The investigators have developed an endoscopic approach (EndoVe system) for delivering the electric pulses to internal cancers and are currently seeking to evaluate its efficacy in the treatment of inoperable colorectal cancer. The treatment procedure is similar to standard endoscopic colorectal examination (colonoscopy) with the added element of an intravenous injection of bleomycin followed after eight minutes by the delivery of electric pulses (each one less than 1msec in duration). The pulses are endoscopically delivered directly to the tumour mass. The entire procedure is minimally invasive and does not require intensive care follow up or stitches. If the treatment is successful the tumour will shrink in size in the weeks following the procedure.