A blood test every four months could help women at high-risk of ovarian cancer find tumours early, found a UK study.
There is currently no screening programme for the disease, so high-risk women are advised to have their ovaries and fallopian tubes removed.
In the trial on 4,348 women, cancers were detected earlier, when they should be easier to treat. However, it is not yet clear if the regular blood test would save lives.
Without screening, the only other option would be to keep an eye out for symptoms including: feeling constantly bloated; a swollen stomach; discomfort in the stomach or pelvic area; feeling full quickly when eating, or loss of appetite; and needing to urinate more often or more urgently than normal.
About two in every 100 women will develop ovarian cancer at some point in their life. But the study focused on women who faced a greater than one-in-10 chance. The trial, at 42 centres across the UK, monitored levels of a chemical called CA125 in women’s blood. Three times a year, doctors tracked changes in the levels of CA125, which is produced by ovarian tissue, to see if levels became elevated – a sign of cancer. The women also had annual scans, and surgery if doctors thought cancer was likely.
During three years of screening and the year after the last test, 19 cancers were detected. Ten of them were at an early stage. In the five years after that, 18 more ovarian cancers were detected. But now only one of them was at an early stage. The key principle of all cancer treatment is the earlier the tumour is found, the better the chances are of survival.
And screening was finding them earlier. However, a BBC News report says, the study has not been running for long enough to know if the screening saves lives.
While screening does detect cancer, tumours are far less likely to develop in the first place if women have surgery. Professor Usha Menon, one of the researchers and a professor of gynaecological cancer from University College London, said: “What we’re trying to do is get women to have surgery. But she said: “From my point of view, women really struggle with this issue of menopause, and it seems like four-monthly screening is better than symptom awareness.
“The screening definitely picks up less advanced disease, but we cannot say for sure if we’re saving lives.”
The report says previous trials have produced insufficient evidence for mass screening of all women. And in the US, the Food and Drug Administration recently recommended “against using currently offered tests to screen for ovarian cancer”, including ones looking at CA125.
One potential issue is having a blood test could put women off surgery. “This is what everyone’s worried about,” says Menon. However, she pointed out there was already an issue with women delaying surgery. She wants UK health officials to review screening and all other advice to high-risk women, the report says.
Athena Lamnisos, the CEO of The Eve Appeal, which part-funded the trial, said: “This research gives women hope and confidence that there is an evidence-based approach to screening if they decide to delay risk-reducing surgery.”
Annwen Jones, the CEO of Target Ovarian Cancer, said: “An effective screening programme for women at high risk of ovarian cancer due to family history would potentially have a major impact on mortality and survival from this disease.
“(But) it is still uncertain whether detecting ovarian cancer by screening increases the chance of a woman surviving the disease overall. Women at a higher risk of ovarian cancer still need to weigh up the risks and benefits of surveillance versus preventative surgery.”
Purpose: To establish the performance of screening with serum cancer antigen 125 (CA-125), interpreted using the risk of ovarian cancer algorithm (ROCA), and transvaginal sonography (TVS) for women at high risk of ovarian cancer (OC) or fallopian tube cancer (FTC).
Patients and Methods: Women whose estimated lifetime risk of OC/FTC was ≥ 10% were recruited at 42 centers in the United Kingdom and underwent ROCA screening every 4 months. TVS occurred annually if ROCA results were normal or within 2 months of an abnormal ROCA result. Risk-reducing salpingo-oophorectomy (RRSO) was encouraged throughout the study. Participants were observed via cancer registries, questionnaires, and notification by centers. Performance was calculated after censoring 365 days after prior screen, with modeling of occult cancers detected at RRSO.
Results: Between June 14, 2007, and May 15, 2012, 4,348 women underwent 13,728 women-years of screening. The median follow-up time was 4.8 years. Nineteen patients were diagnosed with invasive OC/FTC within 1 year of prior screening (13 diagnoses were screen-detected and six were occult at RRSO). No symptomatic interval cancers occurred. Ten (52.6%) of the total 19 diagnoses were stage I to II OC/FTC (CI, 28.9% to 75.6%). Of the 13 screen-detected cancers, five (38.5%) were stage I to II (CI, 13.9% to 68.4%). Of the six occult cancers, five (83.3%) were stage I to II (CI, 35.9% to 99.6%). Modeled sensitivity, positive predictive value, and negative predictive value for OC/FTC detection within 1 year were 94.7% (CI, 74.0% to 99.9%), 10.8% (6.5% to 16.5%), and 100% (CI, 100% to 100%), respectively. Seven (36.8%) of the 19 cancers diagnosed < 1 year after prior screen were stage IIIb to IV (CI, 16.3% to 61.6%) compared with 17 (94.4%) of 18 cancers diagnosed > 1 year after screening ended (CI, 72.7% to 99.9%; P < .001). Eighteen (94.8%) of 19 cancers diagnosed < 1 year after prior screen had zero residual disease (with lower surgical complexity, P = .16) (CI, 74.0% to 99.9%) compared with 13 (72.2%) of 18 cancers subsequently diagnosed (CI, 46.5% to 90.3%; P = .09).
Conclusion: ROCA-based screening is an option for women at high risk of OC/FTC who defer or decline RRSO, given its high sensitivity and significant stage shift. However, it remains unknown whether this strategy would improve survival in screened high-risk women.
Adam N Rosenthal, Lindsay SM Fraser, Susan Philpott, Ranjit Manchanda, Matthew Burnell, Philip Badman, Richard Hadwin, Ivana Rizzuto, Elizabeth Benjamin, Naveena Singh, D Gareth Evans, Diana M Eccles, Andy Ryan, Robert Liston, Anne Dawnay, Jeremy Ford, Richard Gunu, James Mackay, Steven J Skates, Usha Menon, Ian J Jacobs