VARIABLE=result of sed?

I want to extract header part and sed it and put into $HEAD.
So I wrote:

  :0hc
   HEAD=`$FORMAIL -X "" |sed -e 's/</\&lt;/g'`
 
The log shows sed is working as expected, but $HEAD is empty.
So, I tried following recipe. 

  :0hc
   HEAD=|$FORMAIL -X "" |sed -e 's/</\&lt;/g'
   $HEAD

It seems to be working, but I don't feel comfortable:-<
Please tell me the right way.
Or is it a right way?
TIA
_/_/_/      Mitsuru FURUKAWA      _/_/_/
_/_/_/        Tokyo, Japan        _/_/_/
_/_/_/     mailto:furu(_at_)009(_dot_)com    _/_/_/
_/_/_/  http://www.009.com/furu/  _/_/_/