Cancer Stem Cells (Csc's): Emerging Concept and Stratgey for Targeting Progression of Epithelial Ovarian Cancer

The estimated new cases of ovarian cancer in the United States of America (USA) in 2014 is 21, 980, and the estimated deaths is 14,270. It ranks 5th overall for cancer death in women, counting for 5% of all cancer deaths in women (lung, breast, colorectal, pancreatic are 1-4 respectively). At time of diagnosis, 15% of the total cases are localized, 18% are regional, and 61% are distant. In 2011, there were an estimated 188,867 women living with ovary cancer in the United States. The Standard treatment of ovarian cancer consists of surgical resection of disease followed by taxane and platinum-based chemotherapy which yields a partial response rate of about 80% and a complete response rate of 40%-60% in patients with advanced disease. However, the recurrence rate is approximately 70% and five-year survival is 45% in patients with advanced disease. It appears that the majority of ovarian cancer cells are initially chemosensitive as evidenced by the initial response rates. However, the high recurrence rates suggest development of chemoresistance. It is thought that some cells are not killed by chemotherapy, or they repopulate after exposure to chemotherapeutic agents. These cells have been described as ovarian cancer stem cells (CSCs).