Cancer marker sets consisting of particular genes differentially expressed in tumours provide improved accuracy of predicting effectiveness of paclitaxel or paclitaxel-like drug treatment against a cancer. These sets are further useful for screening drug candidates for paclitaxel-like cancer treatment activity. The cancer marker sets may be used in a clinical setting to provide information about the likelihood that a cancer patient would or would not respond to paclitaxel or paclitaxel-like drug treatment.