No significant role for angiogenesis in nasal polyposis.
BACKGROUND
Nasal polyposis is a common disease of which little is currently known. Recent studies have shown up-regulation of several proangiogenic factors. The aim of this study was to assess and quantify how much angiogenesis occurs in nasal polyps and therefore whether angiogenesis is involved in the etiology of polyposis.


METHODS
Biopsy specimens of polyp tissue and inferior turbinate (IT) were taken from patients undergoing polypectomy and compared with IT samples from control patients. Five patients were used per study group. Biopsy specimens were either stained with a fluorescent lectin for confocal microscopy or snap frozen and sectioned for histology for the examination of multiple measures of angiogenesis.


RESULTS
No significant differences in capillary density, capillary-associated proliferation, capillary surface density, or capillary volume density were seen between the three study groups, and the regression of surface density versus volume density described a linear relationship. Polyp samples showed increases in capillary diameter and interstitial proliferation.


CONCLUSIONS
These results show no active angiogenesis occurring in the polyp or changes in capillary bed architecture, although capillaries seem more edematous in the polyp. As the capillary supply increases in line with the physiological needs of the growing polyp, we conclude that angiogenesis is not a driving force in the etiology of nasal polyposis.
Ahmed
Shahzada K
SK
Angiogenesis Research Group, Centre for Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom. s.ahmed@doctors.org.uk
Williams
James L
JL
Drake-Lee
Adrian
A
Egginton
Stuart
S
D001706:Biopsy; D002196:Capillaries / Q000473:pathology; D049109:Cell Proliferation; D018450:Disease Progression; D006801:Humans; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D009297:Nasal Mucosa / Q000098:blood supply*; D009298:Nasal Polyps / Q000473:pathology*; D009389:Neovascularization, Pathologic / Q000473:pathology*; D011379:Prognosis; D014420:Turbinates / Q000098:blood supply*