst lining or benign odontogenic tumor.     

Carcinoma arising from reduced enamel epithelium

Intra-osseous squamous cell carcinomas are considered to be derived from odontogenic epithelium. Except for an associated benign odontogenic tumor or a cyst, evidence for an odontogenic origin is only circumstantial. In a 73-year-old male, an intra-osseous squamous cell carcinoma in the mandible could be shown to have originated from reduced enamel epithelium. There were no histological features substantiating the odontogenic origin, other than the continuity of tumor epithelium with reduced enamel epithelium surrounding the crown of an impacted molar tooth. Thus, it is concluded that the odontogenic derivation of an intra-osseous squamous cell carcinoma in the jaw cannot be inferred from specific histological features, but should be based on the exclusion of an oral cavity lining epithelial origin. Still more proof is the demonstration of continuity of the carcinoma with odontogenic epithelium, be it normal, cyst lining or benign odontogenic tumor.     

Central odontogenic fibroma. A report of two controversial cases illustrating diagnostic dilemmas

Two unusual cases of central odontogenic fibroma are described and used to illustrate differential diagnostic problems in this controversial group of lesions. The first case had a cystic lesion noted on routine radiography in the left ramus of the mandible. This particular case was unusual histologically as it showed in addition to typical areas of odontogenic fibroma a small inflamed cyst lined by epithelium containing many hyaline bodies. The second case presented with anaesthesia of the right lower lip and an enlarged chin prominence. The lesion was diagnosed as an odontogenic fibroma but with a somewhat unusual histological appearance in that there were abundant areas of osseous metaplasia throughout the lesion.     

Primary intraosseous carcinoma of the mandible with probable origin in an odontogenic cyst

Primary intraosseous carcinoma of the jaws (PIOC) is an uncommon lesion, but may not be as rare as commonly believed. Since the putative source of the epithelium giving rise to an intraosseous carcinoma is the epithelium involved in odontogenesis, these lesions are often designated as odontogenic carcinomas. These tumors may theoretically arise (1) from the lining of odontogenic cysts, (2) from other epithelial odontogenic tumors, or (3) de novo from presumed odontogenic rests. While not included in most classifications of PIOC, it appears logical to also include intraosseous mucoepidermoid carcinomas as a fourth type of PIOC. A case of primary intraosseous squamous cell carcinoma of the mandible, with evidence of origin in an odontogenic cyst, is presented. The recent literature on carcinomas arising in jaw cysts is reviewed.     

Entstehung eines Plattenepithelkarzinoms auf dem Boden einer odontogenen Zyste

Malignant change in the epithelium of an odontogenic cyst and growth of an invasive squamous cell carcinoma is rare. The diagnosis of malignant disease is mostly only established by histological evaluation of excised tissue because the initial clinical appearance does not differ much from that of odontogenic cysts. The clinical course of one patient after removal of an impacted canine and adjacent cystic tissue is presented. Histological evaluation of the specimen led to diagnosis of a squamous cell carcinoma arising from the cystic epithelium. Partial resection of the maxilla was performed subsequently and 1 year postoperatively the patient was free from recurrence or metastasis. This case report underlines the importance of submitting any soft tissue excised in the treatment of odontogenic cysts to histologic evaluation.     

Neoplastic potential of odontogenic cysts

Odontogenic cysts and tumors are distinct entities and quite a common occurrence in the jaw bones. The lining of odontogenic cysts shows a potential for neoplastic transformation to non odontogenic malignancies like squamous cell carcinoma and mucoepidermoid carcinoma, and odontogenic tumors like ameloblastoma and adenoamatoid odontogenic tumor (AOT). AOT is a benign, epithelial odontogenic tumor, common site being the anterior maxilla. Its origin from a dentigerous cyst and in the mandible is rare. A case of an AOT arising from a dentigerous cyst associated with an impacted permanent mandibular left lateral incisor is reported.     

A primordial cyst without keratinization in the maxillary molar region: a case report

In this article we report a case of a 54-year-old man with a primordial cyst in the left maxillary molar region. We performed conventional radiographs and computed tomography (CT) without contrast enhancement, but it was difficult to determine whether the lesion was a tumor or a cyst. CT images with contrast medium showed a cyst, not a tumor. Histopathologically, the cyst wall was composed of fibrous connective tissue lined by nonkeratinized squamous epithelium. Based on its clinical, radiological, and histopathological findings, this lesion was diagnosed as a primordial cyst. This case indicated that enhanced CT imaging is useful for differentiating between cysts and benign tumors and that there are no specific differences in the radiological appearance between primordial cysts and odontogenic keratocysts     

Primary intraosseous carcinoma of the jaws arising from an odontogenic cyst--a case report.

BACKGROUND: Squamous cell carcinoma of the jaw located purely in the bone is extremely rare. Most of these intraosseous carcinomas, also called odontogenic carcinomas are thought to arise from the epithelial lining of an odontogenic cyst. CASE REPORT: A primary intraosseous carcinoma arising from an odontogenic cyst in a 64-year-old woman is reported. No subjective symptoms were noted by the patient. Multiple retained teeth with associated presumed cystic lesions were evident in the lower jaw on a routine radiograph. Histology revealed an intraosseous carcinoma after removal of the teeth and "cystectomy". No metastasis was detected. Segmental resection of the mandible, selective neck dissection and reconstruction with an iliac bone graft was performed. The patient is free of disease after 3 years. CONCLUSION: Although primary intraosseous carcinoma is rare, this case emphasizes the importance of careful histological examination of apparently innocuous odontogenic cysts. In addition, as malignant changes in their epithelial lining are always possible, "cystic" lesions should not only be removed but as completely as possible.     

Calcifying odontogenic cyst

Summary The calcifying odontogenic cyst designated by Gorlin et al. in 1962 is a cystic lesion of the odontogenic origin which is characterized histologically by keratinizing ghost cell and its calcification. Recently, neoplastic potential of this lesion has been pointed out by several investigators and this lesion has been considered to be a borderline lesion between cyst and tumor. From the view point of neoplastic potential of this lesion, we evaluated 8 cases of calcifying odontogenic cyst encountered in our hospital within 12 years from 1972 to 1984. Our cases were divided into two types, cystic and proliferative. Clinical differential diagnoses of the cystic type were globulomaxillary cyst, primordial cyst and cystic odontoma, while those of the proliferative type were ameloblastoma and calcifying epithelial odontogenic tumor. There wre 2 cases of the proliferative type among all the cases. One of them was recurrent lesion with 20 years' duration. We agreed to the designation of “calcifying ghost cell odontogenic tumor”, proposed by Fejerscov and Krogh, rather than calcifying odontogenic cyst. Furthermore, we propose to sub-classify it into cystic type and proliferative type.     

Glandular odontogenic cyst of the mandible: from incidental radiographic discovery to prosthetic reconstruction

A large multilocular radiolucent lesion involving the anterior mandible was noted incidentally in a 44-year-old woman who sought routine dental treatment. An incisional biopsy revealed that this lesion represented an uncommon developmental odontogenic cyst known as a glandular odontogenic cyst. The lesion was removed surgically, followed by reconstruction with a right anterior iliac crest bone graft. This article reviews the radiographic, clinical, and histopathologic appearance of this rare odontogenic cyst, as well as the surgical management and the patient's subsequent prosthetic rehabilitation.     

A large glandular odontogenic cyst of the mandible: report of case

Glandular odontogenic cyst (GOC) is generally considered uncommon, but several investigators claim there is a more frequent occurrence than previously thought. However these case reports lacked confirming data to validate their claim. On the other hand, it is possible that cases of central mucepidermoid carcinoma or later periodontal cyst might be viewed as glandular odontogenic cyst. This is a report of a case of a 70-year old male who presented with a firm swelling in the right side of his edentulous mandible. Radiographic examination revealed a multilocular radiolucent lesion in the mandible extending from the right first premolar to the left second premolar and reaching the inferior mandible. Clinical findings, the health history, and microscopic examination of excised tissue confirmed the diagnosis of GOC. The lesion was excised and post-operative healing was uneventful.     

Glandular odontogenic cyst: Report of a case with cytokeratin expression

The glandular odontogenic cyst is a rare lesion that was recognized as a distinct entity in the latest WHO typing of odontogenic tumors. We report a glandular odontogenic cyst that recurred after surgical removal from the anterior mandible of a 54-year-old white man. Immunohistochemical study showed that the cystic epithelium reacted positively to antibodies directed against cytokeratins (CKs) 7, 13, 14, and 19 and negatively to CKs 8 and 18.     

Case report of a pigmented dentigerous cyst and a review of the literature on pigmented odontogenic cysts

This paper reports the first case of a dentigerous cyst containing melanin-pigment and melanocytes in the lining epithelium, and the first case of a odontogenic cyst with macroscopically visible pigmentation in the cyst wall. The patient was a 29-year-old Japanese male with a cystic lesion in the left retromolar area of the mandible. Pathologic examination revealed the lesion to be a dentigerous cyst with or without mild surface keratinization, and numerous granules of melanin-pigment were distributed in the basal cells of the epithelial lining. Furthermore, dendritic melanocytes were scattered in the basal layer. Review of the literature revealed that pigmented odontogenic cysts are uncommon, and only 11 cases have been documented; eight were odontogenic keratocyst, one was a gingival cyst, one was a botryoid odontogenic cyst, and one was a lateral periodontal cyst. The possible origin of melanocytes in odontogenic lesions is discussed.     

Intra-osseous squamous cell carcinoma of the maxilla: probably arisen from non-odontogenic epithelium.

This paper reports a case of intra-osseous squamous cell carcinoma (IOSC) of the maxilla. The patient was a 52-year-old male with a chief complaint of swelling of his hard palate. The lesion was initially diagnosed as an incisive canal cyst from the clinical and radiographic findings, but histological examination revealed the lesion to be a poorly differentiated squamous cell carcinoma. The review of the literature yielded only a few previous cases of IOSC of the maxilla, which were probably of odontogenic origin. The present maxillary IOSC is thought to be non-odontogenic in origin.     

Glanduläre odontogene Zyste des Unterkiefers

Background

Glandular odontogenic cyst (GOC) is a rare lesion of both, the maxilla and mandible, leading to extensive osteolysis. Histologically, it shows thin layers of squamous and cylindrical cells, lined with mucinous metaplasia. This makes it difficult to differentiate from a mucoepidermoid carcinoma. The recurrence rate is high.

Case report

During a routine X-ray examination we saw massive osteolysis of the whole mandible in a 30-year-old female. All teeth were vital. The biopsy taken showed a benign cyst although the clinical aspect was similar to an ameloblastoma. The cyst was removed after intravital fixation with Carnoy’s solution. The bony cavity was left without filling material. Uneventful bony healing occurred.

Discussion

Due to rare occurrence and similarity to botryoid odontogenic cyst and low-grade mucoepidermoid carcinoma GOC is difficult to identify. It remains without clinical signs for years and is identified in routine X-rays in most cases. We recommend cystectomy after use of Carnoy’s solution for intravital fixation. No filling material is required for complete bony healing.     

Malignant cyst of the lateral aspect of the neck: branchial cleft carcinoma or metastasis?

A 58-year-old man had a left jugulodigastric mass, which was found to be cystic by computed tomography, and no evidence of other lesions. Grossly and histologically, the surgical specimen consisted of a thin-walled, fluid-filled cyst lined by squamous epithelium that varied in appearance from benign to invasive squamous cell carcinoma. The findings supported a differential diagnosis of branchial cleft carcinoma (BCCA) versus cystic growth of a lymph node metastasis from an occult malignancy. On this basis, guided biopsies of the upper aerodigestive tract were performed, with strong suspicion of a tonsillar bed lesion. Microscopic examination revealed the primary tumor within tissue excised from the left tonsillar fossa. Comparison of the current case with cases of BCCA and cystic tonsillar metastases from the literature illustrated the potential pitfalls in rendering a diagnosis of BCCA. Recognition of this lesion as a distinctive clinical variant of oropharyngeal carcinoma is warranted.     

Primary intraosseous odontogenic carcinoma arising in an odontogenic cyst or de novo: a clinicopathologic study of six new cases

The term primary intraosseous odontogenic carcinoma (PIOC) has been primarily used to describe a squamous cell carcinoma within the jaws arising either from a previous odontogenic cyst or de novo. Here, we report 6 new cases of PIOC, affecting 4 female and 2 male patients with a mean age of 56.2 years. Two cases involved the maxilla and 4 cases occurred in the mandible. The typical radiographic presentation was that of a radiolucent lesion with well or ill defined margins. Histopathologically, 4 cases were diagnosed as well differentiated keratinizing PIOC arising from previous odontogenic cysts (2 odontogenic keratocysts and 2 periapical cysts). The remaining 2 cases were poorly differentiated nonkeratinizing PIOC, which appeared to arise de novo. Treatment consisted of surgical removal, with postoperative radiotherapy in 5 cases, and to date neither recurrence nor metastasis have occurred. Knowledge of the clinical, radiographic, and histopathologic features of PIOC allows accurate diagnosis and appropriate treatment of this rare malignancy.     

Central odontogenic fibroma of mandible: a case report and review of the literature

Central odontogenic fibroma is an extremely rare benign tumor, accounting for less than 0.1% of all odontogenic tumors. The most recent literature review revealed that only 69 cases have so far been reported in the English literature, and only 1 of these cases showed radiologic appearance of a dentigerous cyst and this involved impacted maxillary incisors. A case of central odontogenic fibroma occurring in the mandible of a 30-year old female with radiological appearance of a dentigerous cyst involving an impacted lower first molar, presented here, appears to be the first reported case of central odontogenic fibroma of mandible with radiological appearance of dentigerous cyst in the English-language literature.     

Ameloblastic carcinoma of the mandible resembling odontogenic cyst in a panoramic radiograph

Ameloblastic carcinoma is a rare odontogenic tumor exhibiting histologic evidence of malignancy in the primary or recurrent tumor, regardless of whether it has metastasized or not. Most ameloblastic carcinomas are presumed to have arisen de novo, with few cases of malignant transformation of ameloblastoma being apparent. A case is reported of a 21-year-old caucasian female with ameloblastic carcinoma in the left angulus area of the mandible resembling an odontogenic cyst in the panoramic radiograph. In addition to the panoramic radiograph, computerized tomography (CT) and magnetic resonance (MR) images were taken preoperatively. This report demonstrates that CT or MR examinations may be crucial in differentiating odontogenic tumors from cysts.