Ameloblastic carcinoma arising from anterior skull base

Malignant transformation of primary ameloblastoma of skull: case report and review of current literature

Background

Since 1964, there has been a scarcity of reported cases of primary ameloblastoma (AM) or ameloblastic carcinoma (AMCa) of the skull. The clinical presentation and distinctive features of this uncommon condition at specific anatomical sites remain unclear. We report a case of malignant transformation of a primary AM of the skull situated in the frontal-temporal-parietal region and highlight its similarities to other cases reported in the literature.

Clinical presentation

A 53-year-old female patient presented with a 20-day history of headaches and bilateral lower limb weakness for 10 days. Physical examination revealed slow and unsteady gait. An occupying lesion was observed in the right frontal-temporal-parietal region of the skull on the Cranial imaging. A right cranial bone tumor margin expansion resection was performed. The patient's motor functions recovered normally after surgery. Postoperative imaging examinations showed10 tumor resection. Follow-up imaging examinations showed tumor recurrence. The patient underwent resection of the recurrent tumor. Postoperative pathological analysis revealed malignant transformation of the AM.Follow-up imaging examinations showed tumor recurrence again. The patient was admitted for stereotactic radiotherapy. Follow-up imaging examinations demonstrated no evidence of tumor recurrence and subsequent chest CT revealed no signs of metastasis.

Conclusion

Primary AM or AMCa of the skull is increasingly being described in the literature, but detailed reports on the malignant transformation of primary AM of the skull are lacking. The pathogenesis of this condition remains unclear. Aggressive treatment and close follow-up may be crucial for preventing disease recurrence and malignant transformation.

Rare solitary pituitary metastasis of maxillary ameloblastic carcinoma: illustrative case

BACKGROUND

Ameloblastic carcinoma (AC) is a rare odontogenic carcinoma with histological features resembling ameloblastoma. Metastasis to distant organs and direct expansion into the skull base structures are associated with a poor clinical outcome. This rare case of AC metastasis to the pituitary gland presented without local recurrence at the primary focus of the maxilla.

OBSERVATIONS

A 47-year-old man had a 2-year history of AC in the right maxilla. Computed tomography for his regular checkup incidentally demonstrated pituitary tumor, rapidly growing over 2 months. He presented with the recent onset of panhypopituitarism and visual field defect. Magnetic resonance imaging showed a large, irregularly shaped intrasellar and suprasellar lesion with chiasmal compression. Endoscopic endonasal transsphenoidal surgery was performed for decompression of the optic apparatus to avoid intracranial spread. Histopathology confirmed metastatic AC, and a genetic panel test confirmed BRAF V600E mutation. Stereotactic radiotherapy (SRT) with the CyberKnife system was administered to the residual tumor. Remarkable tumor shrinkage was obtained, and panhypopituitarism was resolved 12 months later.

LESSONS

A multidisciplinary treatment strategy including maximal safe resection to avoid dissemination in combination with SRT may be crucial for local control with the preservation of pituitary and visual functions in patients with solitary pituitary metastatic AC.

Rare Ameloblastic Carcinoma Metastasis to the Cervical Spine: A Case Report

BACKGROUND AND IMPORTANCE

Ameloblastic carcinoma (AC) is a malignant neoplasm of epithelial origin that typically arises from the mandible or maxilla. It represents approximately 2% of all odontogenic tumors. Gross total resection is the surgical goal given AC's aggressiveness and propensity for recurrence. We present the first reported AC metastasis to the cervical spine.

CLINICAL PRESENTATION

A 61-yr-old African American female with a history of AC of bilateral mandibles and lung metastases presented with neck pain and right arm weakness progressive over several months. Cervical spine imaging demonstrated a cervical 3 pathological fracture with severe anterior vertebral body compression and resultant cervical 2-3 kyphotic deformity and bony retropulsion causing severe cord compression. The patient underwent a cervical 3 corpectomy and cervical 2-4 anterior fixation followed by a cervical 3 laminectomy and cervical 2-5 dorsal internal fixation and fusion. Postoperatively, the patient's neurological exam remained stable and imaging showed improved spinal alignment and appropriate anterior and posterior instrumentation. Unfortunately, the patient thereafter suffered a decline in performance status and progression of lung metastatic disease. Her oncology team is considering chemotherapy and stereotactic radiosurgery, but her prognosis remains grim.

CONCLUSION

AC is a rare and aggressive pathology with a poor prognosis despite multimodal therapy. We present the first case of AC metastatic spread to the spine. We aim to bring this pathology to the attention of our worldwide neurosurgical colleagues and share our surgical approach and multidisciplinary management to assist those who may encounter this pathology in the future.

A Rare Presentation of Ameloblastic Carcinoma of the Sinus Cavity and Skull Base

Ameloblastic carcinoma (AC) is an exceedingly rare odontogenic cancer about which there is limited information in the literature. We present a case of AC originating in the sinus cavity and extending to the skull base in a patient in the first trimester of pregnancy. Diagnostic work up was complicated by this pregnancy, which delayed radiation exposure with imaging. Once scans were obtained, diagnosis was further complicated by the radiographic similarities between possible lung metastases and previously undiagnosed sarcoid nodules. After thorough work up to rule out metastatic disease, the patient was successfully treated with primary surgical resection followed by adjuvant chemoradiation. The patient remained disease free at one year after therapy. This case demonstrates the importance of thorough work up in the diagnosis of AC, and is an opportunity to review the literature and discuss therapeutic methods to treat this rare, aggressive neoplasm.

Reconnoitre ameloblastic carcinoma: A prognostic update

AIM

Malignant odontogenic tumor, ameloblastic carcinoma (AC) is challenging to study owing to its rarity, complexity and limited availability of literature. This further makes it difficult to establish its clinical characteristics and prognosis. Our study aimed to evaluate AC's clinico-demographic factors and their relation with prognosis and survival.

MATERIALS AND METHODS

Literature was systematically reviewed for cases pertaining to AC, starting from January 2000 to December 2016. All the required data was obtained, arranged and analysed using Cox regression ratio and Kaplan Meir survival analysis. From the database, 153 cases were retrieved as per the inclusion/exclusion criteria.

RESULTS

The results demonstrated that age of patient, mode of treatment and metastasis affects overall survival. The categorisation of AC as primary or secondary type does not have any role in determining prognosis.

CONCLUSION

Overall survival of AC patient depends upon age, site, treatment and metastasis. For a better prognosis early surgical management of the tumor appears to be the most favourable mode of treatment.

Usefulness of 11C-methionine positron emission tomography for detecting intracranial ameloblastic carcinoma: A case report

Ameloblastic carcinoma, secondary type, is an extremely rare odontogenic malignant tumor. The present study reports the case of a 58-year-old male with ameloblastic carcinoma that extended into the intracranial space close to the internal carotid artery. Surgical excision was performed, as headaches were being caused via compression by the mass. Small remnants of the tumor remained surrounding the internal carotid artery following surgical resection. Although the remnant tissue was not detected on magnetic resonance imaging or 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET), it was clearly visualized on ¹¹C-methionine PET in the early post-operative follow-up period. No neurological deficits were exhibited during the follow-up period, and ¹¹C-methionine PET was able to detect the remnant lesion distribution in the intracranial space. The current study presents a rare case of ameloblastic carcinoma that extended into the intracranial space. In addition, several diagnostic imaging tools were compared in order to determine the most suitable imaging modality. At present, the patient is continuing a therapeutic course of radiation and evident mass reduction has been observed. However, the therapeutic effects are currently under consideration. To the best of our knowledge, this is the first study on the effectiveness of using ¹¹C-methionine PET for detecting ameloblastic carcinoma with intracranial extension.

Ameloblastic carcinoma: A clinicopathologic dilemma - Report of two cases with total review of literature from 1984 to 2012

Ameloblastic carcinoma (AC) is a rare primary odontogenic tumor that has histological features of both ameloblastoma and carcinoma. A total number of 92 case reports speak about its rare incidence, affecting mostly the mandible as a locally destructive lesion. The maxilla is affected even more rarely as only 35 cases have been reported until 2012 in scientific literature. The clinical course of AC is generally aggressive, with extensive local bone destruction. The most common clinical features include swelling, pain, trismus, significant bone resorption with tooth mobility, dysphonia and intraoral fistula. We report two cases of AC with aggressive behavior.

Ameloblastic carcinoma: An analysis of 12 cases with a review of the literature

The diagnosis of ameloblastic carcinoma is often difficult and the optimal treatment methods remain controversial. The current study retrospectively investigated the optimal diagnosis and treatment methods of 12 ameloblastic carcinoma patients at the West China Hospital of Stomatology, Sichuan University (Chengdu, China), and 20 patients selected from the PubMed database, were reviewed. The clinical features, diagnosis and outcome of the different treatments were evaluated. Ameloblastic carcinoma occurred in 12 out of a total of 538 ameloblastoma patients; the majority were of the primary type. Of the 538 ameloblastoma patients, 294 were male, 244 were female with a male to female ratio of 1.2:1. The predilection age is 20–30 years, which accounts for 40% of the total. In total, 461 cases were in the mandible and 77 were located in the maxilla. The cure rate of the primary type and the recurrence rate of the secondary type tumors were higher in the patients from the West China Hospital of Stomatology compared with those reported in the literature. In particular, a case with a long-term survival of 30 years is presented, which is considered to be relatively rare. The evolution of the clinical course has experienced three stages: Ameloblastoma (1978) followed by metastatic ameloblastoma (2000) and finally ameloblastic carcinoma (2008). To avoid recurrence, wide local excision with postoperative radiation therapy is required. While novel therapeutic regimens should also be considered as appropriate, including carbon ion therapy and Gamma Knife stereotactic radiosurgery. However, controlled studies with larger groups of patients are required to increase the accuracy of results.

Ameloblastic carcinoma: Secondary dedifferentiated carcinoma of the mandible: Report of a rare entity with a brief review

Epithelial odontogenic tumors arise from odontogenic epithelial structures. Malignant epithelial odontogenic tumors are extremely rare. Ameloblastic carcinomas may present denovo, ex ameloblastoma or ex odontogenic cyst. Most ameloblastic carcinomas are presumed to present denovo. To date less than 45 cases of ameloblastoma with metastasis have been reported. It occurs primarily in the mandible in a wide range of age groups; no sex or race predilection has been noted. It may present as a cystic lesion with benign clinical features or as a large tissue mass with ulceration, significant bone resorption, and tooth mobility. The lesion is usually found unexpectedly after an incisional biopsy or the removal of a cyst. Histologic features of ameloblastic carcinoma shows tumor cells that resemble the cells seen in ameloblastoma, but they show cytologic atypia. Moreover, they lack the characteristic arrangement seen in ameloblastoma. The clinical course of ameloblastic carcinoma is typically aggressive, with extensive local destruction. Here we describe a rare case of ameloblastic carcinoma (secondary dedifferentiated carcinoma) of mandible in a 40-year-old female patient. Ameloblastic carcinoma: Secondary dedifferentiated carcinoma of the mandible.

Ameloblastic carcinoma of the maxilla: A case report

This study aims to present the clinical features and treatment of a case of maxillary ameloblastic carcinoma. Ameloblastic carcinoma is a rare malignant odontogenic carcinoma that has metastatic potential. Due to its rare incidence, there are few studies focusing on its radiological characteristics. When ameloblastic carcinoma demonstrates an aggressive appearance, it may be diagnosed as a malignant tumor; however, in cases showing a non-aggressive appearance, it is difficult to distinguish ameloblastic carcinoma from ameloblastoma. We report a case of ameloblastic carcinoma of the maxilla in a 59-year-old male patient, including the clinical signs, radiological images and pathological features. A partial area was surgically excised under local anesthesia and the material was sent to the Laboratory of Oral Pathology. The histological sections revealed a fragmented odontogenic tumor of epithelial origin, consisting of solid parenchyma and also revealed basal cells resembling ameloblasts, occasionally arranged in palisades. Certain parts of the architecture resembled that of an ameloblastoma; however, the cytology of other areas confirmed the diagnosis of ameloblastic carcinoma of the maxilla. The patient was scheduled for definitive surgery, including a right maxillectomy and radiotherapy. The patient was followed up every 3 months. After 2 years follow-up, there were no clinical or radiological signs of recurrence.

Ameloblastic carcinoma, secondary type: a case report

Malignant variants of ameloblastoma include metastasizing ameloblastoma, which microscopically appears benign but has metastasized and ameloblastic carcinoma that exhibits malignant histopathologic features. Ameloblastic carcinoma is classified into 2 types: a primary odontogenic malignancy and a secondary type resulting from malignant transformation of ameloblastoma. Most secondary ameloblastic carcinomas result from malignant transformation of a primary lesion after repeated postsurgical recurrences. Therefore it is rare to find an untreated secondary type presenting with histologic features of malignant transformation from an earlier benign lesion. We experienced a rare case of ameloblastic carcinoma, secondary type which might arise in an untreated ameloblastoma. The mechanism by which a preexisting benign ameloblastoma goes through a malignant transformation is also described.

Ameloblastic carcinoma

Ameloblastic carcinoma (AC) is a rare aggressive malignant epithelial odontogenic tumor of the maxillofacial skeleton with a distinct predilection in the mandible. It may appear de novo or originate from a pre-existing ameloblastoma or odontogenic cyst. It exhibits cytological features of ameloblastoma and carcinoma. It may present as a cystic lesion with benign clinical features or as a large tissue mass with ulceration, significant bone resorption and tooth mobility. The clinical course of ameloblastic carcinoma is typically aggressive, with extensive local destruction. Direct extension of the tumour, lymph node involvement and metastasis to various sites has been reported. Wide local excision is the treatment of choice. Regional lymph node dissection should be considered and performed selectively. Radiotherapy and chemotherapy have limited role in the treatment of ameloblastic carcinomas. Close periodic reassessment of the patient is mandatory.

Ameloblastic carcinoma: A case report and literature review

Ameloblastic carcinoma (AC) is a rare epithelial odontogenic tumor of the jaws, which exhibits cytological features of ameloblastoma and carcinoma. It has a distinct predilection for mandible. These lesions may initially show histologic features of ameloblastoma that dedifferentiate over time. Others may present with features of epithelial dedifferentiation in ameloblastoma. A case of ameloblastomic carcinoma in a 64-year-old male is reported, who presented with swelling in the left mandible 3 months after the extraction of the left upper molar.

Ameloblastic carcinoma of the mandible with metastasis to the skull and lung: advanced imaging appearance including computed tomography, magnetic resonance imaging and positron emission tomography computed tomography

Ameloblastic carcinoma is a very rare malignant odontogenic tumour with characteristic histopathological and clinical features, which requires aggressive surgical treatment and surveillance and, therefore, differs from ameloblastoma. Metastasis typically occurs in the lung. Only one patient with metastasis to the skull has previously been described and no prior case reports have presented MRI and positron emission tomography-CT (PET-CT) imaging findings. We describe a case of ameloblastic carcinoma with metastasis to the skull and lung with emphasis on imaging features including MRI and PET-CT.