how can you get cancer cells in pass your lung border ????

Question: how can you get cancer cells in pass your lung border ????
- Keywords:
  cancer,
  cell,
  respiration
Asked by daisyfreeman1 to Arthur on 14 Nov 2014.
- Arthur Dyer answered on 14 Nov 2014:
  
  Hi there 🙂
  
  So I put viruses into people not cancer but the problem with cancer is that when it grows it can get so big that it pushes its way through into our blood stream when it is growing.
  
  One or two of the cancer cells might get knocked off by the movement of blood and these are then loose in our blood until they stick somewhere else (normally the place where the blood vessels are really thin which is the lungs!) and then they grow again and push through the walls of the blood vessels and into the lung

Question: how can you get cancer cells in pass your lung border ????