When tumors fuse with blood vessels, clumps of breast cancer cells can spread
Tests with fake vessels suggest this is an early step in metastasis
![breast cancer cells](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2017/12/120817_TS_cancer_feat.jpg?fit=860%2C460&ssl=1)
BREAKING AWAY Breast cancer cells (shown growing in a lab dish) move through the body in clusters. New research may shed light on how the clusters enter the bloodstream.
Tom Misteli, Karen Meaburn/NCI Center for Cancer Research