Purpose: Increased microvessel density (MVD), a reflection of tumor angiogenesis, is associated with diminished relapse-free and overall survival (OS) in several subsets of breast cancer patients. However, the utility of this assay in node-positive patients treated with adjuvant cyclophosphamide, doxorubicin, and fluorouracil (CAF) has not been well studied.
Patients and methods: Immunostaining for factor VIII-related antigen was performed on tissue sections from a subset of node-positive patients who received one of three dose/schedule regimens of CAF during participation in Cancer and Leukemia Group B protocol 8541. Sections from 577 cancers exhibited acceptable tumor and immunostaining quality and were included in the study. Each section was examined quantitatively for MVD as well as non-quantitatively by scoring the presence or absence of a prominent vascular pattern.
Results: MVD counts were not associated with relapse-free or OS in univariate analysis. The presence of a prominent plexiform vascular pattern was correlated with decreased OS (P =.0085) in univariate analysis, but this pattern was not an independent prognostic indicator of survival in multivariate analysis. No apparent clinically important interactions between measures of angiogenesis, other prognostic factors, administration of tamoxifen, and chemotherapy dose were observed.
Conclusion: Assessment of angiogenesis does not provide useful information regarding prognosis in node-positive breast cancer patients treated with adjuvant CAF, nor do these measures predict which patients will benefit from dose intensification or addition of tamoxifen.