title: Monitoring substrate uptake and distribution by tumors using percutaneous catheters and solid nuclear track detectors.
abstract: OBJECTIVE
  This study was designed to test a new technique for measuring intratumoral drug and substrate concentrations using a modified percutaneous catheter and solid nuclear track detectors.
  
  
  METHODS
  A nephrostomy catheter was modified to allow exposure of the lumen of the catheter to adjacent tissue and placed percutaneously in a 4047 colon cancer growing in the flank of a Fischer 344 rat. Measurement of metabolite distribution was obtained using carbon-14-labeled deoxy-d-glucose and multiple strips of CR-39 (a solid nuclear track detector) placed sequentially in the catheter to measure the low energy beta emissions from the carbon-14.
  
  
  RESULTS
  The administered deoxy-d-glucose initially distributed to the vascularized rim of the tumor, but rapidly defused down concentration gradients into the necrotic core.
  
  
  CONCLUSIONS
  The preliminary data suggest that this technique is feasible. Further validation studies may show that this technique may allow for monitoring of temporal and spatial variations in the distribution of drugs and metabolites within tumors.
authors.affiliation: Department of Diagnostic Imaging, Temple University Hospital, Philadelphia, Pennsylvania 19140.
authors.forename: R A
authors.initials: RA
authors.lastname: Gatenby
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D002404:Catheterization; D003110:Colonic Neoplasms / Q000378:metabolism*; D005947:Glucose / Q000493:pharmacokinetics*; D009368:Neoplasm Transplantation; D011092:Polyethylene Glycols; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D002250:Carbon Radioisotopes; C028827:CR 39; D011092:Polyethylene Glycols; D005947:Glucose