title: Microregional fluctuations in perfusion within human tumours detected using laser Doppler flowmetry.
abstract: OBJECTIVE
  Transient fluctations in erythrocyte flux consistent with perfusion driven hypoxia have been previously reported using experimental tumour models. The present study was designed to establish whether such changes are a common feature of human tumours.
  
  
  METHODS
  A multi-channel laser Doppler system was used to monitor microregional changes in flow in human tumours. Eight individual tumours were investigated, two primary and one locally recurrent breast carcinoma, two metastatic skin deposits and three metastatic lymph nodes. Six custom designed microprobes (diameter of 300 microns), each monitoring a nominal sampling volume of approximately 10(-2) mm3 were inserted into the tumour and perfusion monitored over a period of 60 min.
  
  
  RESULTS
  The results show that in 54% of the regions monitored there was a change in microregional blood flow by a factor of 1.5 or more. Over the whole 60-min period, 19% of the changes were reversed, with a time course of 4-44 min.
  
  
  CONCLUSIONS
  This finding demonstrates that microregional fluctuations in perfusion occur frequently in human tumours. Furthermore, the observation that 19% of the changes were reversed implies that at least some of the cells are subject to transient acute hypoxia.
authors.affiliation: Mount Vernon Centre for Cancer Treatment, Mount Vernon Hospital and Tumour Microcirculation Group, Gray Laboratory, Middlesex, UK.
authors.forename: K H
authors.initials: KH
authors.lastname: Pigott
authors.forename: S A
authors.initials: SA
authors.lastname: Hill
authors.forename: D J
authors.initials: DJ
authors.lastname: Chaplin
authors.forename: M I
authors.initials: MI
authors.lastname: Saunders
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D001943:Breast Neoplasms / Q000098:blood supply*; D015687:Cell Hypoxia; D004912:Erythrocytes / Q000502:physiology; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry / Q000295:instrumentation; D008207:Lymphatic Metastasis; D008297:Male; D012039:Regional Blood Flow / Q000502:physiology; D012878:Skin Neoplasms / Q000098:blood supply* / Q000556:secondary; D013997:Time Factors