Parsing a soap response and displays a web url

Question

I am trying to parse the SOAP response of this XML:

$xml_body = '<?xml version="1.0" encoding="utf-8"?>
              <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" 
              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
                 <soap:Body>
                    <Interop_PushResponse xmlns="http://sample.org/webservices/">
                      <Interop_PushResult>&lt;?xml version="1.0" encoding="UTF-8"?&gt;&lt;Response Code="200"&gt;&lt;Description&gt;Update completed successfully&lt;/Description&gt;&lt;URL&gt;/Patient/PatientView.aspx?pid=96&lt;/URL&gt;&lt;/Response&gt;
                      </Interop_PushResult>
                    </Interop_PushResponse>
                  </soap:Body>
              </soap:Envelope>';

What I am trying to do is to get the <URL> tag value /Patient/PatientView.aspx?pid=96 and add it to a certain web URL, then display the complete URL address upon successful SOAP request and response cycle. I've tried doing what is instructed here in How to parse SOAP XML? but it doesnt work on me it shows no response. I am badly need help. TIA.