question: Elaborate on the potential efficacy of gemcitabine for the treatment of recurrent, platinum-resistant epithelial ovarian cancer.
answer: Gemcitabine is a novel agent that has shown consistent activity as a single agent in the treatment of platinum-resistant ovarian cancer and a favorable toxicity profile. Because of its clinical and preclinical synergism with platinum analogs, gemcitabine has been combined with carboplatin as a convincing approach in the treatment of platinum-sensitive recurrent ovarian cancer patients. Gemcitabine and prolonged oral etoposide have shown reproducible single-agent activity in patients with platinum/paclitaxel-resistant ovarian cancer. The combination of carboplatin and gemcitabine resulted in significantly higher response rates and improved progression-free survival when compared with carboplatin alone. A biweekly schedule of gemcitabine combined with PLD is an active and safe chemotherapy regimen with acceptable and easily manageable toxicities in women with recurrent platinum-resistant ovarian cancer.  Pertuzumab may add activity to gemcitabine for the treatment of platinum-resistant ovarian cancer.  The regimen of gemcitabine combined with ifosfamide and anthracycline is feasible, tolerable and effective in patients with recurrent platinum resistant/refractory epithelial ovarian cancer. Gemcitabine plus endostar significantly improved the prognosis in patients with platinum-resistant recurrent ovarian cancer, especially in those with malignant effusion. Though the endostar cohort also improved median OS by 2.1 months, there was no statistically significant difference compared with gemcitabine alone cohort in this case.