title: Squamous cell carcinoma of lung with unusual site of metastasis.
abstract: BACKGROUND
  Lung cancer ranks among the most common and most lethal malignancies worldwide. Once vascular or lymphatic invasions occur, metastatic dissemination to distant sites is common. Bone, liver, adrenals, and brain are the most frequent sites of the distant disease. In this study we present a case of squamous cell carcinoma of lung with metastasis of the left knee bursa.
  
  
  METHODS
  A smoker man presented with cough and hemoptysis and squamous cell carcinoma of lung was diagnosed. Fourteen months later he developed pain and swelling of left knee. The biopsy and pathologic examination of the left knee bursa showed involvement of the bursa.
  
  
  CONCLUSIONS
  Squamous cell carcinoma of lung can metastasize in the unusual sites of the body.
authors.affiliation: Department of Internal Medicine, Ayatollah Rouhani Hospital, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Vakili
authors.affiliation: Department of Internal Medicine, Ayatollah Rouhani Hospital, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Behnaz
authors.initials: B
authors.lastname: Yousefghahari
authors.affiliation: Department of Pathology, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Sharbatdaran
keywords: Knee bursa; Lung; Metastasis; Squamous cell carcinoma