Remarkable differences in COX-2 estimation exist between our studies and that by Fujita et al. Firstly, whilst we assessed only COX-2 and its effect on tumour size, Fujita et al used COX-2 index which was defined as the ratio of COX-2 to COX-1 (COX-2/COX-1) in the colorectal carcinomas. Here, PTGS2 is linked to colorectal carcinoma.