Pulmonary metastatic disease in ameloblastoma

Pulmonary Malignant Ameloblastoma without Local Recurrence 31 Years after Primary Resection: A Case Report and Literature Review

A 78-year-old man with a history of surgical resection for ameloblastoma 31 years earlier visited our hospital for prolonged cough. Chest computed tomography showed multiple nodules in both lungs. Although there was no local recurrence in the mandible, the specimen taken from a transbronchoscopic bronchial biopsy showed recurrent ameloblastoma. Despite receiving no treatment, the disease in our patient remained clinically stable for 8.4 years. Chest physicians should be aware that pulmonary malignant ameloblastoma can first relapse several decades after curative surgery. In addition, pulmonary malignant ameloblastoma without local recurrence may be associated with a good prognosis.

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.

Metastasizing Ameloblastoma With Localized Interstitial Spread in the Lung: Report of Two Cases

Ameloblastoma is a locally aggressive, epithelial odontogenic tumor involving mandibles and maxillas. Distant metastasis is a very rare condition and is designated as metastasizing (malignant) ameloblastoma despite its benign histological appearance. Up to now, only 27 well-documented cases of metastasizing ameloblastomas are reported in the literature, and lung is the most commonly involved organ. In previous reports of pulmonary metastasizing ameloblastomas, there was little description of the histopathologic finding. Here, the authors report 2 cases of pulmonary metastasizing ameloblastomas with special emphasis on their interesting, interstitial spread along alveolar septa, resulting in a unique 2-cell pattern under microscopic examination. Pulmonary metastasizing ameloblastoma may pose difficulty in diagnosis if the pathologist is not aware of patient's clinical history of ameloblastoma.

Malignant ameloblastoma: concurrent presentation of primary and distant disease and review of the literature

Malignant ameloblastoma is a rare tumor of odontogenic origin with a metastatic focus. Distant metastatic disease is found most commonly in the lungs. A review of the literature shows that most cases of malignant ameloblastoma involve a disease-free period from primary tumor extirpation to the discovery of metastasis. This report describes the case of a 56-year-old man presenting with ameloblastoma of the maxilla and a solitary pulmonary metastasis concurrently. This represents a rare case in which there is a simultaneous diagnosis of primary ameloblastoma and a metastatic lesion. Appropriate workup for ameloblastoma includes surveillance for metastatic disease. Surgical resection of primary and distant disease is recommended. Chemotherapy and radiation may play a role in palliation when resection of metastatic disease is not feasible.

Hypercalcemia caused by metastatic adamantinoma: response to radiotherapy

Purpose. To describe successful palliation of a patient with metastatic adamantinoma presenting with lung metastases and hypercalcemia resulting from a parathormone-like substance released from the tumor.

Methods and materials. The records of a patient with a history of a tibial adamantinoma who presented with symptoms of hypercalcemia 20 years after the original surgery, as well as the literature concerning hypercalcemia and adamantinoma were reviewed and summarized.

Results. After thorough review of the literature we found no prior reports of radiation being used for palliation of hypercalcemia associated with metastatic adamantinoma.We report rapid improvement in symptoms and normalization of serum calcium levels following a course of radiation therapy. The patient remains asymptomatic 15 months following radiotherapy despite a gradual return of elevated serum calcium levels.

Discussion. Radiation therapy should be considered as a palliative option for patients who are not surgical candidates presenting with medically refractory hypercalcemia.

Ameloblastoma of the mandible with pulmonary metastases 45 years after initial diagnosis

Ameloblastoma of the mandible is a rare odontogenic tumour that rarely metastasizes. We report a patient with a slowly progressing ameloblastoma of the mandible diagnosed at the age of seven and resected multiple times due to tumour recurrence. Multiple pulmonary metastatic nodules were resected at thoracotomy 27 years after the initial diagnosis; however, further pulmonary disease was discovered. The patient was admitted with chest pain due to pulmonary metastases 45 years after the initial diagnosis. The metastases were intraluminal and could be attributed to tumour cell aspiration during the surgical procedures on the mandible. The patient also suffered from hypercalcaemia which was attributed to a parathormone-like substance secreted by the tumour.

Malignant ameloblastoma metastatic to the lungs 29 years after primary resection: a case report

We describe a case of a 55-year-old man presenting with a metastatic malignant ameloblastoma 29 years after the primary tumor was resected. This represents the longest period between initial diagnosis and first subsequent metastasis recorded as a case report. This case illustrates distinctions between the terms metastatic and malignant; it also highlights the difficulties derived from the accumulation of data by new diagnostic modalities (electron beam CT and positron emission tomography) and their integration into assessment algorithms.

Pulmonary metastasis of ameloblastoma: case report and review of the literature

Ameloblastomas are benign tumors of odontogenic epithelial origin. There is a high incidence of local recurrence associated with these tumors, and distant metastasis is rare. A review of the English literature shows that there have been 41 prior reports of pulmonary metastases from ameloblastomas of the oral cavity. We present another case of ameloblastoma metastatic to the lung and review the histopathology and mechanism of metastatic spread.

Aberrant gene expression in epithelial cells of mixed odontogenic tumors

Comparative investigations of odontogenic cells in normally forming teeth and tumors may provide insights into the mechanisms of the differentiation process. The present study is devoted to late phenotypic markers of ameloblast and odontoblast cells, i.e., proteins involved in biomineralization. The in situ expression of amelogenins, keratins, collagens type III and IV, vimentin, fibronectin, osteonectin, and osteocalcin was performed on normal and tumor odontogenic human cells. The pattern of protein expression showed some similarities between ameloblasts and odontoblasts present in normally developing human teeth and cells present in neoplastic tissues of ameloblastic fibroma, ameloblastic fibro-odontomas, and complex odontomas. Amelogenins (for ameloblasts) and osteocalcin (for odontoblasts) were detected in cells with well-organized enamel and dentin, respectively. In contrast, "mixed" cells located in epithelial zones of mixed odontogenic tumors co-expressed amelogenins and osteocalcin, as shown by immunostaining. The presence of osteocalcin transcripts was also demonstrated by in situ hybridization in these cells. Keratins and vimentin were detected in the same epithelial zones. Tumor epithelial cells were associated with various amounts of polymorphic matrix (amelogenin- and osteocalcin-immunoreactive), depending on the types of mixed tumors. No osteocalcin labeling was found in epithelial tumors. This study confirms that the differentiation of normal and tumor odontogenic cells is accompanied by the expression of some common molecules. Furthermore, the gene products present in normal mesenchymal cells were also shown in odontogenic tumor epithelium. These data may be related to a tumor-specific overexpression of the corresponding genes transcribed at an undetectable level during normal development and/or to an epithelial-mesenchymal transition proposed to occur during normal root formation. A plausible explanation for the results is that the odontogenic tumor epithelial cells are recapitulating genetic programs expressed during normal odontogenesis, but the tumor cells demonstrate abnormal expression patterns for these genes.