The heads of Roche's ($RHHBY) diagnostics arm aren't worried about CMS reimbursement reductions, saying they are being offset by higher testing volumes. Most Big Pharma companies view diagnostics through the realm of companion diagnostics, but Roche has made the business one of its core competencies. (Just in case, don't expect the division to be sold off as part of the industry's continuing trend toward the streamlining of companies' business units.) Story