Use of an ovarian cancer risk algorithm that incorporated serum CA-125 screening was able to double the number of invasive epithelial ovarian cancers detected.
The use of an ovarian cancer risk algorithm that incorporated serum cancer antigen 125 (CA-125) screening was able to double the number of invasive epithelial ovarian or tubal cancers detected, according to the results of a study of the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) published in the Journal of Clinical Oncology.
“There is currently no national screening program for ovarian cancer, as research to date has been unable to provide enough evidence that any one method would improve early detection of tumors,” said Usha Menon, MD, UKCTOCS coprincipal investigator and trial coordinator at University College London, in a prepared statement. “These results are therefore very encouraging. They show that use of an early detection strategy based on an individual’s CA-125 profile significantly improved cancer detection compared to what we’ve seen in previous screening trials.”
The trial investigated a new multimodal strategy for screening for ovarian cancer. The study screened 46,237 women aged 50 or older by interpreting annual CA-125 in the context of a risk of ovarian cancer algorithm (ROCA). This algorithm used a statistical calculation to interpret changing levels in CA-125, which gives a more accurate prediction of a woman’s individual risk of developing cancer, compared to the conventional screening method which uses a fixed cut-off point for CA-125.
Based on this algorithm, women in the trial were categorized as normal risk (return to annual screening), intermediate risk (repeat CA-125), or elevated risk (repeat CA-125 and transvaginal ultrasound).
In about 300,000 women-years of annual incidence screening, 640 women underwent surgery and 133 had primary invasive cancer. The researchers found 22 invasive cancers in 1 year of screening, of which one was detected by the ROCA.
“Excess surgical morbidity in patients with false positive diagnoses is a key concern, especially with increasing comorbidity in the older women,” the researchers wrote. “In our study, the rate of complications in women with benign or normal histology, most of whom underwent laparoscopic bilateral salpingo-oophorectomy, was 4.5%.”
The multimodal screening strategy had a sensitivity of 85.8% and a specificity of 99.8%. ROCA detected 87.1% of the invasive epithelial ovarian or tubal cancers. In contrast, using the fixed CA-125 cut-offs would have detected between 41.3% and 66.5% of cancers.
“Our data provide prospective evidence of the improvement that CA-125 velocity analysis brings to invasive epithelial ovarian or tubal cancers detection compared with a predetermined cutoff,” the researchers wrote. “The impact of such screening on ovarian cancer mortality will be known later in 2015 when follow-up is complete. However, 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.”