Endometrial carcinoma: a review of chemotherapy, drug resistance, and the search for new agents.

Adenocarcinoma of the endometrium represents the most common gynecologic malignancy in developed countries. Although early-stage cancers are effectively treated surgically, commonly without adjuvant therapy, the treatment of high-risk and advanced disease is more complex. Chemotherapy has evolved into an important modality in high-risk early-stage and advanced-stage disease, and in recurrent endometrial cancer. Taxane-based therapy consistently demonstrates the highest response rates in the first-line and salvage settings of endometrial cancer. Unfortunately, response to chemotherapy is modest and strategies are needed to predict chemotherapy-responsive and chemotherapy-resistant populations. Chemotherapy resistance mediated by overexpression of drug efflux pump proteins and mutations in β-tubulin isoforms in both primary and recurrent disease represent unique treatment challenges and highlight the need for new agents that are less susceptible to these known resistance pathways. Epothilone B analogs are novel cytotoxic agents with activity in solid tumors, including advanced/recurrent endometrial carcinoma, and may have unique properties that can overcome resistance in some settings. These agents alone and in combination represent a new therapeutic opportunity in endometrial carcinoma.