Development of grade 2 + rash on cetuximab was associated with a trend towards increased OS ( HR 0.61 with 95 % CI 0.36-1 .02 and p = 0.06 ) and PFS ( HR 0.68 with 95 % CI 0.45-1 .03 and p = 0.07 ) as compared to grade 0/1 rash in patients with WT tumours .