title: Diagnosis, workup, and prognosis of cutaneous metastases of unknown primary origin.
abstract: BACKGROUND
  Metastatic cancer of unknown primary (MCUP) accounts for 5-10% of presenting oncology patients. Premorbid identification of the primary source occurs in only 20-25% of cases. A small fraction of these tumors present in the skin and are thus likely to be encountered by dermatologists and dermatologic surgeons.
  
  
  OBJECTIVE
  To present a practical schema for the diagnosis and evaluation of patients with MCUP.
  
  
  METHODS
  Case report and literature review.
  
  
  CONCLUSIONS
  The diagnosis of MCUP is associated with a poor prognosis, with median survival rates of less than 1 year. Efforts to identify subgroups of patients with understanding of these subgroups will enable early identification of patients with treatable disease and more favorable prognoses.
authors.affiliation: Department of Dermatology and Dermatologic Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Carroll
authors.forename: Matthew
authors.initials: M
authors.lastname: Fleming
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Chitambar
authors.forename: Marcy
authors.initials: M
authors.lastname: Neuburg
mesh_terms: D005260:Female; D006801:Humans; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary; D011379:Prognosis; D012878:Skin Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000556:secondary*