Ovarian cancer (OC) is the seventh most common cancer for women worldwide in 2012(1). In Canada, 17,000 women are living with ovarian cancer, and it is ranked the fifth most common cancer for Canadian Canadian women in 2013(2). According to the recently released surveillance report, 2,700 new cases will be diagnosed in 2014 in Canada?(3). Moreover, it is the most fatal women’s cancer, with the average of 45% 5-year survival rate comparing to 89% of the survival rate for women with breast cancer(4). The 5 year survival rate is only 5% for those who were diagnosed with the most advanced stage disease compared to 75% of survival rate at early stage(5). However, most of the OC patients are diagnosed at the advanced stage, e.g. 51% of …show more content…
Particularly, PFS is considered as the primary outcome in evaluating the efficacy of a particular drug in maintenance therapy, which focuses on the estimation of recurrent rate. In the study, CT scan will be employed to detect the OC recurrence according to the standard operational process. Based on the Response Evaluation Criteria In Solid Tumors (RECIST) standard, the frequency of tumor re-evaluation is recommended as 6-8 weeks for a phase II clinical trial where the beneficial effect of therapy is not known, specifically when PFS is taken as the primary outcome(49). However, as the OC patients in our study may not stand the high frequency of CT scans as shown in previous study(40), 6 months interval CT scan will be applied in the study. Meanwhile with the optimized CT scan schedule to reduce the side effect, CA-125 blood test will be employed as an auxiliary. As per ovarian cancer, CA-125 test is another option for early screening of the OC recurrence and it is recommended by Gynecological Cancer Intergroup (GCIG) in clinical trial for the progression/recurrence of OC(50, 51). CA-125, as one of the serum tumor markers, is the most accurate tumor maker used for monitoring therapeutic response for recurrent OC(52, 53). The abnormal level of CA-125 (>35U/Ml) shows strong indication of the recurrence of OC, even with a progressive low-level increase in serum CA-125 level (54,