Cancer chemoprevention involves the chronic administration of a synthetic, natural or biological agent to reduce or delay the occurrence of malignant tumour. The potential value of this approach has been demonstrated with trials in breast, prostate and colon cancer. The paradigm for developing new chemo preventive agents has changed markedly in the last decade and now involves extensive preclinical mechanistic evaluation of agents before clinical trials are instituted and a focus on defining biomarkers of activity that can be used as early predictors of efficacy.In this review, overall survival rate (OSR) result and safety data were evaluated based on data from four clinical trials on combined therapies of Docetaxel and Tamoxifen among breast cancer patients, which were published in peer-reviewed journals. Data was extracted from single treatment trials of Docetaxel plus Cisplatin, and Tamoxifen plus Vorinostat, and randomized trials of Docetaxel plus Capecitabine, and Tamoxifen plus Buserelin. Docetaxel was found to have slightly longer OSR than Tamoxifen in combined therapies, and it has better individual strength in combined therapies based on OSR comparison in the trials’ treatment arms. However, a considerable number of toxicities caused by combined therapies of both drugs negates the superiority of the efficacy of combined therapies of one of the drugs over the other. Although other combined cancer drugs boost efficacy of Docetaxel and Tamoxifen in the combined therapies, they should be selected to minimize the toxicities in combined therapies of both drugs.