Parsing in PHP. How to replace a string?

When parsing, we display some information

echo .$item->description.'<br><br>';

But in this info you need to add a reflink. To do this, you can use the str_replace()function, and for this, everything that is displayed must be placed in a variable and there, through the function, replace strings.
But this combination doesn’t work.

   $refer = echo .$item->description.'<br><br>'; 
    $refer = str_replace('<A href="http://instaforex.com/ru">instaforex.com</A>',
            '<A href="http://instaforex.com/ru" target="_blank">instaforex.com</A>', $refer); 
echo $refer;

What’s wrong?
Thank you.


Answer 1, authority 100%

$refer = str_replace(
  '<A href="http://instaforex.com/ru">instaforex.com</A>',
  '<A href="http://instaforex.com/ru" target="_blank">instaforex.com</A>',
  $item->description.'<br><br>'); 
echo $refer;

And get out of the 1995-style)) I’m talking about tags in capital letters (<A ...) and unclosed <br>(<br />);