PTGS2 and rectal cancer: Copy number increase of EFNA1 (1q22), PTGS2 (1q31.1), KDM5B (1q32.1), ESRRG (1q41), KIFC1 (6p21.32), PBX2 (6p21.32) and SOX4 (6p22.3) were only detected in rectal cancer in array CGH.