title: Ultrasound-enhanced drug delivery for cancer.
abstract: BACKGROUND
  Ultrasound, which has traditionally been used as a diagnostic tool, is increasingly being used in non-invasive therapy and drug delivery.
  
  
  METHODS
  Of particular interest to this review is the rapidly accumulating evidence that ultrasound may have a key role to play both in improving the targeting and the efficacy of drug delivery for cancer. Currently available ultrasound-triggerable vehicles are first described, with particular reference to the ultrasonic mechanism that can activate release and the suitability of the size range of the vehicle used for drug delivery. Further mechanical and thermal effects of ultrasound that can enhance extravasation and drug distribution following release are then critically reviewed.
  
  
  CONCLUSIONS
  Acoustic cavitation is found to play a potentially key role both in achieving targeted drug release and enhanced extravasation at modest pressure amplitudes and acoustic energies, whilst simultaneously enabling real-time monitoring of the drug delivery process. The next challenge in ultrasound-enhanced drug delivery will thus be to develop a new generation of drug-carrying nanoparticles which are of the right size range for delivery to tumours, yet still capable of achieving initiation of cavitation activity and drug release at modest acoustic pressures and energies that have no safety implications for the patient.
authors.affiliation: University of Oxford, Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, Oxford, OX3 7DQ, UK.
authors.forename: Steven
authors.initials: S
authors.lastname: Mo
authors.forename: Constantin-C
authors.initials: CC
authors.lastname: Coussios
authors.forename: Len
authors.initials: L
authors.lastname: Seymour
authors.forename: Robert
authors.initials: R
authors.lastname: Carlisle
mesh_terms: D000162:Acoustics; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D019220:High-Energy Shock Waves; D006801:Humans; D053758:Nanoparticles; D009369:Neoplasms / Q000188:drug therapy*; D004364:Pharmaceutical Preparations; D014464:Ultrasonic Therapy / Q000379:methods*
chemical_list: D000970:Antineoplastic Agents; D004364:Pharmaceutical Preparations