title: Mandibular metastasis in a patient with undiscovered synchronous thyroid and prostate cancer: A diagnostic dilemma.
abstract: BACKGROUND
  Mandibular metastasis as the first manifestation of undiscovered synchronous double primary cancers is extremely rare, so, it is presented in the current study.
  
  
  METHODS
  This study reports a 73-year-old man, complaining of a painful mass in the mandible. After history taking, physical examination and panoramic radiographic evaluation; an incisional biopsy was performed intraorally. Histological studies revealed a metastatic tumor of epithelial origin with nonspecific primary site. During metastatic workup of the patient, it was accidentally found that three organs including prostate, lung and thyroid were involved with cancer. Using immunohistochemical study (prostate-specific antigen (PSA), thyroid transcription factor 1 (TTF-1) and thyroglobulin), a final diagnosis of thyroid carcinoma metastasis to the mandible was established.
  
  
  CONCLUSIONS
  This case report showed that the practitioners should always maintain a high index of suspicion to the possibility that a patient with an orofacial metastatic lesion may have two or more synchronous primary cancers.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Zandi
authors.affiliation: Department of Pathology, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Jafari
authors.affiliation: Department of Oral and Maxillofacial Surgery, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Mona
authors.initials: M
authors.lastname: Isapour
authors.affiliation: Private Practice, Oral and Maxillofacial Radiologist, Hamedan, Iran.
authors.forename: Amir Abbas
authors.initials: AA
authors.lastname: Jafari
keywords: Mandible; metastasis; synchronous; thyroid carcinoma