Annual ovarian cancer screening can detect tumors earlier but doesn’t save lives, suggests one of the largest studies ever in the general population.
While the discovery is a blow to those affected by ovarian cancer, it is hoped that earlier diagnosis could reduce the amount and intensity of treatment women undergo.
Around 7,500 British women are diagnosed with ovarian cancer each year and 4,000 die from it, making it the deadliest gynecological cancer. The absence of a single tell-tale symptom means that the disease is often only diagnosed at an advanced stage – and early diagnosis is crucial because although 80-90% of women whose cancer is caught early survive for at least five years, this figure decreases to 25% when the disease is detected late.
The hope was that screening for signs of ovarian cancer in healthy women might improve these survival rates, as did screening for cervical cancer in the population.
The study, conducted by researchers at University College London, analyzed data from more than 200,000 postmenopausal women recruited for the trial between 2001 and 2005. Half of the women were not screened, while the others have been offered an annual vaginal ultrasound or annual blood test to detect a cancer-related protein called CA125, followed by an ultrasound for those whose levels of that protein are altered.
The results, published in the medical journal The Lancet, found that although blood test screening detected 39% more cancers at an early stage (stage I / II), compared to vaginal ultrasound and no screening groups, this did not translate into not by a reduction in deaths from disease.
“Either we have to find more early stage disease individuals and fewer late stage disease individuals through screening, and / or this disease is such that even if you did, the biology of [ovarian cancer] This means it will be aggressive no matter what you do, even if you find it at an early stage, ”said Prof Mahesh Parmar, director of the Medical Research Council’s Clinical Trials Unit at UCL and lead author of the article.
The researchers noted that women identified by the blood test did not respond as well to standard treatment as women who had not been screened but whose cancers were identified early based on their symptoms.
As disappointing as the results are, Parmar pointed out that in women with symptoms of ovarian cancer, early diagnosis, combined with significant improvements in the treatment of advanced disease over the past 10 years, could still save many lives.
“Our trial showed that screening was not effective in women who had no symptoms of ovarian cancer; in women with symptoms, early diagnosis, combined with this better treatment, can still make a difference in quality of life and potentially improve outcomes, ”he said. “Also, getting a diagnosis quickly, regardless of the stage of the cancer, is extremely important for women and their families.”
The team is conducting further analysis to determine whether early detection may lead to less extensive surgery or chemotherapy.
Athena Lamnisos, Executive Director of Appel Eve, which funds research into cancer of the uterus, ovary, cervix, vulva and vagina, said: “It is disappointing that this research program has not shown a reduction in ovarian cancer mortality and therefore cannot be recommended as a national screening program. However, its impact on early diagnosis is impressive and significant.
“Early diagnosis will often reduce the amount and intensity of treatment, which makes all the difference for women and their families living with cancer. It may also have given them more precious time with their loved ones. “
Other screening methods are also in development, but it could take years to see if they would save more lives. For now, the focus should be on improving awareness of the most common symptoms and ensuring that women who suffer from them are promptly referred to an oncologist, said Usha Menon, professor of gynecological cancer at the ‘UCL, who led the study.
“The symptoms of ovarian cancer can be quite vague and similar to symptoms caused by less serious conditions, which can make detection of the disease tricky,” said Michelle Mitchell, managing director of Cancer Research UK. “Whether it’s going to the bathroom more often, pain, bloating or whatever, talk to your GP – in most cases it won’t be cancer, but it’s best to have it checked. “