Test Offers Hope for Catching Ovarian Cancer Earlier
The risk of ovarian cancer algorithm (ROCA), based upon serial measurements of cancer antigen 125 (CA-125), can double the number of screen-detected ovarian cancers, compared with a single measurement of the marker. The test, developed by Abcodia (United Kingdom) is set to be released both in the United States and the United Kingdom later this […]
The risk of ovarian cancer algorithm (ROCA), based upon serial measurements of cancer antigen 125 (CA-125), can double the number of screen-detected ovarian cancers, compared with a single measurement of the marker. The test, developed by Abcodia (United Kingdom) is set to be released both in the United States and the United Kingdom later this year. “The test represents a unique opportunity to address a significant clinical unmet need for any post-menopausal woman or pre-menopausal women with a clear family history of ovarian cancer,” said Julie Barnes, Ph.D., cofounder and CEO of Abcodia, in a statement. Recent clinical trial results “highlight the sophistication of ROCA in being able to accurately distinguish between asymptomatic women with and without ovarian cancer, despite in many cases, their serum CA125 level appearing within the normal range.” In mid-May, Abcodia announced raising an $8 million round of venture capital financing, which will allow it to launch the ROCA test in the United Kingdom this summer (following CE Mark) and in U.S. markets later in 2015 as a laboratory-developed test. In the United Kingdom, Abcodia says, the test will cost about $229. The ROCA test, the company says, is more effective than traditional, single measurements of CA125, which raise clinical suspicions based on a fixed cutoff (35 unit per mL). Abcodia says that longitudinal algorithms allow the personalization of disease detection by measuring biomarker levels in an individual over time. Detecting changes in an individual, rather than relying on populational averages for cutoff thresholds, can “substantially increase the power of a test” by reducing both false positives and negatives. Previous modeling studies using data from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial have suggested that up to a third of the ovarian cancer cases could have been detected earlier if CA-125 velocity (changes in the marker) had been used instead. According to a study published May 11 in the Journal of Clinical Oncology, screening for ovarian cancer with ROCA doubled the number of screen-detected invasive epithelial ovarian or tubal cancers (iEOCs) compared with a fixed CA125 cutoff. The large study analyzed data from 46,237 women (aged 50 years or older) participating in the United Kingdom Collaborative Trial of Ovarian Cancer Screening. These women had been randomized to undergo incidence screening using the multimodal strategy (MMS). Measurements of annual serum CA-125 levels were interpreted with ROCA and women’s predetermined screening and care was triaged based on their risk categorization. The researchers found that from June 25, 2002 to Dec. 21, 2011, 296,911 incidence screens were performed and 640 women underwent surgery. Of those, 133 had iEOCs. Overall, 22 interval iEOCs occurred within one year of screening, of which one was detected by ROCA but was managed conservatively after clinical assessment. The sensitivity and specificity of MMS for detection of iEOCs were 85.8 percent and 99.8 percent, respectively. ROCA alone detected 87.1 percent of the iEOCs while fixed CA-125 cutoffs at the last annual screen (>35, >30, and > 22 U/mL) would have identified 41.3 percent, 48.4 percent, and 66.5 percent of the cases, respectively. At the last relevant annual screen, median serum CA-125 in the 133 women with screen-detected iEOCs was 33.6 U/mL, with more than half (52.6 percent) of these women having CA-125 levels within the normal range (35 U/mL or less). All cancer-free women were ruled out, when ROCA was used in conjunction with an ultrasound. “Our current findings are of immediate importance because they highlight the need to examine serial change in biomarker levels in the context of screening and early detection of cancer,” write the authors, led by Usha Menon, M.D., from University College London (United Kingdom). “Reliance on predefined single-threshold rules may result in biomarkers of value being discarded.” Takeaway: ROCA, with its serial measurements of CA125, represents a significant opportunity to improve earlier detection of ovarian cancer.