MARLBOROUGH, Mass.--(BUSINESS WIRE)--EXACT Sciences Corporation (NASDAQ: EXAS) today reported that as of January 1, 2009, twelve states and the District of Columbia have legislative mandates requiring that available colorectal cancer (CRC) screening options offered by certain categories of insurers in these states must include all tests identified in the current American Cancer Society (ACS) screening guidelines, which include stool-based DNA (sDNA) screening.