The prognostic value of angiogenesis by Chalkley counting in a confirmatory study design on 836 breast cancer patients

This study addresses the prognostic value of estimating angiogenesis by Cha lkley counting in breast cancer. A population-based group consisting of 836 patients with operated primary, unilateral invasive breast carcinomas was included from a predefined region and period of time. The median follow-up time was 11 years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. The Chalkley count was obtained by a 2 5-point grid within three, subjectively selected, vascular tumor areas of h ighest microvessel density. The Chalkley count was analyzed in three catego ries using predefined Chalkley cutoff points at five and seven. There were significant correlations between high Chalkley counts and axillary lymph no de metastasis, large tumor size, high histological malignancy grade, and hi stological type. A high Chalkley count showed lower probabilities of recurr ence-free survival (P < 0.0001) and overall survival (P < 0.0001), In the C ox multivariate analysis, the hazard ratio (and 95% confidence interval) sh owed that the increased risk to die were: 1.55 (1.19-2.03) with Chalkley co unts between 5 and 7; 2.26 (1.72-2.98) with counts greater than or equal to 7 compared with counts less than or equal to 5; and 1.46 (1.14-1.87) with counts greater than or equal to 7 compared with counts between 5-7, The stu dy confirmed that estimation of angiogenesis by Chalkley counting had indep endent prognostic value in breast cancer patients. The Chalkley count could be useful to stratify node-negative patients for adjuvant treatment.