Oral and Maxillofacial Pathology Lung metastasis of ameloblastoma Background.—Ameloblastoma is found in 1% of all cysts and tumors of the jaws and is usually considered a benign lesion. However, it often exhibits locally aggressive behavior and tends to recur locally in 50% to 72% of cases. When metastases occur, which is rare, some of the lesions are then considered malignant. Ameloblastoma was discovered incidentally in a patient with no symptoms relative to the tumor. Case Report.—Woman, 27, had no history of habitual drinking or smoking but had undergone chest radiographs as part of a routine check-up for a job. She had a solitary pulmonary nodule in the right lung confirmed by computed tomography (CT) scan. The 2-cm well-defined lesion showed no calcification. Her history revealed buccal and lingual expansion of the posterior mandible in the second molar region at age 19 years. Radiographs suggested ameloblastoma, and an incisional biopsy confirmed a plexiform-type ameloblastoma, for which she underwent a hemimandibulectomy. The margins were free of tumor. Reconstruction of the mandibular body was completed. Based on her history and the current findings, search was made for a primary tumor, considering this solitary nodule a metastatic tumor. No primary tumor was found, but a partial pulmonary lobectomy was performed. Histopathologic analysis confirmed that the lesion was a metastatic ameloblastoma. The lesion was well-differentiated and characterized by peripheral columnar cells in peripheral palisading orientation. There were several areas filled by cells with clear, poorly defined cytoplasm with a central area of loosely arranged cells. An inflammatory
infiltrate filled with mononuclear cells was dispersed among collagen fibers. The lesion’s features were consistent with those found in the original jaw ameloblastoma. No further lesions have developed in the past 2 years either in the mandible or the lungs. Discussion.—The metastasizing ameloblastoma in this patient was discovered incidentally during a job-related physical examination. Usually pulmonary metastases do not respond well to treatment, so the best option is surgical removal. Patients who have ameloblastoma should be followed regularly to permit early detection of any asymptomatic lung metastases.
Clinical Significance.—Though typically benign and rarely metastasizing, this case of surgically treated ameloblastoma underscores the need of maintaining contact and monitoring, even with patients where complications are unlikely. If not for a routine employment examination, this case might have ended less favorably.
Senra GS, Pereira AC, dos Santos LM, et al: Malignant ameloblastoma metastasis to the lung: A case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 105:e42-e46, 2008 Reprints available from GS Senra, Faculdade de Odontologia de Sa˜o Jose´ dos Campos – UNESP, Dept de Biocieˆncias e Diagno´stico Bucal, Av Engenheiro Francisco Jose´ Longo, 777, 12245-000 – Sa˜o Jose´ dos Campos, SP; e-mail:
[email protected]
Oral and Maxillofacial Surgery Drain to relieve discomfort from third molar surgery Background.—Significant morbidity is associated with third molar surgery, including pain, trismus, and swelling. Minimizing or relieving these conditions has not been obtained without producing other adverse effects. Various types of drains have been used with the suture procedure after the surgical removal of impacted third molars and some success has been achieved. The pain, swelling, and trismus occurring after surgically removing impacted lower
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Dental Abstracts
third molars with and without Penrose drain placement were investigated. Methods.—Forty men and 60 women aged 18 to 40 years underwent surgical extraction of impacted lower third molars. They were randomly assigned to have a Penrose rubber drain inserted into the extraction socket near the buccal fold after surgery (experimental group) or have no