Fig. 1.

The identification of VM in invasive breast cancer specimens. (A) and (B) CD31-negative, PAS-positive vascular-like channels with or without red blood cells formed by breast cancer cells were counted as positive for VM (black arrow). Typical blood vessels were CD31-positive (red arrow). (C) and (D) Breast cancer without VM showed that a PAS-positive matrix is mainly present in the mesenchyme of the breast cancer tissue (white arrow) and has a close relationship with blood vessels (black arrow).