Among wild-type KRAS patients , those with LC had significantly improved PFS when treated with cetuximab compared to BSC ( median @ versus @ months , HR @ -LSB- @-@ @ -RSB- , p < @ ) , whereas those with RC did not ( median @ versus @ months , HR @ -LSB- @-@ @ -RSB- , p = @ ) , -LSB- interaction p = @ -RSB- .