Digital microscopy assessment of angiogenesis in different breast cancer compartments

Abstract

Background/aim: Tumour angiogenesis defined by microvessel density (MVD) is generally accepted as a prognostic factor in breast cancer. However, due to variability of measurement systems and cutoffs, it is questionable to date whether it contributes to predictive outline. Our study aims to grade vascular heterogeneity by comparing clear-cut compartments: tumour associated stroma (TAS), tumour parenchyma, and tumour invasive front.

Material and methods: Computerized vessel area measurement was performed using a tissue cytometry system (TissueFAXS) on slides originated from 50 patients with breast cancer. Vessels were marked using immunohistochemistry with CD34. Regions of interest were manually defined for each tumour compartment.

Results: Tumour invasive front vascular endothelia area was 2.15 times higher than that in tumour parenchyma and 4.61 times higher than that in TAS (P < 0.002). Worth to mention that the lymph node negative subgroup of patients show a slight but constant increase of vessel index in all examined compartments of breast tumour.

Conclusion: Whole slide digital examination and region of interest (ROI) analysis are a valuable tool in scoring angiogenesis markers and disclosing their prognostic capacity. Our study reveals compartments' variability of vessel density inside the tumour and highlights the propensity of invasive front to associate an active process of angiogenesis with potential implications in adjuvant therapy.

Figure 1

Selecting an ROI of tumour associated stroma (TAS) immunomarked with CD34-green circle, having at the same time an overview of the whole sample, and zoom in of ROI.

Figure 2

ROI of tumour (T) area stained with CD34, overview of whole sample, and zoom in target area.

Figure 3

Invasive front (IF) selection area stained with CD34, overview of whole sample, and zoom in marked area.

Figure 4

Average REA values for each of TAS, tumour parenchyma, and invasive front compartments of all patients.

Figure 5

TAS-REA, T-REA, and IF-REA for both N0 and N > N0 group of patients. N0 group developed slightly more vasculature in tumour and invasive front compartments when comparing with N > N0 group.