Pulmonary metastases from an Ameloblastoma: Case report and review of the literature

Treatment efficacy and prognosis of pulmonary metastasizing ameloblastoma: a systematic review

The aim of this review was to integrate the current literature into a comprehensive evaluation of pulmonary metastasizing ameloblastoma (MA). Related articles, published since January 2000, were reviewed. The PubMed, Embase, Cochrane Database of Systematic Reviews, and Web of Science databases were searched based on the PRISMA guidelines. Twenty-four studies, including 28 case reports, met the eligibility criteria. The mean ± standard deviation disease-free interval after primary treatment was 12.1 ± 9.3 years. Adjuvant therapy (surgery and chemoradiotherapy) is considered appropriate for pulmonary MA patients presenting with rapid progression or apparent pulmonary symptoms. The proportion of patients undergoing simple follow-up (observation) has increased rapidly in the past 10 years. Meanwhile, among the three treatment groups (observation, surgery, and adjuvant therapy), no significant difference was found in the efficacy (P = 0.081) or progression-free survival (P = 0.263). The 5-year and 10-year overall survival rates were 72.4% and 52.8%, respectively. This study provides insights that could help surgeons with the management of patients presenting with pulmonary MA.

Ameloblastoma: clinical presentation, multidisciplinary management and outcome

We studied 21 patients who underwent radical ameloblastoma excision followed by immediate reconstruction. Comorbidities, consumption of alcohol and/or tobacco and BMI status did not contribute to an unfavorable outcome. Giant ameloblastoma (≥5 cm) and/or tumor involving bony curvatures increased surgical complexity, the incidence of complications and hospital stay.

Metastasizing Ameloblastoma: A 10 Year Clinicopathological Review with an Insight Into Pathogenesis

Ameloblastoma, a benign but locally aggressive odontogenic tumor, often demonstrates metastasis despite benign histological features and this variant is termed as metastasizing ameloblastoma (METAM). It was classified under the malignant category in the 2005 WHO but has been re-classified under benign epithelial odontogenic tumors in the latest 2017 WHO classification. The present review aimed at gathering the available data on METAM to update the current cognizance about the pathology. Comprehensive search of the databases (viz., PubMed, Medline, SCOPUS, Web of Science, EMBASE and Google Scholar) was done for published articles on METAM following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 42 cases were extracted. The mean age of occurrence was 42.71 ± 15.87 years. A slight male predilection was noted. Mandibular cases showed more metastasis than maxillary cases. Follicular ameloblastoma was most frequently encountered at secondary site followed by plexiform type. Lungs were the most commonly affected secondary sites. METAM is a rare odontogenic tumor and the diagnosis is usually made in retrospect. Inadequate treatment may result in multiple recurrences and metastasis in rare instances. Metastasis in ameloblastoma appears to be multi-factorial in nature and needs further investigation in untapped territory like exploration of quantum effects at cellular and molecular levels.

Pulmonary resection for multiple lung metastasis from ameloblastoma: a rare case report and literature review

INTRODUCTION

Ameloblastoma is a benign odontogenic epithelial neoplasm. Lung metastasis of ameloblastoma is extremely rare, and its biological behavior is still largely unknown. There is no consensus regarding the best method to treat metastasizing ameloblastoma.

CASE PRESENTATION

This report documents a 37-year-old female patient with multiple incidental bilateral pulmonary nodules on computed tomography (CT) and a medical history of ameloblastoma of the left mandible. On admission, her physical examinations and laboratory examinations were unremarkable. The patient underwent partial lobectomy of the middle right and lower right lung nodules via video-assisted thoracoscopic surgery, and the pathological diagnosis was confirmed as 'metastasizing ameloblastoma.' No adjuvant therapy was administered, and no evidence of progression was observed at the 12-month follow-up.

CONCLUSION

This is a rare case with multiple lung metastasis from ameloblastoma who was successfully treated with multiple pulmonary resections. The present study indicated that surgery may be considered an appropriate choice for lung metastasis of ameloblastoma.

An Ameloblastoma in the Middle Ear

An ameloblastoma is a locally aggressive odontogenic tumour that commonly develops from the odontogenic epithelium within the jawbone. Here we present for the first time a case of a rare primary ameloblastoma in the middle ear cavity, along with some consideration of its treatment and a new classification. A 65-year-old woman presented with a left middle ear cavity tumour. Pathological examination led to the diagnosis of an ameloblastoma. We resected the tumour along with an extensive part of the middle ear mucosa, which made it difficult to have an adequate margin. It is recommended that the remaining bone be ground 2-3 mm beyond the visible margin after resecting the gross tumour. Therefore, several cases are treated with conservative surgery, including physicochemical treatment. This factor should be considered when designing treatment strategies as good alternatives in cases where resection with an adequate margin is difficult.

A Conservative Approach to a Peripheral Ameloblastoma

Peripheral Ameloblastoma (PA) is the rarest variant of ameloblastoma. It differs from the other subtypes of ameloblastoma in its localization: it arises in the soft tissues of the oral cavity coating the tooth bearing bones. Generally, it manifests nonaggressive behavior and it can be treated with complete removal by local conservative excision. In this study we report a case of PA of the maxilla in a 78-year-old female patient and we describe the four different histopathological patterns revealed by histological examination. After local excision and diagnosis, we planned a long term follow-up: in one year no recurrence had been reported. The choice of treatment is illustrated in Discussion.

Distant metastasis from oral cancer: A review and molecular biologic aspects

Oral squamous cell carcinoma (OSCC) has been estimated to be the sixth most common cancer worldwide. The distant metastasis plays a critical role in the management and prognosis in oral cancer patients. Regarding the distant metastasis from the oral cancer, the hypopharynx is the most common primary site, followed by the base of tongue and anterior tongue. The present review article analyzes the characteristics of the distant metastases from the oral cavity from 1937 to 2015.

Ameloblastoma Phenotypes Reflected in Distinct Transcriptome Profiles

Ameloblastoma is a locally invasive benign neoplasm derived from odontogenic epithelium and presents with diverse phenotypes yet to be characterized molecularly. High recurrence rates of 50–80% with conservative treatment in some sub-types warrants radical surgical resections resulting in high morbidity. The objective of the study was to characterize the transcriptome of ameloblastoma and identify relevant genes and molecular pathways using normal odontogenic tissue (human “dentome”) for comparison. Laser capture microdissection was used to obtain neoplastic epithelial tissue from 17 tumors which were examined using the Agilent 44 k whole genome microarray. Ameloblastoma separated into 2 distinct molecular clusters that were associated with pre-secretory ameloblast and odontoblast. Within the pre-secretory cluster, 9/10 of samples were of the follicular type while 6/7 of the samples in the odontoblast cluster were of the plexiform type (p < 0.05). Common pathways altered in both clusters included cell-cycle regulation, inflammatory and MAPkinase pathways, specifically known cancer-driving genes such as TP53 and members of the MAPkinase pathways. The pre-secretory ameloblast cluster exhibited higher activation of inflammatory pathways while the odontoblast cluster showed greater disturbances in transcription regulators. Our results are suggestive of underlying inter-tumor molecular heterogeneity of ameloblastoma sub-types and have implications for the use of tailored treatment.

Ameloblastoma: 25 Year Experience at a Single Institution

Ameloblastoma is a rare, locally aggressive odontogenic neoplasm, accounting for fewer than 1 % of head and neck tumors. Recent literature suggests that the initial surgical approach and histologic growth patterns are the most important prognostic determinants in ameloblastoma. The aim of this study was to compare the clinical presentation, management, and outcomes of patients with ameloblastoma with data reported in the literature; the study spanned 2 decades at a single institution. The institution's database was searched for all patients with pathologically confirmed ameloblastoma, diagnosed between 1990 and 2015. The data collected included sex, age, clinical and imaging findings, management, histologic pattern, clearance of surgical margins, length of follow-up, time to recurrence, and disease-related mortality. The potential risk factors of recurrence were evaluated using log-rank test, proportional hazard model, and Fisher exact test. Review of the database yielded 54 patients with pathologically confirmed ameloblastoma and follow-up. Recurrence was noted in 13 (24 %) patients. Surgical approach was associated with the risk of recurrence (6.1 % following radical resection vs. 52 % following limited surgery, p = 0.002). There were trends toward higher recurrence rate in the group with pathologically documented positive margins (p = 0.054) and in follicular ameloblastoma (p = 0.35). Transformation into ameloblastic carcinoma was identified in two patients. There was no disease-related mortality. Our study confirms the recent data regarding the importance of radical surgical resection in management of ameloblastoma. Surgical approach appears to be the strongest predictor of tumor clearance.

Establishing the natural history and growth rate of ameloblastoma with implications for management: systematic review and meta-analysis

Background

Ameloblastoma is the second most common odontogenic tumor, known to be slow-growing, persistent, and locally aggressive. Recent data suggests that ameloblastoma is best treated with wide resection and adequate margins. Following primary excision, bony reconstruction is often necessary for a functional and aesthetically satisfactory outcome, making early diagnosis paramount. Despite earlier diagnosis potentially limiting the extent of resection and reconstruction, an understanding of the growth rate and natural history of ameloblastoma has been notably lacking from the literature.

Method

A systematic review of the literature was conducted by reviewing relevant articles from PubMed and Web of Science databases. Each article’s level of evidence was formally appraised according to the Centre of Evidence Based Medicine (CEBM), with data from each utilized in a meta-analysis of growth rates for ameloblastoma.

Results

Literature regarding the natural history of ameloblastoma is limited since the tumor is immediately acted upon at its initial detection, unless the patient voluntarily refuses a surgical intervention. From the limited data, it is derived that the highest estimated growth rate is associated with solid, multicystic type and the lowest rate with peripheral ameloblastomas. After meta-analysis, the calculated mean specific grow rate is 87.84% per year.

Conclusion

The growth rate of ameloblastoma has been demonstrated, offering prognostic and management information, particularly in cases where a delay in management is envisaged.

Multiple organ metastases from ameloblastoma detected by FDG PET/CT imaging

A 74-year-old patient was admitted to our hospital with recurrent ameloblastoma of the right mandible. Multiple lung nodules were noted during the presurgical evaluation. FDG PET/CT was subsequently performed to assess the nature of the nodules and search the possible primary tumors. The images showed abnormal FDG activity not only in the lung nodules but also in the lumbar vertebral body and the liver. Pathologic examination after hepatic biopsy demonstrated metastases from ameloblastoma.

Metastatic pulmonary ameloblastoma misdiagnosed as primary squamous cell carcinoma preoperatively

Ameloblastomas are rare odontogenic epithelial tumors that occur mainly in the mandible. Despite their benign histologic appearance, they are locally aggressive with a high recurrence rate. However, a metastasizing ameloblastoma has been rarely reported. According to the current World Health Organization classification system, the definitive diagnosis of metastasizing ameloblastoma can only be carried out in retrospect, after the event of metastasis. This case report describes a patient with metastatic pulmonary ameloblastoma, 17 years after the surgical excision of an odontogenic tumor, preoperatively misdiagnosed as primary squamous cell carcinoma.

Primary treatment of mandibular ameloblastoma with segmental resection and free fibula reconstruction: achieving satisfactory outcomes with low implant-prosthetic rehabilitation uptake

Ameloblastoma is a locally aggressive and disfiguring oral cavity tumour and surgical management is the mainstay of treatment. The ideal management of ameloblastoma should minimise recurrence, restore function and appearance and present minimal donor site morbidity. Conservative management is associated with minimal downtime but high recurrence rates. By contrast, segmental mandibulectomy with appropriate margins have much lower recurrence rates but presents the challenge of reconstruction. Osseointegrated (OI) implants and permanent dental prosthesis, while ideal, are not always available. We conducted a retrospective review on 30 consecutive patients at our centre with unicystic and multicystic ameloblastoma who were treated with segmental mandibular resection and free fibula flap reconstruction. Only three patients underwent OI implant insertion, with 40% of the patients not receiving any form of dental rehabilitation. We performed a functional and aesthetic outcome survey to determine patient satisfaction with this form of treatment. At an average follow-up of 5 years, there were no recurrences of tumour in our population. Of the 26 patients who responded to the survey, 96% of the patients reported that they were satisfied with their appearance, 88% reported an absolutely normal diet and 93% of the patients reported no problems with donor site function. Overall, we found that low uptake of dental rehabilitation did not adversely affect patient satisfaction and outcomes.

Ameloblastoma with varied sites of metastasis: report of two cases and literature review

OBJECTIVE

We report two rare cases of lung metastasis from maxillary ameloblastoma, in order to review its risk and analyse the types of metastases that can present with this disease.

METHODS

A 40-year-old male with multiple recurrences and a 46-year-old female, who had undergone successful surgical treatment of a maxillary ameloblastoma, presented with metastatic lesions. The primary tumour and metastases were benign in both patients. We reviewed and analysed 20 cases of the same condition reported in recent years.

RESULTS

Our initial treatment for the primary maxillary lesion was performed more than 10 years before the pulmonary lesions presented. Due to the aggressive nature of this tumour, metastases in the lungs and cervical lymph nodes (male patient) were confirmed.

CONCLUSION

These cases presented a diagnostic challenge due to the multiple and varied sites of recurrence, which indicate the natural behaviour of this tumour. Different routes of metastasis can occur, including implanting, haematogenous, and lymphatic spread. CT-guided percutaneous transthoracic lung biopsy is an important method to confirm metastatic ameloblastoma.