title: Tumor chemosensitivity and chemoresistance assays.
abstract: BACKGROUND
  Chemosensitivity and chemoresistance assays have been used to select potentially more effective chemotherapy regimens and to avoid the toxicity of potentially ineffective drugs.
  
  
  METHODS
  Literature review was conducted.
  
  
  RESULTS
  The relevant outcome measure for chemosensitivity assays is improved patient survival. However, the relevant outcome measure for chemoresistance assays is more controversial. Advocates propose that the avoidance of the toxicity of potentially ineffective drugs is the relevant outcome, whereas others believe that the latter is an intermediate outcome and that improved patient survival is the appropriate outcome for both chemoresistance and chemosensitivity assays. There have been no clinical trials showing that either of these assays is associated with improved patient survival.
  
  
  CONCLUSIONS
  In terms of improved patient survival, the clinical role of chemosensitivity and chemoresistance assays is unproven. The use of the assays will vary depending on the type and stage of the tumor involved, the proposed role of chemotherapy, and the role of the empiric judgement of the physician.
authors.affiliation: Technology Assessment and Clinical Guidelines, Aetna Health Plans, and Aetna Life and Casualty Company, Chicago, IL, USA.
authors.forename: E
authors.initials: E
authors.lastname: Brown
authors.forename: M
authors.initials: M
authors.lastname: Markman
mesh_terms: D017024:Chemotherapy, Adjuvant; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D016879:Salvage Therapy