The immunohistochemical assessment of hypoxia, vascularity and proliferation in bladder carcinoma.
OBJECTIVE
Hypoxia and proliferation are important determinants of radiation responsiveness; prospective measures of these before radiotherapy may enable individualisation of treatment schedules. Immunohistochemical techniques offer a potential means of achieving this in routine biopsy material.


METHODS
Cellular hypoxia as measured by pimonidazole fixation and immunohistochemistry has been evaluated in a series of human bladder cancers with dual staining of sections for pimonidazole and either the vascular markers, CD31/34, or proliferation markers, Ki-67 or cyclin A. Twenty one tumour specimens were examined suitable for the double staining technique.


RESULTS
The median hypoxic fraction was 9% (range 0-38). Seven tumours did not stain for pimonidazole and 11 exhibited necrosis. The mean vascular density ranged from 16.7 to 160.6 vessels per mm2. The median hot spot count was 30 (range 16-43). There was a statistically significant increase in vessel density in hypoxic compared to oxic regions measured by both vessel density (P = 0.02) and hot spot count (P = 0.004). Proliferation indices decreased from oxic to hypoxic areas close to blood vessels.


CONCLUSIONS
We have demonstrated that bladder cancer exhibits a range of hypoxia, proliferation and vascular density which may be used to form the basis for patient selection for hypoxia modification, accelerated radiotherapy and vascular targeting agents.
Hoskin
Peter J
PJ
CR UK Tumour Biology and Radiation Therapy Group, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, Middlesex HA6 2RN, UK.
Sibtain
Amen
A
Daley
Frances M
FM
Saunders
Michele I
MI
Wilson
George D
GD
D018952:Antigens, CD34 / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D002295:Carcinoma, Transitional Cell / Q000098:blood supply / Q000737:chemistry* / Q000473:pathology*; D015687:Cell Hypoxia; D049109:Cell Proliferation; D019925:Cyclin A / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D009593:Nitroimidazoles / Q000032:analysis; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D011838:Radiation-Sensitizing Agents / Q000032:analysis; D013194:Staining and Labeling / Q000379:methods; D001749:Urinary Bladder Neoplasms / Q000098:blood supply / Q000737:chemistry* / Q000473:pathology*
D018952:Antigens, CD34; D014408:Biomarkers, Tumor; D019925:Cyclin A; D019394:Ki-67 Antigen; D009593:Nitroimidazoles; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D011838:Radiation-Sensitizing Agents; C033815:pimonidazole