$re = '/<a .*?href=([\'"]?).*?\/?download.aspx\?myid=\{?([0-9a-f]{8}-?[0-9a-f]{4}-?[0-9a-f]{4}-?[0-9a-f]{4}-?[0-9a-f]{12})\}?\1.*?>(.*?)<\/a>/mi';
$str = '<a clicktracking=off href="https://www.test.com/1.pdf">test</a><br />Test<br />Test</div><br><div> </div><br><div><a clicktracking=off href="download.aspx?myID=11111111-2222-3333-4444-555555555555">Teet.docx</a></div>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php