LGR5 and cancer: Since there is no definitive determinant of cancer stem cells, we evaluated the expression of four putative stem cell markers, namely, CD133, CD44 variant 6 (CD44v6), aldehyde dehydrogenase-1 (ALDH1) and leucine-rich repeating G-protein-coupled receptor-5 (LGR5) and investigated whether they were effective clinical biomarkers to identify patients with a high risk of post-operative peritoneal metastasis.