title: Metastatic renal cell carcinoma involving the rectum.
abstract: OBJECTIVE
  Metastatic spread of a distant tumor to the rectum is extremely rare. To our knowledge, there have been no published reports of hematogenic metastasis from a renal cell carcinoma to the rectum.
  
  
  METHODS
  A patient with a renal cell carcinoma was initially treated by a radical right nephrectomy.
  
  
  RESULTS
  Nine months after the surgery he started to have multiple episodes of hematochezia. Colonoscopy showed a nodular lesion located in the distal rectum, and biopsy revealed an undifferentiated carcinoma. The patient then underwent abdominoperineal resection of the rectum, and histological examination showed metastatic renal clear cell carcinoma.
  
  
  CONCLUSIONS
  This case represents an exceedingly rare condition, which has never been reported before.
authors.affiliation: Departments of Coloproctological Surgery, Pathology, and Oncology, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Mário A
authors.initials: MA
authors.lastname: Rosito
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Damin
authors.forename: Anderson R
authors.initials: AR
authors.lastname: Lazzaron
authors.forename: Cartell
authors.initials: C
authors.lastname: André
authors.forename: Gilberto
authors.initials: G
authors.lastname: Schwartsmann
mesh_terms: D002292:Carcinoma, Renal Cell / Q000556:secondary*; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012004:Rectal Neoplasms / Q000556:secondary*; D014057:Tomography, X-Ray Computed