Non-Invasive Scan Shows Promise for Endometriosis Diagnosis in Oxford Trial

A non-invasive scan for endometriosis has shown promising results in a trial, boosting hopes for far quicker diagnosis. The trial, which included 19 women with the condition, suggests that an experimental radiotracer, called maraciclatide, can "light up" endometriosis on a scan. The current need for a surgical investigation is seen as a major obstacle to timely diagnosis, with women in England typically waiting nearly a decade.

Prof Krina Zondervan, head of department at the Nuffield Department of Women's and Reproductive Health (NDWRH) at the University of Oxford, and co-lead on the study, said: "The most prevalent subtype of endometriosis currently evades reliable detection, leaving women no choice for diagnosis other than invasive surgery. If these results are confirmed in larger phase 3 studies, imaging with maraciclatide could transform clinical research and practice and potentially empower the development of treatments for women across the globe."

Endometriosis is a condition where tissue found in the womb lining grows elsewhere, such as the ovaries and fallopian tubes. Symptoms include painful periods, painful bowel movements, pain when urinating and pain during or after sex. It is thought to affect about one in 10 women and can affect fertility. There are treatments, including hormone medication and surgery, but the lengthy delays to diagnosis have been a continuing problem.

Research by the charity Endometriosis UK suggests women in England currently wait an average of 9 years 4 months – rising to 11 years for women from ethnic minority communities. Wes Streeting, the health secretary, highlighted the problem in the government's renewed Women's Health Strategy, earlier this month.

Endometriosis can progress, leading to more severe physical symptoms and restricting the ability to make informed choices around fertility. Peritoneal endometriosis, the earliest and most common form of the condition, cannot be reliably detected with existing imaging techniques. Standard MRI scans are typically only able to pick up structural changes that appear with more advanced disease.

The latest trial investigated the use of a radiotracer, called maraciclatide, developed by the UK-based company Serac. The tracer is designed to bind to tissue that is in the process of creating new blood vessels – a cardinal feature of endometriosis. Nineteen patients, all due to undergo laproscopies for endometriosis, were given an infusion of the tracer and then underwent a scan called a Spect-CT. The scan results aligned with the surgical diagnosis in 16 out of 19 cases and there were no false positives.

Serac said it plans to validate the findings in larger phase 3 trials. If confirmed as effective, a minimally invasive scan could make it easier to run trials for new treatments.

Dr Tatjana Gibbons, lead author on the paper and also of the NDWRH, said: "These exciting findings indicate that maraciclatide offers a highly promising diagnostic and monitoring tool, particularly for superficial peritoneal endometriosis, which is the most common and yet the hardest type of endometriosis to identify."

The findings are published in The Lancet Obstetrics, Gynaecology, & Women's Health.