what does exit place mean?

http://www.breastcancer.org/treatment/radiation/types/ext/

Hi Icey ... Try the above link from this site.

It shows a picture of how the radiation beams travel across our body.  In my case, there were two different fields.  My left breast was treated.  The beams traveled from upper right down across the left and lower left up across the right.  There is an exact location for the beams.  This is called your radiation prescription.  The exact location of the beams are figured by a physicist and programmed into the machine. 

My rad onc showed me how the beams will travel.  I used Aquafor, Benadryl lotion and Aloevera on the radiated breast. 

Best of luck to you,

Bren

If you are having whole breast fields only, then the radiation beam exits on the other side of the breast.  Exit points are not an issue in that case, although the field may cover more area than you expect especially under the arm . 

The issue of exit points comes with treatment of nodal (e.g. supraclavicular or internal mammary) fields or perhaps chest wall (post-mastectomy) fields.

It is a good idea to ask the rad onc exactly what areas you should cover with lotion.