This study will assess the usefulness of a technique called complementary deoxyribonucleic acid (cDNA) microarray-an examination of a wide array of genes to identify disease-associated patterns-for measuring tumor response to chemotherapy in breast cancer patients. The study will look for "markers" that can help select the most effective type of chemotherapy. It will also evaluate the safety and effectiveness of a new drug combination of capecitabine and docetaxel.