TUMOR ANGIOGENESIS AND RECTAL-CARCINOMA

PURPOSE: This study was designed to determine whether those rectal can cers that demonstrated increased vessel ingrowth or angiogenesis behav e in a different fashion. METHODS: The paraffin blocks of 48 rectal ca ncers removed by low anterior or abdominoperineal resection were recal led and immunostained with a monoclonal antibody specific for endothel ial cell Factor VIII. The intense reddish brown color imparted to bloo d vessels facilitated their quantification which was undertaken at x10 0 and x200 magnification. Vessel counts within three microscopic field s were averaged and the relationships between angiogenesis score and t umor size, depth of invasion, incidence of lymph node or distant metas tases, and survival were assessed. RESULTS: Significantly higher angio genesis scores were seen in tumors with transmural penetration (at X10 0, P = 0.002; at X200, P = 0.002) and in patients dying before five ye ars (at x100, P = 0.013; at x200, P = 0.034). Although higher angiogen esis scores were seen in patients with larger tumors and metastases, t hese trends were not statistically significant. CONCLUSIONS: Our resul ts suggest that the growth of rectal cancer is dependent on the ingrow th of new blood vessels, and that increased vascularity promotes disse mination and adversely affects survival.