title: Ameloblastoma with varied sites of metastasis: report of two cases and literature review.
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, #79 Qingchun Road, Hangzhou 310003, Zhejiang, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, #79 Qingchun Road, Hangzhou 310003, Zhejiang, PR China. Electronic address: lydabao@126.com.
authors.forename: Jian-feng
authors.initials: JF
authors.lastname: He
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, #79 Qingchun Road, Hangzhou 310003, Zhejiang, PR China.
authors.forename: Zhi-yong
authors.initials: ZY
authors.lastname: Li
authors.affiliation: Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, #79 Qingchun Road, Hangzhou 310003, Zhejiang, PR China.
authors.forename: Jian-hua
authors.initials: JH
authors.lastname: Liu
mesh_terms: D000328:Adult; D000564:Ameloblastoma / Q000473:pathology / Q000556:secondary*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D061705:Image-Guided Biopsy / Q000379:methods; D008175:Lung Neoplasms / Q000556:secondary*; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008441:Maxillary Neoplasms / Q000473:pathology*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D015641:Radiography, Interventional / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Ameloblastoma; Histopathology; Metastases