Sunday 8 May was World Ovarian Cancer Day, raising awareness of the seventh most common cancer in women. Ovarian cancer has the worst prognosis and highest mortality rate of all gynaecological cancers;1 and has historically been known as the ‘silent killer’2 because early-stage symptoms are commonly overlooked, ignored or mistaken for something less malign.3
Risk factors for ovarian cancer
The risk factors for ovarian cancer are well established and include:
- Advanced age: the risk rises sharply from the age of 45 and is highest between 75 and 791
- History of breast cancer, particularly ER negative or breast cancer which has occurred at a younger age1
- Between 5% and 15% of cases are triggered by an inherited genetic mutation1
- HRT use1
- Asbestos exposure1
- Obesity or diabetes1
- A woman’s risk of ovarian cancer increases with the number of ovulatory cycles she goes through – this can be offset by taking the contraceptive pill, pregnancy and breastfeeding, or sterilisation4
Lack of awareness and its effects
The earlier ovarian cancer is detected, the greater the patient’s chance of survival: 98% of women diagnosed with Stage 1 ovarian cancer will survive for at least one year, compared to only 54% of women diagnosed at Stage 4.5 However, only around 20% of ovarian cancer diagnoses occur at an early stage, in part because there are no reliable screening tests available for women who are not yet experiencing symptoms.6 A 20-year study of more than 200 000 women, which culminated in 2021, found that annual ultrasound and blood test screenings for ovarian cancer have no benefit in reducing mortality.7 This is in stark contrast to, for example, breast and cervical cancers, where mammograms and smear tests are proven methods of early screening.
Unfortunately, even once the cancer has progressed and symptoms do begin to manifest, patients may not be aware that they are at risk – only one in five women recognise bloating as a symptom of ovarian cancer; while just one in 100 know that increased need to urinate is a symptom.8
Screening, prevention and treatment
There is clearly a pronounced need for wider awareness of the preliminary symptoms of ovarian cancer, as well as for further investigation of potential screening options. Early-stage research has indicated that cells collected during cervical smears can contain the epigenetic signature of ovarian and breast cancers, acting as an early warning for patients and healthcare providers.9 Elsewhere, a new trial is investigating the preventive potential of removing the fallopian tubes of women who are particularly at risk, followed by the ovaries at a later stage, to reduce the threat of ovarian cancer, preserve the ovaries and avert the symptoms of early menopause.10
While the options for ovarian cancer screening and prevention remain limited, the last few years have seen significant innovation in treatment and drug development. A 2022 study found that treatment with ixabepilone plus the monoclonal antibody bevacizumab, as opposed to the standard of ixabepilone alone, delivers positive results in increasing survival rates and halting the progression of advanced or treatment-resistant ovarian cancer.11
In February 2022, niraparib was approved by the National Institute of Health and Care Excellence for treatment of recurrent ovarian cancer in England and Wales.12 It became the first ovarian cancer treatment to shift from the ‘managed access’ Cancer Drugs Fund,13 which allows patients to access novel treatments for a fixed period of time, to NHS-funded routine commissioning, meaning it can now be offered over an unlimited time period. In the US, meanwhile, the Food and Drug Administration has placed treatment combining the novel cytokine nemvaleukin alfa with pembrolizumab on its ‘fast track’ for expedited review, after phase 1 and 2 trials showed significant benefits for patients with platinum-resistant ovarian cancer.14
- Momenimovahed Z, Tiznobaik A, Taheri S, Salehiniya H. Ovarian cancer in the world: epidemiology and risk factors. Int J Womens Health 2019;11:287-299. https://doi.org/10.2147/IJWH.S197604
- Jasen P. From the “silent killer” to the “whispering disease”: ovarian cancer and the uses of metaphor. Med Hist 2009;53(4):489-512. https://doi.org/10.1017/s0025727300000521
- Goff B. Ovarian cancer is not a silent killer – recognizing its symptoms could help reduce misdiagnosis and late detection. The Conversation Available at: https://bit.ly/3N2YUzg [Accessed May 2022].
- Target Ovarian Cancer. Protective factors: reducing the risk of ovarian cancer. 2020. Available at: https://bit.ly/3P4yE9N [Accessed May 2022].
- Cancer Research UK. Ovarian cancer survival by stage at diagnosis. 2019. Available at: https://bit.ly/3M0286y [Accessed May 2022].
- American Cancer Society. Can ovarian cancer be found early? 2020. Available at: https://bit.ly/3KYe5s4 [Accessed May 2022].
- Menon U, Gentry-Maharaj A, Burnell M, Singh N, Ryan A et al. Ovarian cancer population screening and mortality after long-term follow-up in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial. Lancet 2022;397(10290):2182-2193. https://doi.org/10.1016/S0140-6736(21)00731-5
- Target Ovarian Cancer. Ovarian Cancer Awareness Month. 2022. Available at: https://bit.ly/3P5bWyj [Accessed May 2022].
- Barrett JE, Herzog C, Jones A et al. The WID-BC-index identifies women with primary poor prognostic breast cancer based on DNA methylation in cervical samples. Nat Commun 2022;13(449). https://doi.org/10.1038/s41467-021-27918-w
- PROTECTOR study team. Preventing ovarian Cancer through early excision of tubes and late ovarian removal (PROTECTOR) study. 2021. Available at: https://bit.ly/38gsGBV [Accessed May 2022].
- Roque DM, Siegel ER, Buza N et al. Randomised phase II trial of weekly ixabepilone ± biweekly bevacizumab for platinum-resistant or refractory ovarian/fallopian tube/primary peritoneal cancer. Br J Cancer 2022:1-9. https://doi.org/10.1038/s41416-022-01717-6
- Target Ovarian Cancer. Future is certain for niraparib in recurrent ovarian cancer. 2022. Available at: https://bit.ly/3KV5y9t [Accessed May 2022].
- Cancer Drugs Fund. 2022. Available at: https://bit.ly/3MXgMvC [Accessed May 2022].
- Virgil H. Nemvaleukin alfa plus pembrolizumab demonstrates promising responses, disease control in platinum-resistant ovarian cancer. 2022. Available at: https://bit.ly/3vSQZiu [Accessed May 2022].