While our observation of PR in 1 out of 16 (6.3%) patients with CRC is lower than the data from these earlier studies, the discrepancy may be attributable to the fact that earlier studies selected for MGMT deficient patients who are expected to respond favorably to single-agent TMZ while our study enrolled patients irrespective of MGMT status; therefore, it would be premature to rule out possible benefit from this combination in CRC. This evidence concerns the gene MGMT and colorectal carcinoma.