In the multimodal screening (MMS) arm of the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS), women underwent serial serum CA-125 testing.8,9 CA-125 velocity was interpreted by using a risk of ovarian cancer algorithm (ROCA), which compares an individual's serial profile with that of cases and controls to estimate the risk of having ovarian cancer.10 We report here on the impact of using CA-125 velocity compared with a single-threshold rule on ovarian cancer detection during 296,911 woman-years of annual incidence screening. Here, MUC16 is linked to ovarian carcinoma.