Yes, it is possible ... depending on what he/she did while out of the US. If he/she worked or went to school outside of the US ... had a foreign residence ... had a foreign bank account ... etc ..... continuous residence can, and should be challenged by CIS
Meet with an attorney, many use Skype, and have him/her review your entire life story.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.