The superconducting CeFe1-x Cox AsO (Co=0.1) oxyarsenide with a transition temperature (Tc) 11.4 K has been investigated by in situ high pressure synchrotron x-ray diffraction, magnetization, and resistivity measurements. The experiments performed at 10 K up to 6 GPa and at room temperature (RT) up to 55 GPa indicate large anisotropic lattice compression. A pressure induced structural change to a collapsed tetragonal structure is observed above 10 GPa at RT. We report here the enhancement of Tc from 11.4 to 12.3 K with a small increase in pressure up to 0.4 GPa and is first observed in an electron doped Ce-1111 system. © 2011 American Institute of Physics.