UK Study Suggests Potential Mortality Benefit of Ovarian Cancer Screening in Postmenopausal Women

Key Points

  • Screening was associated with nonsignificant reductions in ovarian cancer mortality in postmenopausal women.
  • There was some evidence of mortality reduction in screening groups during years 7 to 14 of follow-up.

As reported in The Lancet by Jacobs et al, the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) suggests there may be a mortality benefit of ovarian cancer screening in postmenopausal women.

Study Details

In the trial, 202,546 postmenopausal women aged 50 to 74 years from 13 centers in England, Wales, and Northern Ireland who were eligible for analysis were randomly assigned 1:1:2 between June 2001 and October 2005 to annual multimodal screening with serum CA-125 interpreted with use of the risk of ovarian cancer algorithm (n = 50,624), annual transvaginal ultrasound screening (n = 50,623), or no screening (n = 101,299).

The primary outcome was death due to ovarian cancer by December 31, 2014. Women with previous bilateral oophorectomy or ovarian malignancy, increased risk of familial ovarian cancer, or active nonovarian malignancy were excluded from the study.

Mortality Rates

Screening ended on December 31, 2011, and included 345,570 multimodal screening and 327,775 ultrasound screening annual screening episodes. At a median follow-up of 11.1 years, ovarian cancer was diagnosed in 1,282 (0.6%) women, including 338 (0.7%) in the multimodal-screening group, 314 (0.6%) in the ultrasound-screening group, and 630 (0.6%) in the no-screening group. Death from ovarian cancer occurred in 148 (0.29%) of the women in the multimodal-screening group, 154 (0.30%) in the ultrasound-screening group, and 347 (0.34%) in the no-screening group.

Compared with the no-screening group over years 0 to 14, there were nonsignificant reductions in ovarian cancer mortality of 15% (95% confidence interval [CI=  –3% to 30%, P = .10) in the multimodal-screening group and 11% (95% CI = –7% to 27%, P = .21) in the ultrasound-screening group. The mortality effect consisted of a reduction of 8% (95% CI = –20% to 31%) in years 0 to 7 and 23% (95% CI = 1%–46%) in years 7 to 14 in the multimodal-screening group and 2% (95% CI = –27% to 26%) in years 0 to 7 and 21% (95% CI = –2% to 42%) in years 7 to 14 in the ultrasound-screening group.

In a prespecified analysis excluding prevalent cases of ovarian cancer, multimodal screening was associated with a significant reduction in ovarian cancer mortality (P = .021) vs no screening, with an overall average mortality reduction of 20% (95% CI = –2% to 40%) and reductions of 8% (95% CI = –27% to 43%) in years 0 to 7 and 28% (95% CI = –3% to 49%) in years 7 to 14.

The investigators concluded: “Although the mortality reduction was not significant in the primary analysis, we noted a significant mortality reduction with multimodal screening when prevalent cases were excluded. We noted encouraging evidence of a mortality reduction in years 7 to 14, but further follow-up is needed before firm conclusions can be reached on the efficacy and cost-effectiveness of ovarian cancer screening.”

The study was funded by the Medical Research Council, Cancer Research UK, Department of Health, and The Eve Appeal.

Ian J. Jacobs, FRCOG, of the University of New South Wales, Sydney, Australia, and Usha Menon, FRCOG, of the University College London, United Kingdom, are the corresponding authors of The Lancet article.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.