PHP::Include has some basic functionality. There are also a raft of PHP:: modules. However given that you have a functional PHP script running on a web server and want to get at the data from your Perl CGI code you are possibly stuck with something ugly (and slow) like:

use LWP::Simple;
my $php_html = get( http://somesite.com/blech.php );
print "Content-Type: text/html

<h1>PHP is yucky</h1>
$php_html
<h1>Brought to you with the power of Perl</h1>";
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